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Geneva Protocol | Chemical Weapons, Disarmament & Treaty | Britannica

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Geneva Protocol, (1924) League of Nations draft treaty to ensure collective security in Europe. Submitted by Edvard Beneš, the protocol proposed sanctions against an aggressor nation and provided a mechanism for the peaceful settlement of disputes. States would agree to submit all disputes to the

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Law enforcement officers in Ferguson, Mo., have used tear gas extensively in the wake of the police-shooting death of Michael Brown, an 18-year-old unarmed African-American. The conflict in Ferguson led one PolitiFact reader to ask us to check the accuracy of a social-media meme now circulating that addresses the legality of tear gas.

The meme - posted by the group OurTime.org, an advocacy group for young Americans - said, "Tear gas has been classified as a chemical weapon and banned in international conflict since 1993. Why is its use allowed by U.S. police forces?" The post had garnered 143,000 likes, 42,000 shares, and 35,000 comments by late August. We wanted to know if it was accurate.

First, some background on tear gas. It is a broad term for chemical compounds that temporarily make people unable to function by causing irritation to the eyes, mouth, throat, lungs, and skin, according to the Centers for Disease Control and Prevention. Pepper spray and CS gas are among the most commonly used.

The CDC says that "prolonged exposure, especially in an enclosed area, may lead to long-term effects such as eye problems including scarring, glaucoma, and cataracts, and may possibly cause breathing problems such as asthma." However, the agency adds that "if symptoms go away soon after a person is removed from exposure to riot control agents, long-term health effects are unlikely to occur."
Has tear gas been 'banned in international conflict since 1993'?
This is close to being accurate. The Chemical Weapons Convention bans the development, production, acquisition, stockpiling, retention, transfer or use of chemical weapons. And tear gas qualifies under the convention as a chemical weapon.

Specifically, Article I (5) of the convention says, "Each State Party undertakes not to use riot control agents as a method of warfare," while Article II (7) defines "riot control agent" as: "Any chemical not listed in a Schedule, which can produce rapidly in humans sensory irritation or disabling physical effects which disappear within a short time following termination of exposure."

The meme is incorrect, however, when it comes to the year the convention came into force. It was finalized in 1993 but took effect on April 29, 1997 - 180 days after the 65th country, Hungary, ratified the treaty, as the convention set forth. The United States is covered by this provision, the Senate having ratified the convention five days before it went into force.

In addition, there may be a gray area for use by the military. When President Gerald Ford signed an earlier, decades-old agreement covering chemical weapons, the Geneva Gas Protocol of 1925, the United States reserved the right to use tear gas in a limited number of contexts, such as for controlling a riot at a prisoner-of-war detention area - just not against troops engaged in battle. Anthony Clark Arend, a Georgetown University professor of government and foreign service, said he believes that this limited exception would also hold water under the Chemical Weapons Convention.
How relevant is that to police?
This part is more murky, because the same convention being touted by the meme's authors specifically states that law enforcement use within a country is permitted. "Law enforcement including domestic riot control purposes" is "not prohibited under this convention," says Article II (9) (d).

This bifurcation between a permitted domestic use and a banned international use is unusual in such accords, said Brian Finlay, managing director of the Stimson Center, a think tank that focuses on global security issues.

As for how it happened, there's a backstory.

According to the Organization for the Prohibition of Chemical Weapons, the international group that helps enforce the Chemical Weapons Convention, riot control agents were "the topic of long and heated debates" during negotiations of the convention. In the end, a compromise was reached, the group says, allowing the use of tear gas for riot control but prohibiting it for warfare.

Indiana University law professor David P. Fidler, who has studied the issue, said that while there's been some controversy over what this article of the convention permits in some contexts, "law enforcement use of tear gas has not been one of them."

When we contacted OurTime.org, co-founder Jarrett Moreno told us that "the focus of our post was raising an ethical and moral question: If we can't use tear gas on our enemies, why is it acceptable to use on our own citizens? After Ferguson where we saw children, disabled people, and members of the press being hit with tear gas while exercising their First Amendment rights, why are they being contained with something that we don't even use on the battlefield?"

Experts acknowledged that the treatment of tear gas under the convention is somewhat paradoxical, and it stems in part from horse-trading by convention negotiators. But they added that there are other, more substantive reasons as well.

* The use of any type of gas on a battlefield is problematic. "Part of the thinking is that soldiers in the field don't have the ability to readily distinguish in the heat of battle if a gas being used is tear gas or something more lethal," said Richard Price, a political scientist at the University of British Columbia who has studied the issues. The negotiators, he said, thought that, "as a practical matter, it was best to ban them all" on the battlefield.

* There are few immediate alternatives to tear gas for riot control. There are strategies to prevent riots, including better community relations, a less militaristic appearance, and improved training, all of which have been raised in relation to Ferguson. But once rioting is under way, police need tools to control it - and "even though tear gas is far from perfect," said David A. Koplow, a Georgetown University law professor, "it continues to be used in that role because there's nothing else better."

Israel has deployed an organic riot-control agent dubbed "skunk water," described by a BBC journalist as the "worst, most foul thing you have ever smelled. An overpowering mix of rotting meat, old socks that haven't been washed for weeks - topped off with the pungent waft of an open sewer."

However, it is sprayed from water cannons, which in the popular imagination are associated with their use against civil rights protesters in the 1960s, making them highly unsuitable for use in a scenario like the one in Ferguson. Projectiles such as rubber bullets can be effective, but they can cause serious injury or, if poorly aimed, death.

An emerging technology called the Active Denial System - or more colloquially, the "pain ray" - creates millimeter-wave frequencies that impart a searing sensation of heat on the skin, but amid concerns, the United States military has been slow to adopt it. Meanwhile, new forms of "incapacitating chemical agents" that use anesthetic chemicals have been proposed, but they have drawn the concern of such groups as the International Committee of the Red Cross.

The problem with new-generation chemical techniques, said Fidler of Indiana University, "is that their physiological effects are stronger than tear gas, which creates the potential for more injuries and other health harms. Tear gas is well understood as a riot control agent, and it seems to function well enough for law enforcement purposes.

* A lack of desire for change. There is little sign that the convention's signatories have any desire to reconcile the tear gas paradox.

"There is certainly an argument to be made that the fundamental segregation of these two issues is inherently unreasonable," said Finlay of the Stimson Center. "That said, this is very unlikely to change, as it is both a matter of treaty law as well as customary international law today. There is not much appetite among states to alter the status quo."
Our ruling
The meme said police in the United States use tear gas even though it "has been classified as a chemical weapon and banned in international conflict since 1993."

The Chemical Weapons Convention did outlaw the use of tear gas in warfare, though that went into effect in 1997, not 1993. However, the meme glosses over some context. It tries to leverage the Chemical Weapons Convention's decision to ban tear gas as evidence of why the technique should be illegal for policing, yet that very same convention explicitly allows its use for domestic law enforcement purposes.

The claim is accurate but needs clarification, so we rate it Mostly True.

Our Sources

OurTime.org, social media meme, received by PolitiFact Aug. 25, 2014

Organization for the Prohibition of Chemical Weapons, "Genesis and Historical Development," accessed Aug. 25, 2014

Centers for Disease Control and Prevention, " Facts About Riot Control Agents Interim document," accessed Aug. 25, 2014

U.S. State Department, " Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous or Other Gases, and of Bacteriological Methods of Warfare (Geneva Protocol)," accessed Aug. 24, 2014

International Committee of the Red Cross, "Chemical and biological weapons," Aug 4, 2013

Federation of American Scientists, " U.S. Ratification Timeline," accessed Aug. 25, 2014

Discover magazine, " Tear Gas: the chemical warfare agent used on demonstrators in Ferguson," Aug. 14, 2014

Wired magazine, " Video: I Got Blasted by the Pentagon's Pain Ray - Twice," March 12, 2012

Business Insider, " Tear Gas Can Cause Deaths, Amputations, and Miscarriages," Aug. 19, 2014

New York magazine, " What Are the Long-Term Health Effects of Tear Gas?," Aug. 21, 2014

Al Jazeera America, " Crowd control: Riot police techniques from Ferguson to France," Aug. 14, 2014

BBC News, " New Israeli weapon kicks up stink," Oct. 2, 2008

Email interview with David P. Fidler, Indiana University law professor, Aug. 25, 2014

Email interview with Richard Price, a political scientist at the University of British Columbia, Aug. 25, 2014

Email interview with David A. Koplow, Georgetown University law professor, Aug. 25, 2014

Email interview with Brian Finlay, managing director of the Stimson Center, Aug. 25, 2014

Email interview with James M. Acton, senior associate in the Nuclear Policy Program at the Carnegie Endowment for International Peace, Aug. 25, 2014

Email interview with Anthony Clark Arend, Georgetown University professor of government and foreign service, Aug. 25, 2014

Email interview with Jarrett Moreno, OurTime.org co-founder, Aug. 25, 2014

Browse the Truth-O-Meter

More by Louis Jacobson

Tear gas was banned for warfare in 1993 but police still use it, viral meme says

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Tear gas was banned for warfare in 1993 but police still use it, viral meme says

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Police in the United States are allowed to use tear gas even though it "has been classified as a chemical weapon and banned in international conflict since 1993."

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Henry Dunant

For much of mankind's history, the ground rules of warfare were hit or miss, if they existed at all. While some civilizations showed compassion for the injured, helpless or innocent civilians, others tortured or slaughtered anyone in sight, no questions asked.

In 1859, Genevan businessman Henry Dunant traveled to Emperor Napoleon III's headquarters in northern Italy to seek land rights for a business venture. He got much more than he bargained for, however, when he found himself a witness to the aftermath of the Battle of Solferino, a gory battle in the Second War of Italian Independence.

The horrific suffering Dunant saw impacted him so greatly he wrote a first-hand account in 1862 called A Memory of Solferino. But he didn't just write about what he'd observed, he also proposed a solution: All nations come together to create trained, volunteer relief groups to treat battlefield wounded and offer humanitarian assistance to those affected by war.

Red Cross

A committee was formed-which included Dunant and an early iteration of the Red Cross -in Geneva to explore ways to implement Dunant's ideas.

In October 1863, delegates from 16 countries along with military medical personnel traveled to Geneva to discuss the terms of a wartime humanitarian agreement. This meeting and its resultant treaty signed by 12 nations became known as the First Geneva Convention.

Despite playing an important role in the progression of what became the International Committee of the Red Cross, continuing his work as champion for the battle-wounded and prisoners of war and winning the first Nobel Peace Prize, Dunant lived and died in near poverty.

Geneva Conventions of 1906 and 1929

In 1906, the Swiss government arranged a conference of 35 states to review and update improvements to the First Geneva Convention.

The amendments extended protections for those wounded or captured in battle as well as volunteer agencies and medical personnel tasked with treating, transporting and removing the wounded and killed.

It also made the repatriation of captured belligerents a recommendation instead of mandatory. The 1906 Convention replaced the First Geneva Convention of 1864.

After World War I, it was clear the 1906 Convention and The Hague Convention of 1907 didn't go far enough. In 1929, updates were made to further the civilized treatment of prisoners of war.

The new updates stated all prisoners must be treated with compassion and live in humane conditions. It also laid out rules for the daily lives of prisoners and established the International Red Cross as the main neutral organization responsible for collecting and transmitting data about prisoners of war and the wounded or killed.

Geneva Conventions of 1949

Germany signed the Convention of 1929, however, that didn't prevent them from carrying out horrific acts on and off the battlefield and within their military prison camps and civilian concentration camps during World War II. As a result, the Geneva Conventions were expanded in 1949 to protect non-combatant civilians.

According to the American Red Cross, the new articles also added provisions to protect:

medical personnel, facilities and equipment

wounded and sick civilians accompanying military forces

military chaplains

civilians who take up arms to fight invading forces

Article 9 of the Convention specified the Red Cross has the right to assist the wounded and sick and provide humanitarian aid. Article 12 stipulated the wounded and sick must not be murdered, tortured, exterminated or exposed to biological experiments.

The Geneva Conventions of 1949 also laid out rules for protecting wounded, sick or shipwrecked armed forces at sea or on hospital ships as well as medical workers and civilians accompanying or treating military personnel. Some highlights of these rules are:

hospital ships cannot be used for any military purpose nor captured or attacked

captured religious leaders must be returned immediately

all sides must attempt to rescue any shipwrecked personnel, even those from another side of the conflict

Male and female prisoners of war received expanded protections in the Convention of 1949 such as:

they must not be tortured or mistreated

they're only required to give their name, rank, birth date and serial number when captured

they must receive suitable housing and adequate amounts of food

they must not be discriminated against for any reason

they have the right to correspond with family and receive care packages

the Red Cross has the right to visit them and examine their living conditions

Articles were also put in place to protect wounded, sick and pregnant civilians as well as mothers and children. It also stated civilians may not be collectively deported or made to work on behalf of an occupying force without pay. All civilians should receive adequate medical care and be allowed to go about their daily lives as much as possible.

Geneva Convention Protocols

In 1977, Protocols I and II were added to the Conventions of 1949. Protocol I increased protections for civilians, military workers and journalists during international armed conflicts. It also banned the use of "weapons that cause superfluous injury or unnecessary suffering," or cause "widespread, long-term and severe damage to the natural environment."

According to the Red Cross, Protocol II was established because most victims of armed conflicts since the 1949 Convention were victims of vicious civil wars. The Protocol stated all people not taking up arms be treated humanely and there should never be an order by anyone in command for "no survivors."

In addition, children should be well cared for and educated, and the following is prohibited:

taking hostages

terrorism

pillage

slavery

group punishment

humiliating or degrading treatment

In 2005, a Protocol was created to recognize the symbol of the red crystal-in addition to the red cross, the red crescent and the red shield of David-as universal emblems of identification and protection in armed conflicts.

Over 190 states follow the Geneva Conventions because of the belief that some battlefield behaviors are so heinous and damaging, they harm the entire international community. The rules help draw a line-as much as is possible within the context of wars and armed conflicts-between the humane treatment of armed forces, medical staff and civilians and unrestrained brutality against them.

Sources

Geneva Convention of 27 July 1929 relative to the treatment of prisoners of war. International Committee of the Red Cross.
Geneva Conventions. Cornell Law School Legal Information Institute.
Henry Dunant Biographical. Nobelprize.org.
History of the Geneva Conventions. PBS.org.
Summary of the Geneva Conventions of 1949 and Their Additional Protocols. American Red Cross.
The Battle of Solferino. British Red Cross.
Treaties, States Parties, and Commentaries: Convention for the Amelioration of the Condition of the Wounded and Sick in Armies in the Field. Geneva, 6 July 1906. International Committee of the Red Cross.
Treaties, States, Parties, and Commentaries: Protocol Additional to the Geneva Conventions of 12 August 1949, and relating to the Protection of Victims of International Armed Conflicts (Protocol I), 8 June 1977. International Committee of the Red Cross.
Treaties, States Parties, and Commentaries: Protocol Additional to the Geneva Conventions of 12 August 1949, and relating to the Protection of Victims of Non-International Armed Conflicts (Protocol II), 8 June 1977. International Committee of the Red Cross.

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For much of mankind's history, the ground rules of warfare were hit or miss, if they existed at all. While some civilizations showed compassion for the injured, helpless or innocent civilians, others tortured or slaughtered anyone in sight, no questions asked.

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Defense against chemical weapons

On the battlefield

Since World War I the military organizations of all the great powers have acquired defensive equipment to cope with emerging offensive chemical weapons. The first and most important line of defense against chemical agents is the individual protection provided by gas masks and protective clothing and the collective protection of combat vehicles and mobile or fixed shelters. Filters for masks and shelters contain specially treated activated charcoal, to remove vapours, and paper membranes or other materials, to remove particles. Such filters typically can reduce the concentration of chemical agents by a factor of at least 100,000. Masks can be donned in less than 10 seconds and can be worn for long periods, even in sleep. Modern protective overgarments are made of fabric containing activated charcoal or other adsorptive forms of carbon. A complete suit typically weighs about 2 kg (4.4 pounds). The fabric can breathe and pass water-vapour perspiration. In warm weather, periods of heavy exertion in full protective gear would have to be limited in order to avoid heat stress. Also, removing such gear in a contaminated environment would raise the risk of becoming a casualty or fatality, and so gear must be removed within toxic-free shelters after following decontamination procedures at the shelter entrance.

© Larry St. Pierre/Shutterstock.com

Chemical detectors have been developed to help identify levels and places of contamination. These include chemically treated litmus paper used to determine the presence of chemical agents. Other sensors may include handheld assays, vehicles equipped with scoops and laboratory analysis tools, and both point and standoff sensors. Automatic field alarm systems are employed by some military forces to alert personnel to the presence of chemical agents.

Well-equipped troops are supplied with hypodermic needles filled with antidotes to be administered in the event of toxic poisoning from nerve agents. For example, atropine shots can be injected to fight the effects of nerve gas exposures, and different medicines are available to treat casualties.

A number of methods have been found useful in decontaminating areas and people covered with chemical agents, including spraying with super tropical bleach (chlorinated lime) or washing contaminated surfaces or garments with warm soapy water. The challenge is finding and using a decontamination solution that is strong enough to neutralize the chemical agent without damaging the equipment or harming the personnel.

In some military forces, modular field hospitals have been developed that are stocked with resuscitation devices for respiratory support and other necessary equipment, decontamination solutions, and staff trained to decontaminate chemical warfare casualties. Collective protective shelters, complete with filters for airflow systems, have been provided to shield personnel in an otherwise contaminated area. Such shelters can provide a toxic-free area for personnel to change clothes, get medical attention, sleep, and take care of bodily functions with less danger of exposure to lethal chemicals.

Chemical agents used against unprotected forces can cause high casualties, fear, and confusion. Thus, personnel facing adversaries equipped with chemical weapons must be trained to don individual protective equipment, seek cover in collective protection shelters, avoid contaminated areas, and rapidly decontaminate personnel and equipment that have been exposed. However, such measures, while necessary to protect against chemical attacks, may expose protected forces to greater casualties from conventional weapons fire and lead to a loss of conventional combat effectiveness. Indeed, exercises have shown that conventional combat effectiveness can be decreased by 25 percent or more for military forces compelled to operate in masks, protective overgarments, special gloves, and boots. This is especially true if temperatures are high and forces are required to stay sealed in their gear for many hours or days without relief. Prolonged wearing of individual protective equipment can lead to stress, fatigue, disorientation, confusion, frustration, and irritability. Also, heat can build up and lead to dehydration. Thus, there is generally a trade-off between protecting one's force through chemical-protection gear and maintaining conventional fighting effectiveness.

In civilian defense

While most military forces have at least some defense against chemical attack, this is not the case for most civilian populations, which typically have no individual protective equipment (masks, overgarments, boots, or gloves) or collective protection shelters. One notable exception is Israel, which has been at war numerous times since its independence in 1948. Israeli citizens are assigned their own gas masks, and new buildings in Israel must contain a reinforced shelter. Israel also conducts civil defense exercises on a regular basis in order to prepare its citizens for attack.

A further problem for almost every country is the presence in most urban centres of storage or manufacturing facilities that contain toxic industrial chemicals and other toxic materials. A conventional attack on such a site would be the functional equivalent of a chemical weapons attack. Most countries do not have adequate security around such areas.

One response to the threat of a chemical weapons attack on civilian society has been the creation of active, well-trained emergency response teams that know how to identify chemical agents, decontaminate areas and people exposed to chemical weapons, and coordinate rescue operations. Cognizant of the growing risk posed by weapons of mass destruction (WMD), the United States in 1998 authorized the creation of 10 National Guard WMD Civil Support Teams (WMD-CST) within its territory; each team was organized, trained, and equipped to handle chemical emergencies in support of local police, firefighters, medical personnel, and other first responders. In subsequent years, dozens of new WMD-CST were authorized, with plans for eventually certifying units for every state and some U.S. protectorates. In addition, the U.S. Centers for Disease Control and Prevention maintains the Strategic National Stockpile, which contains medical supplies and equipment positioned around the country to provide medical help in emergencies, including a chemical weapons attack.

Chemical weapons in history

Antiquity

The use of chemical weapons dates back to antiquity, when warring forces frequently poisoned the water supplies of their adversaries. For example, the Athenians poisoned the wells of their rivals as early as 600 bce, and the Spartans, their chief antagonists, in turn hurled burning sulfur pitch over the walls of Athens in 423 bce. In 673 ce the Byzantines defended Constantinople from the Saracen navy by igniting chemicals (known as Greek fire) floating in the sea. During the Middle Ages, Genghis Khan 's Mongolian forces employed chemical warfare when they catapulted burning pitch and sulfur into cities they besieged.

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Chemical weapon - Defense against chemical weapons

# data[].attributes.attachment_link.description
Chemical weapon - Defense against chemical weapons: Since World War I the military organizations of all the great powers have acquired defensive equipment to cope with emerging offensive chemical weapons. The first and most important line of defense against chemical agents is the individual protection provided by gas masks and protective clothing and the collective protection of combat vehicles and mobile or fixed shelters.

# data[].attributes.attachment_link.readable_text
Defense against chemical weapons

On the battlefield

Since World War I the military organizations of all the great powers have acquired defensive equipment to cope with emerging offensive chemical weapons. The first and most important line of defense against chemical agents is the individual protection provided by gas masks and protective clothing and the collective protection of combat vehicles and mobile or fixed shelters. Filters for masks and shelters contain specially treated activated charcoal, to remove vapours, and paper membranes or other materials, to remove particles. Such filters typically can reduce the concentration of chemical agents by a factor of at least 100,000. Masks can be donned in less than 10 seconds and can be worn for long periods, even in sleep. Modern protective overgarments are made of fabric containing activated charcoal or other adsorptive forms of carbon. A complete suit typically weighs about 2 kg (4.4 pounds). The fabric can breathe and pass water-vapour perspiration. In warm weather, periods of heavy exertion in full protective gear would have to be limited in order to avoid heat stress. Also, removing such gear in a contaminated environment would raise the risk of becoming a casualty or fatality, and so gear must be removed within toxic-free shelters after following decontamination procedures at the shelter entrance.

© Larry St. Pierre/Shutterstock.com

Chemical detectors have been developed to help identify levels and places of contamination. These include chemically treated litmus paper used to determine the presence of chemical agents. Other sensors may include handheld assays, vehicles equipped with scoops and laboratory analysis tools, and both point and standoff sensors. Automatic field alarm systems are employed by some military forces to alert personnel to the presence of chemical agents.

Well-equipped troops are supplied with hypodermic needles filled with antidotes to be administered in the event of toxic poisoning from nerve agents. For example, atropine shots can be injected to fight the effects of nerve gas exposures, and different medicines are available to treat casualties.

A number of methods have been found useful in decontaminating areas and people covered with chemical agents, including spraying with super tropical bleach (chlorinated lime) or washing contaminated surfaces or garments with warm soapy water. The challenge is finding and using a decontamination solution that is strong enough to neutralize the chemical agent without damaging the equipment or harming the personnel.

In some military forces, modular field hospitals have been developed that are stocked with resuscitation devices for respiratory support and other necessary equipment, decontamination solutions, and staff trained to decontaminate chemical warfare casualties. Collective protective shelters, complete with filters for airflow systems, have been provided to shield personnel in an otherwise contaminated area. Such shelters can provide a toxic-free area for personnel to change clothes, get medical attention, sleep, and take care of bodily functions with less danger of exposure to lethal chemicals.

Chemical agents used against unprotected forces can cause high casualties, fear, and confusion. Thus, personnel facing adversaries equipped with chemical weapons must be trained to don individual protective equipment, seek cover in collective protection shelters, avoid contaminated areas, and rapidly decontaminate personnel and equipment that have been exposed. However, such measures, while necessary to protect against chemical attacks, may expose protected forces to greater casualties from conventional weapons fire and lead to a loss of conventional combat effectiveness. Indeed, exercises have shown that conventional combat effectiveness can be decreased by 25 percent or more for military forces compelled to operate in masks, protective overgarments, special gloves, and boots. This is especially true if temperatures are high and forces are required to stay sealed in their gear for many hours or days without relief. Prolonged wearing of individual protective equipment can lead to stress, fatigue, disorientation, confusion, frustration, and irritability. Also, heat can build up and lead to dehydration. Thus, there is generally a trade-off between protecting one's force through chemical-protection gear and maintaining conventional fighting effectiveness.

In civilian defense

While most military forces have at least some defense against chemical attack, this is not the case for most civilian populations, which typically have no individual protective equipment (masks, overgarments, boots, or gloves) or collective protection shelters. One notable exception is Israel, which has been at war numerous times since its independence in 1948. Israeli citizens are assigned their own gas masks, and new buildings in Israel must contain a reinforced shelter. Israel also conducts civil defense exercises on a regular basis in order to prepare its citizens for attack.

A further problem for almost every country is the presence in most urban centres of storage or manufacturing facilities that contain toxic industrial chemicals and other toxic materials. A conventional attack on such a site would be the functional equivalent of a chemical weapons attack. Most countries do not have adequate security around such areas.

One response to the threat of a chemical weapons attack on civilian society has been the creation of active, well-trained emergency response teams that know how to identify chemical agents, decontaminate areas and people exposed to chemical weapons, and coordinate rescue operations. Cognizant of the growing risk posed by weapons of mass destruction (WMD), the United States in 1998 authorized the creation of 10 National Guard WMD Civil Support Teams (WMD-CST) within its territory; each team was organized, trained, and equipped to handle chemical emergencies in support of local police, firefighters, medical personnel, and other first responders. In subsequent years, dozens of new WMD-CST were authorized, with plans for eventually certifying units for every state and some U.S. protectorates. In addition, the U.S. Centers for Disease Control and Prevention maintains the Strategic National Stockpile, which contains medical supplies and equipment positioned around the country to provide medical help in emergencies, including a chemical weapons attack.

Chemical weapons in history

Antiquity

The use of chemical weapons dates back to antiquity, when warring forces frequently poisoned the water supplies of their adversaries. For example, the Athenians poisoned the wells of their rivals as early as 600 bce, and the Spartans, their chief antagonists, in turn hurled burning sulfur pitch over the walls of Athens in 423 bce. In 673 ce the Byzantines defended Constantinople from the Saracen navy by igniting chemicals (known as Greek fire) floating in the sea. During the Middle Ages, Genghis Khan 's Mongolian forces employed chemical warfare when they catapulted burning pitch and sulfur into cities they besieged.

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Chemical weapon - Defense against chemical weapons

# data[].attributes.attachment_link.description
Chemical weapon - Defense against chemical weapons: Since World War I the military organizations of all the great powers have acquired defensive equipment to cope with emerging offensive chemical weapons. The first and most important line of defense against chemical agents is the individual protection provided by gas masks and protective clothing and the collective protection of combat vehicles and mobile or fixed shelters.

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Chemical weapon - WMD, Toxins, Agents | Britannica

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Chemical weapon - WMD, Toxins, Agents: Chemical weapons did not become true weapons of mass destruction (WMD) until they were introduced in their modern form in World War I (1914–18). The German army initiated modern chemical warfare by launching a chlorine attack at Ypres, Belgium, on April 22, 1915, killing 5,000 French and Algerian troops and momentarily breaching their lines of defense. German use of gas and mustard was soon countered by similar tactics from the Allies. By war’s end, both sides had used massive quantities of chemical weapons, causing an estimated 1,300,000 casualties, including 91,000 fatalities. The Russian army suffered about 500,000 of these casualties,

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Banning chemical weapons

During World War I, Germany, France, the United Kingdom, and Russia developed a wide array of chemical arms, including choking, blister, blood, and irritant agents. During World War II, Germany developed nerve agents such as toman, soman, and sarin. After World War II, the British invented VX, a more persistent nerve agent that eventually was deployed by the United States and the Soviet Union.

The World War I chemical agents are referred to as first-generation weapons, the World War II nerve agents are called second-generation weapons, and Cold War chemical agents (such as VX) are known as third-generation weapons. Part of the U.S. arsenal during the Cold War also included CS, a riot-control agent, and BZ, an incapacitant, as well as sarin and VX. The Soviet Union also had a complete chemical weapons arsenal, including "classic" agents from the first, second, and third generation, all of which are now banned by the CWC.

According to some interpretations, the CWC does not cover fourth-generation chemical weapons, so-called nontraditional agents (NTAs), such as some of the binary nerve agents known as "novichoks." There is evidence that Russia inherited NTAs from the former Soviet arsenals.

Negotiations to secure a multilateral chemical disarmament treaty began in the early 1960s at the United Nations. Issues that separated the sides were the kinds of verification procedures for checking on treaty compliance, whether all or part of the weapons stocks should be dismantled, and the sanctions to be levied against violators. Real progress did not take place until the period 1986-91, when relations between the Soviet Union and the United States improved after the rise to power of Soviet leader Mikhail Gorbachev. With the dissolution first of the Warsaw Pact in 1989 and then of the Soviet Union itself in 1991, a real convergence of political and diplomatic views was made possible. In 1990 bilateral reductions and limits were negotiated in which each state agreed to a limit of 5,000 tons of chemical agents in its chemical weapons arsenal. By 1993 the former enemies were finally willing to agree to a robust on-site verification regime featuring challenge inspections of undeclared sites, a total ban on chemical weapons, and a total dismantling of their stockpiles.

The United Nations Conference on Disarmament adopted the Chemical Weapons Convention (CWC) on September 3, 1992, and the treaty was opened to signature by all states on January 13, 1993. The CWC entered into force on April 29, 1997, 180 days after the deposit of the 65th instrument of ratification (such as passage by a national assembly).

At the time that the United States and Russia signed the CWC, Russia declared 40,000 metric tons of chemical weapon agents and the United States 30,000 metric tons-stockpiles that dwarfed the combined arsenals of the rest of the world. All were to be destroyed, according to CWC guidelines, by the year 2012. In the early 1990s the U.S. Cooperative Threat Reduction Program was launched to help the states of the former Soviet Union demilitarize their chemical, biological, and nuclear facilities and arsenals and to employ the scientists and technicians from those programs in other, more productive peacetime activities. Despite such efforts, both countries fell behind schedule and announced that they would not be able to meet the 2012 deadline. The United States was on a trajectory to finish the job by 2021, and Russia declared it would finish its parallel effort in 2015.

All other signatories to the CWC reportedly eliminated their stockpiles, though some states subsequently declared stockpiles that they had previously denied existed. Libya is a case in point. In 2004 Libya decided to part with its chemical and nuclear weapons programs and invited the United States and the United Kingdom to help it dismantle both. Significant progress was made in destroying mustard gas and precursors to other chemical weapons before Libya was paralyzed by civil strife in 2011.

United Nations inspection teams entered Iraq after the Persian Gulf War ended in early 1991. Some 40,000 Iraqi chemical weapons were then found and destroyed, and a bunker containing thousands of possibly war-damaged weapons was sealed. After the U.S. invasion of Iraq in 2003, no major stockpile of chemical weapons or dedicated facilities for their manufacture were found in Iraq, contrary to the United States' contention before the invasion. A very few chemical rounds were found among arms storage sites in Iraq, but they were thought to be left over from the Iran-Iraq War. Upon becoming a signatory to the CWC in 2009, Iraq acknowledged its obligation to dispose of its remaining damaged weapons-a complicated and dangerous effort that would take years to complete.

Proliferation and detection of chemical weapons programs

Chemical weapons proliferation

The Chemical Weapons Convention has resulted in the elimination of huge stocks of chemical weapons once held by the principal adversaries of the Cold War. Nevertheless, intelligence services of various countries have reported an increase in the number of states with active chemical weapons programs. Some 20 countries were reportedly working on chemical weapons at the beginning of the 21st century, as opposed to only five such states in the 1960s.

Regimes seek to acquire chemical weapons for a number of reasons. First, they may decide that having such lethal weapons will allow them to "level the playing field" against an adversary with a stronger conventional military force. Second, they may wish to deter attacks by rivals, holding them at bay with the threat of a chemical weapons strike in retaliation. Having one type of weapon of mass destruction might deter the use of the same or another type by a rival. Third, chemical weapons, like other mass-casualty weapons such as nuclear and biological arms, may be designed for regime survival in the event that a country is losing a conventional conflict. In this case, possession of chemical warfare capabilities might provide endgame bargaining leverage to establish better terms. For example, in the Iran-Iraq War, Iraq's use of Scud ballistic missiles (with the potential to deliver chemical warheads) against Iranian cities caused major panic in those metropolitan centres and helped persuade the Iranian government to agree to a cease-fire sought by Iraq. Fourth, chemicals can be used as terror weapons to lower enemy morale and weaken support for the rival's war effort. Finally, chemical weapons can be used against unprotected rebellious groups inside a country, as Ṣaddām Ḥussein illustrated in his chemical weapon strikes against the Kurdish city of Halabjah.

Detection of clandestine programs

Although most states have joined the CWC, some member states may still cheat and deploy a clandestine chemical weapons program. Inspectors from the Organisation for the Prohibition of Chemical Weapons (OPCW; the body that administers the CWC) number only in the hundreds, whereas the estimated number of chemical plants that might be inspected exceed many thousands. Therefore, only a small fraction of sites can be inspected every year. Still other states, notably Israel and some of its Arab rivals, refuse to ratify the various nuclear, biological, and chemical nonproliferation pacts until their rivals eliminate their own (undeclared) arsenals and join the respective arms-control treaty regimes.

This leads to the question of how a clandestine chemical weapons program can be detected and measured. Using technical means, human intelligence, and on-site inspections, chemical weapons program signatures can be monitored when searching for a hidden cache of weapons or a production process. These signatures include purchases of unique combinations of chemical precursors and equipment, the presence of equipment for chemical weaponization, and the presence of chemical warfare defensive gear in military units. Other signatures are the discovery of trace amounts of chemical warfare agents or chemical weapons degradation products at a production site or in a plant's waste products. Finally, signatures may be the presence of storage bunkers, related manufacturing facilities needed for chemical weaponization, or even the presence of a chemical plant with abnormal input-output flows of materials. Nevertheless, detection of clandestine chemical weapons, banned by the CWC or otherwise, is a difficult challenge, since chemical weapons production can be embedded in commercial chemical production plants and evidence can be eliminated in a short period prior to permitting inspectors onto a site-if they are allowed on at all.

The Australia Group is a standing diplomatic conference made up of representatives from states dedicated to restraining the proliferation of key materials and technologies that could be used to produce chemical or biological weapons. Since its formation in 1985, members of the organization have exchanged information and cooperated with one another to control such exports to suspect buyers. The Australia Group is a strictly voluntary and informal export control regime with no formal guidelines, charter, or constitution.

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Chemical weapon - Banning chemical weapons

# data[].attributes.attachment_link.description
Chemical weapon - Banning chemical weapons: During World War I, Germany, France, the United Kingdom, and Russia developed a wide array of chemical arms, including choking, blister, blood, and irritant agents. During World War II, Germany developed nerve agents such as toman, soman, and sarin.

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Banning chemical weapons

During World War I, Germany, France, the United Kingdom, and Russia developed a wide array of chemical arms, including choking, blister, blood, and irritant agents. During World War II, Germany developed nerve agents such as toman, soman, and sarin. After World War II, the British invented VX, a more persistent nerve agent that eventually was deployed by the United States and the Soviet Union.

The World War I chemical agents are referred to as first-generation weapons, the World War II nerve agents are called second-generation weapons, and Cold War chemical agents (such as VX) are known as third-generation weapons. Part of the U.S. arsenal during the Cold War also included CS, a riot-control agent, and BZ, an incapacitant, as well as sarin and VX. The Soviet Union also had a complete chemical weapons arsenal, including "classic" agents from the first, second, and third generation, all of which are now banned by the CWC.

According to some interpretations, the CWC does not cover fourth-generation chemical weapons, so-called nontraditional agents (NTAs), such as some of the binary nerve agents known as "novichoks." There is evidence that Russia inherited NTAs from the former Soviet arsenals.

Negotiations to secure a multilateral chemical disarmament treaty began in the early 1960s at the United Nations. Issues that separated the sides were the kinds of verification procedures for checking on treaty compliance, whether all or part of the weapons stocks should be dismantled, and the sanctions to be levied against violators. Real progress did not take place until the period 1986-91, when relations between the Soviet Union and the United States improved after the rise to power of Soviet leader Mikhail Gorbachev. With the dissolution first of the Warsaw Pact in 1989 and then of the Soviet Union itself in 1991, a real convergence of political and diplomatic views was made possible. In 1990 bilateral reductions and limits were negotiated in which each state agreed to a limit of 5,000 tons of chemical agents in its chemical weapons arsenal. By 1993 the former enemies were finally willing to agree to a robust on-site verification regime featuring challenge inspections of undeclared sites, a total ban on chemical weapons, and a total dismantling of their stockpiles.

The United Nations Conference on Disarmament adopted the Chemical Weapons Convention (CWC) on September 3, 1992, and the treaty was opened to signature by all states on January 13, 1993. The CWC entered into force on April 29, 1997, 180 days after the deposit of the 65th instrument of ratification (such as passage by a national assembly).

At the time that the United States and Russia signed the CWC, Russia declared 40,000 metric tons of chemical weapon agents and the United States 30,000 metric tons-stockpiles that dwarfed the combined arsenals of the rest of the world. All were to be destroyed, according to CWC guidelines, by the year 2012. In the early 1990s the U.S. Cooperative Threat Reduction Program was launched to help the states of the former Soviet Union demilitarize their chemical, biological, and nuclear facilities and arsenals and to employ the scientists and technicians from those programs in other, more productive peacetime activities. Despite such efforts, both countries fell behind schedule and announced that they would not be able to meet the 2012 deadline. The United States was on a trajectory to finish the job by 2021, and Russia declared it would finish its parallel effort in 2015.

All other signatories to the CWC reportedly eliminated their stockpiles, though some states subsequently declared stockpiles that they had previously denied existed. Libya is a case in point. In 2004 Libya decided to part with its chemical and nuclear weapons programs and invited the United States and the United Kingdom to help it dismantle both. Significant progress was made in destroying mustard gas and precursors to other chemical weapons before Libya was paralyzed by civil strife in 2011.

United Nations inspection teams entered Iraq after the Persian Gulf War ended in early 1991. Some 40,000 Iraqi chemical weapons were then found and destroyed, and a bunker containing thousands of possibly war-damaged weapons was sealed. After the U.S. invasion of Iraq in 2003, no major stockpile of chemical weapons or dedicated facilities for their manufacture were found in Iraq, contrary to the United States' contention before the invasion. A very few chemical rounds were found among arms storage sites in Iraq, but they were thought to be left over from the Iran-Iraq War. Upon becoming a signatory to the CWC in 2009, Iraq acknowledged its obligation to dispose of its remaining damaged weapons-a complicated and dangerous effort that would take years to complete.

Proliferation and detection of chemical weapons programs

Chemical weapons proliferation

The Chemical Weapons Convention has resulted in the elimination of huge stocks of chemical weapons once held by the principal adversaries of the Cold War. Nevertheless, intelligence services of various countries have reported an increase in the number of states with active chemical weapons programs. Some 20 countries were reportedly working on chemical weapons at the beginning of the 21st century, as opposed to only five such states in the 1960s.

Regimes seek to acquire chemical weapons for a number of reasons. First, they may decide that having such lethal weapons will allow them to "level the playing field" against an adversary with a stronger conventional military force. Second, they may wish to deter attacks by rivals, holding them at bay with the threat of a chemical weapons strike in retaliation. Having one type of weapon of mass destruction might deter the use of the same or another type by a rival. Third, chemical weapons, like other mass-casualty weapons such as nuclear and biological arms, may be designed for regime survival in the event that a country is losing a conventional conflict. In this case, possession of chemical warfare capabilities might provide endgame bargaining leverage to establish better terms. For example, in the Iran-Iraq War, Iraq's use of Scud ballistic missiles (with the potential to deliver chemical warheads) against Iranian cities caused major panic in those metropolitan centres and helped persuade the Iranian government to agree to a cease-fire sought by Iraq. Fourth, chemicals can be used as terror weapons to lower enemy morale and weaken support for the rival's war effort. Finally, chemical weapons can be used against unprotected rebellious groups inside a country, as Ṣaddām Ḥussein illustrated in his chemical weapon strikes against the Kurdish city of Halabjah.

Detection of clandestine programs

Although most states have joined the CWC, some member states may still cheat and deploy a clandestine chemical weapons program. Inspectors from the Organisation for the Prohibition of Chemical Weapons (OPCW; the body that administers the CWC) number only in the hundreds, whereas the estimated number of chemical plants that might be inspected exceed many thousands. Therefore, only a small fraction of sites can be inspected every year. Still other states, notably Israel and some of its Arab rivals, refuse to ratify the various nuclear, biological, and chemical nonproliferation pacts until their rivals eliminate their own (undeclared) arsenals and join the respective arms-control treaty regimes.

This leads to the question of how a clandestine chemical weapons program can be detected and measured. Using technical means, human intelligence, and on-site inspections, chemical weapons program signatures can be monitored when searching for a hidden cache of weapons or a production process. These signatures include purchases of unique combinations of chemical precursors and equipment, the presence of equipment for chemical weaponization, and the presence of chemical warfare defensive gear in military units. Other signatures are the discovery of trace amounts of chemical warfare agents or chemical weapons degradation products at a production site or in a plant's waste products. Finally, signatures may be the presence of storage bunkers, related manufacturing facilities needed for chemical weaponization, or even the presence of a chemical plant with abnormal input-output flows of materials. Nevertheless, detection of clandestine chemical weapons, banned by the CWC or otherwise, is a difficult challenge, since chemical weapons production can be embedded in commercial chemical production plants and evidence can be eliminated in a short period prior to permitting inspectors onto a site-if they are allowed on at all.

The Australia Group is a standing diplomatic conference made up of representatives from states dedicated to restraining the proliferation of key materials and technologies that could be used to produce chemical or biological weapons. Since its formation in 1985, members of the organization have exchanged information and cooperated with one another to control such exports to suspect buyers. The Australia Group is a strictly voluntary and informal export control regime with no formal guidelines, charter, or constitution.

# data[].attributes.attachment_link.title
Chemical weapon - Banning chemical weapons

# data[].attributes.attachment_link.description
Chemical weapon - Banning chemical weapons: During World War I, Germany, France, the United Kingdom, and Russia developed a wide array of chemical arms, including choking, blister, blood, and irritant agents. During World War II, Germany developed nerve agents such as toman, soman, and sarin.

# data[].attributes.attachment_link.readable_text
Banning chemical weapons

During World War I, Germany, France, the United Kingdom, and Russia developed a wide array of chemical arms, including choking, blister, blood, and irritant agents. During World War II, Germany developed nerve agents such as toman, soman, and sarin. After World War II, the British invented VX, a more persistent nerve agent that eventually was deployed by the United States and the Soviet Union.

The World War I chemical agents are referred to as first-generation weapons, the World War II nerve agents are called second-generation weapons, and Cold War chemical agents (such as VX) are known as third-generation weapons. Part of the U.S. arsenal during the Cold War also included CS, a riot-control agent, and BZ, an incapacitant, as well as sarin and VX. The Soviet Union also had a complete chemical weapons arsenal, including "classic" agents from the first, second, and third generation, all of which are now banned by the CWC.

According to some interpretations, the CWC does not cover fourth-generation chemical weapons, so-called nontraditional agents (NTAs), such as some of the binary nerve agents known as "novichoks." There is evidence that Russia inherited NTAs from the former Soviet arsenals.

Negotiations to secure a multilateral chemical disarmament treaty began in the early 1960s at the United Nations. Issues that separated the sides were the kinds of verification procedures for checking on treaty compliance, whether all or part of the weapons stocks should be dismantled, and the sanctions to be levied against violators. Real progress did not take place until the period 1986-91, when relations between the Soviet Union and the United States improved after the rise to power of Soviet leader Mikhail Gorbachev. With the dissolution first of the Warsaw Pact in 1989 and then of the Soviet Union itself in 1991, a real convergence of political and diplomatic views was made possible. In 1990 bilateral reductions and limits were negotiated in which each state agreed to a limit of 5,000 tons of chemical agents in its chemical weapons arsenal. By 1993 the former enemies were finally willing to agree to a robust on-site verification regime featuring challenge inspections of undeclared sites, a total ban on chemical weapons, and a total dismantling of their stockpiles.

The United Nations Conference on Disarmament adopted the Chemical Weapons Convention (CWC) on September 3, 1992, and the treaty was opened to signature by all states on January 13, 1993. The CWC entered into force on April 29, 1997, 180 days after the deposit of the 65th instrument of ratification (such as passage by a national assembly).

At the time that the United States and Russia signed the CWC, Russia declared 40,000 metric tons of chemical weapon agents and the United States 30,000 metric tons-stockpiles that dwarfed the combined arsenals of the rest of the world. All were to be destroyed, according to CWC guidelines, by the year 2012. In the early 1990s the U.S. Cooperative Threat Reduction Program was launched to help the states of the former Soviet Union demilitarize their chemical, biological, and nuclear facilities and arsenals and to employ the scientists and technicians from those programs in other, more productive peacetime activities. Despite such efforts, both countries fell behind schedule and announced that they would not be able to meet the 2012 deadline. The United States was on a trajectory to finish the job by 2021, and Russia declared it would finish its parallel effort in 2015.

All other signatories to the CWC reportedly eliminated their stockpiles, though some states subsequently declared stockpiles that they had previously denied existed. Libya is a case in point. In 2004 Libya decided to part with its chemical and nuclear weapons programs and invited the United States and the United Kingdom to help it dismantle both. Significant progress was made in destroying mustard gas and precursors to other chemical weapons before Libya was paralyzed by civil strife in 2011.

United Nations inspection teams entered Iraq after the Persian Gulf War ended in early 1991. Some 40,000 Iraqi chemical weapons were then found and destroyed, and a bunker containing thousands of possibly war-damaged weapons was sealed. After the U.S. invasion of Iraq in 2003, no major stockpile of chemical weapons or dedicated facilities for their manufacture were found in Iraq, contrary to the United States' contention before the invasion. A very few chemical rounds were found among arms storage sites in Iraq, but they were thought to be left over from the Iran-Iraq War. Upon becoming a signatory to the CWC in 2009, Iraq acknowledged its obligation to dispose of its remaining damaged weapons-a complicated and dangerous effort that would take years to complete.

Proliferation and detection of chemical weapons programs

Chemical weapons proliferation

The Chemical Weapons Convention has resulted in the elimination of huge stocks of chemical weapons once held by the principal adversaries of the Cold War. Nevertheless, intelligence services of various countries have reported an increase in the number of states with active chemical weapons programs. Some 20 countries were reportedly working on chemical weapons at the beginning of the 21st century, as opposed to only five such states in the 1960s.

Regimes seek to acquire chemical weapons for a number of reasons. First, they may decide that having such lethal weapons will allow them to "level the playing field" against an adversary with a stronger conventional military force. Second, they may wish to deter attacks by rivals, holding them at bay with the threat of a chemical weapons strike in retaliation. Having one type of weapon of mass destruction might deter the use of the same or another type by a rival. Third, chemical weapons, like other mass-casualty weapons such as nuclear and biological arms, may be designed for regime survival in the event that a country is losing a conventional conflict. In this case, possession of chemical warfare capabilities might provide endgame bargaining leverage to establish better terms. For example, in the Iran-Iraq War, Iraq's use of Scud ballistic missiles (with the potential to deliver chemical warheads) against Iranian cities caused major panic in those metropolitan centres and helped persuade the Iranian government to agree to a cease-fire sought by Iraq. Fourth, chemicals can be used as terror weapons to lower enemy morale and weaken support for the rival's war effort. Finally, chemical weapons can be used against unprotected rebellious groups inside a country, as Ṣaddām Ḥussein illustrated in his chemical weapon strikes against the Kurdish city of Halabjah.

Detection of clandestine programs

Although most states have joined the CWC, some member states may still cheat and deploy a clandestine chemical weapons program. Inspectors from the Organisation for the Prohibition of Chemical Weapons (OPCW; the body that administers the CWC) number only in the hundreds, whereas the estimated number of chemical plants that might be inspected exceed many thousands. Therefore, only a small fraction of sites can be inspected every year. Still other states, notably Israel and some of its Arab rivals, refuse to ratify the various nuclear, biological, and chemical nonproliferation pacts until their rivals eliminate their own (undeclared) arsenals and join the respective arms-control treaty regimes.

This leads to the question of how a clandestine chemical weapons program can be detected and measured. Using technical means, human intelligence, and on-site inspections, chemical weapons program signatures can be monitored when searching for a hidden cache of weapons or a production process. These signatures include purchases of unique combinations of chemical precursors and equipment, the presence of equipment for chemical weaponization, and the presence of chemical warfare defensive gear in military units. Other signatures are the discovery of trace amounts of chemical warfare agents or chemical weapons degradation products at a production site or in a plant's waste products. Finally, signatures may be the presence of storage bunkers, related manufacturing facilities needed for chemical weaponization, or even the presence of a chemical plant with abnormal input-output flows of materials. Nevertheless, detection of clandestine chemical weapons, banned by the CWC or otherwise, is a difficult challenge, since chemical weapons production can be embedded in commercial chemical production plants and evidence can be eliminated in a short period prior to permitting inspectors onto a site-if they are allowed on at all.

The Australia Group is a standing diplomatic conference made up of representatives from states dedicated to restraining the proliferation of key materials and technologies that could be used to produce chemical or biological weapons. Since its formation in 1985, members of the organization have exchanged information and cooperated with one another to control such exports to suspect buyers. The Australia Group is a strictly voluntary and informal export control regime with no formal guidelines, charter, or constitution.

# data[].attributes.attachment_link.title
Chemical weapon - Banning chemical weapons

# data[].attributes.attachment_link.description
Chemical weapon - Banning chemical weapons: During World War I, Germany, France, the United Kingdom, and Russia developed a wide array of chemical arms, including choking, blister, blood, and irritant agents. During World War II, Germany developed nerve agents such as toman, soman, and sarin.

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Chemical weapons and terrorism

Until the 1990s, terrorists had rarely possessed or employed chemical weapons. However, several states that have sponsored terrorism have also possessed chemical weapons-Libya, Iran, and Iraq-and there is a concern that they and groups they sponsor might use chemical weapons in the future.

An example of an organization that learned to produce and use chemical weapons is the AUM Shinrikyo sect in Japan, members of which used sarin nerve agent to kill 12 people and injure more than 1,000 in a March 1995 chemical weapons attack inside the Tokyo subway system. Members of this same group had killed seven and injured more than 300 in a June 1994 attack in Matsumoto, Japan. They also assassinated one opponent using VX nerve agent in Osaka and injured another by the same means in Tokyo in early 1995. Finally, in May and July 1995, members of the AUM Shinrikyo used hydrogen cyanide in two follow-up strikes in the Tokyo subway that injured four persons. Altogether, the several attacks with three different types of chemical weapons killed 20 people, injured some 1,300, and sent more than 5,600 to the hospital for examination. Casualties would likely have been much higher had the Japanese police not intervened when they did.

Al-Qaeda leaders have shown an interest in acquiring and employing chemical weapons, as indicated by experiments testing the use of hydrogen cyanide on animals in al-Qaeda camps in Afghanistan prior to the September 11 attacks on the United States in 2001. In addition to other documents showing ongoing research on chemical weapons, al-Qaeda planned and then aborted a chemical attack on the New York City subway system in 2005. Furthermore, al-Qaeda of Mesopotamia (also known as al-Qaeda of Iraq) initiated chlorine attacks in Iraq in 2007. It is believed by some Western analysts that al-Qaeda leaders would not hesitate to use any chemical, biological, radiological, or nuclear weapons that they might acquire. For example, al-Qaeda of Mesopotamia openly issued a public invitation for Muslim chemists, biologists, and physicists to join their cause.

Unfortunately, a substantial amount of information on how to manufacture chemical weapons already exists in the public domain, particularly on the Internet, which is within reach of individuals and groups worldwide.

Barry R. Schneider

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Chemical weapon - Chemical weapons and terrorism

# data[].attributes.attachment_link.description
Chemical weapon - Chemical weapons and terrorism: Until the 1990s, terrorists had rarely possessed or employed chemical weapons. However, several states that have sponsored terrorism have also possessed chemical weapons-Libya, Iran, and Iraq-and there is a concern that they and groups they sponsor might use chemical weapons in the future.

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Signed at Geneva, June 17, 1925
Entered Into Force February 8, 1928

At the end of World War I, the victorious Allies decided to reaffirm in the Versailles Treaty (1919) the prewar prohibition of the use of poisonous gases (see Introduction) and to forbid Germany to manufacture or import them. Similar provisions were included in the peace treaties with Austria, Bulgaria, and Hungary.

Drawing upon the language of these peace treaties, the United States -- at the Washington Disarmament Conference of 1922 -- took the initiative of introducing a similar provision into a treaty on submarines and noxious gases. The U.S. Senate gave its advice and consent to ratification of this treaty without a dissenting vote. It never entered into force, however, since French ratification was necessary, and France objected to the submarine provisions.

At the 1925 Geneva Conference for the Supervision of the International Traffic in Arms, the United States similarly took the initiative of seeking to prohibit the export of gases for use in war. At French suggestion it was decided to draw up a protocol on non-use of poisonous gases and at the suggestion of Poland the prohibition was extended to bacteriological weapons. Signed on June 17, 1925, the Geneva Protocol thus restated the prohibition previously laid down by the Versailles and Washington treaties and added a ban on bacteriological warfare.

Before World War II the protocol was ratified by many countries, including all the great powers except the United States and Japan. When they ratified or acceded to the protocol, some nations -- including the United Kingdom, France, and the USSR -- declared that it would cease to be binding on them if their enemies, or the allies of their enemies, failed to respect the prohibitions of the protocol. Although Italy was a party to the protocol, it used poison gas in the Ethiopian war. Nevertheless, the protocol was generally observed in World War II. Referring to reports that the Axis powers were considering the use of gas, President Roosevelt said on June 8, 1943:

Use of such weapons has been outlawed by the general opinion of civilized mankind.

This country has not used them, and I hope that we never will be compelled to use them. I state categorically that we shall under no circumstances resort to the use of such weapons unless they are first used by our enemies.

Although the Senate Foreign Relations Committee favorably reported the protocol in 1926, there was strong lobbying against it, and the Senate never voted on it. After the war, President Truman withdrew it from the Senate, together with other inactive older treaties. Little attention was paid to the protocol for several years thereafter. During the Korean war the Communist side accused the United States of using bacteriological weapons in Korea, but at the same time they rejected American proposals for international investigation of their charges. In the Security Council, the Soviet Union introduced a draft resolution calling on all U.N. members to ratify the protocol. At that time the United States was not willing to agree to prohibit the use of any weapons of mass destruction unless they could be eliminated through a disarmament agreement with effective safeguards. On June 26, 1952, the Soviet resolution was rejected by a vote of 1 to 0, with 10 abstentions (including the United States, the United Kingdom, and France).

In 1966 the Communist countries strongly criticized the United States for using tear gas and chemical herbicides in Vietnam. In the General Assembly, Hungary charged that the use in war of these agents was prohibited by the Geneva Protocol and other provisions of international law. The United States denied that the protocol applied to nontoxic gases or chemical herbicides. Joined by Canada, Italy, and the United Kingdom, the United States introduced amendments to a Hungarian resolution that would have made the use of any chemical and bacteriological weapons an international crime. In its final form the resolution called for "strict observance by all states of the principles and objectives" of the protocol, condemned "all actions contrary to those objectives," and invited all states to accede to the protocol. During the debate the U.S. Representa-tive stated that it would be up to each country to decide whether or how to adhere to the protocol, "in the light of constitutional and other consider-ations."

Interpretation of the protocol remained a thorny problem. In his foreword to a U.N. report on chemical and biological weapons (July 1, 1969), Secretary General Thant recommended a renewed appeal for accession to the protocol and a "clear affirmation" that it covered the use in war of all chemical and biological weapons, including tear gas and other harassing agents. Discussion in the Conference of the Committee on Disarmament (CCD) showed that most members agreed with the Thant recommendations. Swedish Ambassador Myrdal, a strong advocate of the broad interpretation, stressed the danger of escalation if nonlethal chemical agents were permitted. She also pointed out that the military use of tear gases should be distinguished from their use for riot control and that there was a similar difference between using herbicides in war and employing them for peaceful purposes. On the other hand, U.K. Disarmament Minister Mulley held that only the parties to the protocol were entitled to say what it meant.

In the General Assembly, the 12 nonaligned members of the CCD, joined by 9 other nations, introduced a resolution condemning as contrary to international law the use in international armed conflict of all chemical and biological agents. Opposing the resolution, the U.S. Representative reaffirmed the American interpretation of the protocol and took the position that it was inappropriate for the General Assembly to interpret treaties by means of a resolution. The 21-nation resolution was adopted on December 16, 1969, by a vote of 80 to 3 (Australia, Portugal, the United States), and 36 abstentions (including France and the United Kingdom). France and many other abstainers accepted the broad interpretation of the protocol but considered the resolution undesirable on other grounds.

While the General Assembly debate was still underway, President Nixon announced on November 25,1969, that he would resubmit the protocol to the Senate. He reaffirmed U.S. renunciation of the first use of lethal chemical weapons and extended this renunciation to incapacitating chemicals. It was on this occasion that he also announced the unilateral U.S. renunciation of bacteriological (biological) methods of warfare.

Some support for the American interpretation of the protocol now came from the United Kingdom and Japan. During the 1930 discussion at Geneva in the Preparatory Commission for the Disarmament Conference, the United Kingdom had taken the position that the protocol covered tear gas. In February 1970 the British Foreign Secretary told Parliament that this was still the British position, but that the riot-control agent CS, unlike older tear gases, was not harmful to man and was therefore not covered by the protocol. During the Diet debate on Japanese ratification of the protocol, Foreign Minister Aichi took the position that it did not prohibit riot-control agents and herbicides. Japan ratified the protocol in May 1970.

In a report of August 11, 1970, to the President, Secretary of State Rogers recommended that the protocol be ratified with a reservation of the right to retaliate with gas if an enemy state or its allies violated the protocol. He also reaffirmed the position that the protocol did not apply to the use in war of riot-control agents and herbicides. President Nixon resubmitted the protocol to the Senate on August 19.

The Foreign Relations Committee did not accept the Administrations interpretation regarding riot-control agents and herbicides. In a letter of April 15, 1971, to the President, Chairman Fulbright said many members thought that it would be in the interest of the United States either to ratify the protocol without "restrictive understandings" or to postpone action until this became possible. The Committee thus deferred action. It also held in abeyance the Biological Weapons Convention, which was submitted to it on August 10,1972, pending resolution of this issue.

In the latter part of 1974, the Ford Administration launched a new initiative to obtain Senate consent to ratification of the protocol (and simultaneously of the Biological Weapons Convention). The new approach was set forth to the Committee by ACDA Director Fred Ikle on December 10, when he announced that the President, while reaffirming the Administrations view as to the scope of the protocol, was prepared "to renounce as a matter of national policy: (1) first use of herbicides in war except use, under regulations applicable to their domestic use, for control of vegetation within U.S. bases and installations or around their immediate defensive perimeters; (2) first use of riot-control agents in war except in defensive military modes to save lives such as:

(a) Use of riot-control agents in riot-control circumstances to include controlling rioting prisoners of war. This exception would permit use of riot-control agents in riot situations in areas under direct and distinct U.S. military control;

(b) Use of riot-control agents in situations where civilian casualties can be reduced or avoided. This use would be restricted to situations in which civilians are used to mask or screen attacks;

(c) Use of riot-control agents in rescue missions. The use of riot-control agents would be permissible in the recovery of remotely isolated personnel such as downed aircrews (and passengers);

(d) Use of riot-control agents in rear echelon areas outside the combat zone to protect convoys from civil disturbances, terrorists and paramilitary organizations."

In addition, Dr. Ikle testified that "the President, under an earlier directive still in force, must approve in advance any use of riot-control agents and chemical herbicides in war."

Two days later, on December 12, the Committee voted unanimously to send the protocol and the convention to the Senate floor and on December 16 the Senate voted its approval, also unanimously. The Committee, in recommending advice and consent to ratification of the protocol, indicated that it attached particular importance to Dr. Ikles response to the following question posed in connection with his December 10 testimony:

Question: "Assuming the Senate were to give its advice and consent to ratification on the grounds proposed by the Administration, what legal impediment would there be to subsequent Presidential decisions broadening the permissible uses of herbicides and riot-control agents?

Answer: "There would be no formal legal impediment to such a decision. However, the policy which was presented to the Committee will be inextricably linked with the history of Senate consent to ratification of the Protocol with its consent dependent upon its observance. If a future administration should change this policy without Senate consent whether in practice or by a formal policy change, it would be inconsistent with the history of the ratification, and could have extremely grave political repercussions and as a result is extremely unlikely to happen."

The protocol and the convention were ratified by President Ford on January 22, 1975. The U.S. instrument of ratification of the convention was deposited on March 26, 1975, and of the protocol on April 10, 1975.

Responding to the extensive use of chemical weapons between belligerents in the Iran-lraq war and the increasing number of chemical weapon-capable states, President Reagan, in an address to the U.N. General Assembly on September 26, 1988, urged the Parties to the Protocol and all other concerned states to convene a conference to review the rapid deterioration of respect for international norms against chemical weapon use. Hosted by France, 149 states met in Paris, January 7-11, 1989, for a Conference on Chemical Weapons Use. In the Final Declaration, the states "solemnly affirm their commitments not to use chemical weapons and condemn such use." Among other things, they also recognized the importance of the Geneva Protocol, reaffirmed the prohibitions as established in it, and called upon all states which have not yet done so to accede to the Protocol.
Treaty Text Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous or Other Gases, and of Bacteriological Methods of Warfare Signed at Geneva June 17, 1925
Entered into force February 8, 1928
Ratification advised by the U.S. Senate December 16, 1974
Ratified by U.S. President January 22, 1975
U.S. ratification deposited with the
Government of France April 10, 1975
Proclaimed by U.S. President April 29, 1975
The Undersigned Plenipotentiaries, in the name of their respective Governments:

Whereas the use in war of asphyxiating, poisonous or other gases, and of all analogous liquids, materials or devices, has been justly condemned by the general opinion of the civilized world; and

Whereas the prohibition of such use has been declared in Treaties to which the majority of Powers of the World are Parties; and

To the end that this prohibition shall be universally accepted as a part of International Law, binding alike the conscience and the practice of nations;

Declare:

That the High Contracting Parties, so far as they are not already Parties to Treaties prohibiting such use, accept this prohibition, agree to extend this prohibition to the use of bacteriological methods of warfare and agree to be bound as between themselves according to the terms of this declaration.

The High Contracting Parties will exert every effort to induce other States to accede to the present Protocol. Such accession will be notified to the Government of the French Republic, and by the latter to all signatory and acceding Powers, and will take effect on the date of the notification by the Government of the French Republic.

The present Protocol, of which the French and English texts are both authentic, shall be ratified as soon as possible. It shall bear todays date.

The ratifications of the present Protocol shall be addressed to the Government of the French Republic, which will at once notify the deposit of such ratification to each of the signatory and acceding Powers.

The instruments of ratification of and accession to the present Protocol will remain deposited in the archives of the Government of the French Republic.

The present Protocol will come into force for each signatory Power as from the date of deposit of its ratification, and, from that moment, each Power will be bound as regards other powers which have already deposited their ratifications.

IN WITNESS WHEREOF the Plenipotentiaries have signed the present Protocol.

DONE at Geneva in a single copy, this seventeenth day of June, One Thousand Nine Hundred and Twenty-Five.
State Parties Done at Geneva, June 17, 1925
Entered Into Force February 8, 1928*
A = Accession
R = Ratification
D = Declaration of Succession

* This table was formulated using the instruments deposited in the archives of the Government of the French Republic.
Notes

1. In a communication dated July 12, 1996, South Africa withdrew the reservations made at the time of its accession (notification by the French Government upon directive dated October 20, 1966).

2. In a communication dated November 25, 1986, Australia withdrew the reservation it had made on May 24, 1930 (notification by the French Government on December 9, 1986).

3. In a communication dated February 17, 1997, Belgium withdrew the reservations made at the time of its ratification (notification by the French Government upon directive dated February 27, 1997).

4. Bulgaria withdrew the reservation it had made at the time of its ratification of the Protocol on March 7, 1934 (communication by Bulgarian Government dated October 2, 1991, notification of which was given by the French Government on October 15, 1991).

5. In a note verbale dated September 30, 1993, the Ministry of Foreign Affairs and International Cooperation of Cambodia indicated that the Government of the Kingdom of Cambodia considers itself bound by the June 17, 1925 Protocol, to which the Coalition Government of Democratic Cambodia had acceded on March 15, 1983. This 1983 accession had been considered invalid by Australia, Bulgaria, Cuba, Czechoslovakia, Ethiopia, France, the German Democratic Republic, Hungary, Mauritius, Mongolia, Poland, the Soviet Union, and Vietnam.

6. In a communication dated August 20, 1991, Canada withdrew the reservations to the Protocol with respect to bacteriological methods (notification by the French Government on September 6, 1991). In a communication dated October 28, 1999, Canada withdrew the reservations it had made at the time of its ratification of the Protocol (notification by the French Government on November 2, 1999).

7. In a communication dated September 11, 1991, Chile withdrew the reservation it had made at the time of its ratification of the Protocol (notification by the French Government on October 15, 1991).

8. The People's Republic of China acceded to the Protocol by means of a declaration of succession on July 13, 1952.

9. In a communication dated November 27, 1992, Spain withdrew the reservation it had made at the time of its ratification (notification by the French Government on December 28, 1992).

10. In a communication received by the Embassy of France in Talinn on May 28, 1999, Estonia withdrew the reservations it had made at the time of its ratification (notification by the French Government on July 29, 1999).

11. In a declaration dated November 25, 1996, France withdrew its reservations (notification by the French Government upon directive dated December 12, 1996).

12. In a communication dated February 10, 1972, Ireland withdrew the reservation it had made at the time of its accession (notification by the French Government dated May 25, 1972).

13. In a communication dated May 15, 1990, Mongolia withdrew the reservation it had made at the time of its accession (notification by the French Government dated July 10, 1990).

14. Nicaragua ratified the Protocol on September 7, 1990. Instrument received by the French Government on October 5, 1990; notification on October 5, 1990.

15. In a communication dated January 6, 1989, New Zealand withdrew the reservations it had made at the time of its accession (notification by the French Government on May 20, 1989).

16. Panama ratified its accession on March 15, 1971.

17. Notification formalized on January 13, 1969.

18. (a) Includes the Netherlands Antilles, Surinam, and Curaçao.
(b) In a communication received on July 17, 1995, the Netherlands withdrew their reservations made at the time of ratification (notification by the French Government on July 23, 1991).

19. In a communication dated July 16, 1991, Romania withdrew the reservations it had made at the time of its ratification of the Protocol (notification by the French Government on July 23, 1991).

20. (a) In a communication dated November 8, 1991, the United Kingdom withdrew Part 2 of the reservation it had made at the time of its ratification of the Protocol, which Part stated: "The said Protocol shall cease to be binding on His Britannic Majesty towards any Power at enmity with Him whose armed forces, or the armed forces of whose allies, fail to respect the prohibitions laid down in the Protocol." It withdrew Part 2 insofar as it concerns the use of agents, toxins, weapons, equipment, and means of delivery specified in Article 1 of the Convention on the Prohibition of the Development, Production, and Stockpiling of Bacteriological (Biological) and Toxin Weapons and on Their Destruction, of April 10, 1972. (b) In a communication dated June 24, 1997, the United Kingdom indicated that it ceased: "to be responsible for the rights and obligations arising from the application of the Protocol to Hong Kong" (notification by the French Government on July 2, 1997)

21. In a communication dated January 18, 2001, the Russian Federation withdrew the reservations that had been made on April 5, 1928, by the Soviet Union at the time of its ratification of the Protocol (notification by the French Government upon directive dated January 22, 2001).

22. The Czech and Slovak Federal Republic withdrew the reservation it had made at the time of its ratification of the Protocol on August 16, 1938 (communication from the Government of the Czech and Slovak Federal Republic dated September 25, 1990, with notification by the French Government on November 8, 1990.)

23. Slovakia indicated on September 22, 1993, that it considers itself bound by the Protocol and it confirmed this in a communication dated July 1, 1997 (notification by the French Government on July 2, 1997).

24. On March 11,1971, the Yemen Arab Republic deposited its instrument of accession. On September 16, 1973, it sent the French Government a new instrument of accession that includes a reservation. The People's Democratic Republic of Yemen acceded on October 20, 1986.

Current as of September 25, 2002

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Signed at Geneva, June 17, 1925 Entered Into Force February 8, 1928 At the end of World War I, the victorious Allies decided to reaffirm in the Versailles Treaty (1919) the prewar prohibition of the use of poisonous gases (see Introduction) and to forbid Germany to manufacture or import them.

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The World’s Most Dangerous Bioweapons: Threats and Security

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Explore the world’s most dangerous bioweapons and their potential for devastation. From anthrax to smallpox, uncover deadliest biological Agent

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Biological agents are organisms or toxins that can kill or incapacitate people, livestock and crops. A biological attack is the deliberate release of germs or other biological substances that can make you sick.There are three basic groups of biological agents that could likely be used as weapons: bacteria, viruses and toxins.

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The Biological Weapons Convention

Convention on the Prohibition of the Development, Production and Stockpiling of Bacteriological (Biological) and Toxin Weapons and on their Destruction

The Biological Weapons Convention (BWC), the first multilateral disarmament treaty banning the development, production and stockpiling of an entire category of weapons of mass destruction, was opened for signature on 10 April 1972. The BWC entered into force on 26 March 1975.

The Second Review Conference (1986) agreed that the States Parties were to implement a number of confidence-building measures (CBM) in order to prevent or reduce the occurrence of ambiguities, doubts and suspicions and in order to improve international co-operation in the field of peaceful biological activities. The CBMs were expanded by the Third Review Conference (1991).

Under these agreements, the States Parties undertook to provided annual reports - using agreed forms - on specific activities related to the BWC including: data on research centres and laboratories; information on vaccine production facilities; information on national biological defence research and development programmes; declaration of past activities in offensive and/or defensive biological research and development programmes; information on outbreaks of infectious diseases and similar occurrences caused by toxins; publication of results and promotion of use of knowledge and contacts; information on legislation, regulations and other measures.

Recognizing the need to further strengthen the BWC, a group of governmental experts (VEREX) was established at the Third Review Conference (1991) to identify and examine potential verification measures from a scientific and technical standpoint. At a Special Conference in September 1994, the States parties agreed to establish the Ad Hoc Group of the States parties to the BWC in order to negotiate and develop a legally-binding verification regime for the Convention.

The Fourth Review Conference (1996) welcomed the decision of the Ad Hoc Group to intensify its work with a view to completing it before the Fifth Review Conference to be held in 2001. The Ad Hoc Group was unable to conclude the negotiations on the draft legal instrument (protocol).

Due to persisting divergent views and positions on certain key issues, the Fifth Review Conference (2001) decided to adjourn its proceedings and resume its work in November 2002 in Geneva. The Conference was reconvened in November 2002 and adopted a Final Report that included a decision to hold annual meetings of States parties and experts meetings in the next three years leading up to the Review Conference in 2006.

The Sixth Review Conference (2006) succeeded in comprehensively reviewing the Convention, adopting a final document by consensus. The States parties adopted a detailed plan for promoting universal adherence, and decided to update and streamline the procedures for submission and distribution of the Confidence-Building Measures (CBMs). They also adopted a comprehensive intersessional programme spanning from 2007 to 2010. In a significant development, the Conference agreed to establish an Implementation Support Unit (ISU) to assist States parties in implementing the Convention.

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The Biological Weapons Convention (BWC), the first multilateral disarmament treaty banning the development, production and stockpiling of an entire category of weapons of mass destruction, was opened for signature on 10 April 1972. The BWC entered into force on 26 March 1975.

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It is an axiom of human history that whatever technology is available will be applied in warfare as one side or the other seeks to gain an advantage. Humans are unique among the species in their capacity for fighting prolonged conflicts where the nature of the war reflects the types of technologies available. Stone, metal, leather, wood, domesticated animals, wheels, etc. were each exploited by ancient societies in warfare. In late antiquity the adoption of the stirrup in Western Europe transformed warfare by enhancing the fighting capacity of the mounted warrior, which eventually led to the emergence and prominence of the knightly class. More recently gunpowder, steam engines, aircraft, chemicals, electronics and nuclear physics were employed in warfare. In each epoch, the technologies available had enormous influence on the strategy and tactics used. Biological warfare is ancient but its applicability to the battlefield has been limited by its unpredictability, blowback possibility and uncertain efficacy. However, the biological revolution that began in the mid‐20th century has led to the development of powerful technologies that could potentially be used to generate new biological weapons of tremendous destructive power. Although biological warfare is currently prohibited by the 1972 Biological and Toxic Weapons Convention (BTWC) a review of prior attempts to limit the use of certain weapons such as the medieval crossbow, and more recently gas warfare, provides little encouragement for the notion that a technology that is useful in war can be limited by treaty. Furthermore, the BTWC restrictions apply only to signatory nation states and are irrelevant to terrorist organizations or lone wolves type of terrorists. Given the human track record for conflict and the potential power of biological warfare we are led to the sad conclusion that biological warfare has a future, and that society must prepare for the eventuality that it will used again by either nations or individuals. In this essay I will try to peek into the far horizon to identify some general themes that might be helpful in protecting against future horrors fully aware that the nature of technological change is so rapid and profound that any such view must necessarily be myopic.

Existential threats to humanity

In considering the importance of biological warfare as a subject for concern it is worthwhile to review the known existential threats. At this time this writer can identify at three major existential threats to humanity: (i) large‐scale thermonuclear war followed by a nuclear winter, (ii) a planet killing asteroid impact and (iii) infectious disease. To this trio might be added climate change making the planet uninhabitable. Of the three existential threats the first is deduced from the inferred cataclysmic effects of nuclear war. For the second there is geological evidence for the association of asteroid impacts with massive extinction ( Alvarez, 1987). As to an existential threat from microbes recent decades have provided unequivocal evidence for the ability of certain pathogens to cause the extinction of entire species. Although infectious disease has traditionally not been associated with extinction this view has changed by the finding that a single chytrid fungus was responsible for the extinction of numerous amphibian species ( Daszak et al., 1999; Mendelson et al., 2006). Previously, the view that infectious diseases were not a cause of extinction was predicated on the notion that many pathogens required their hosts and that some proportion of the host population was naturally resistant. However, that calculation does not apply to microbes that are acquired directly from the environment and have no need for a host, such as the majority of fungal pathogens. For those types of host-microbe interactions it is possible for the pathogen to kill off every last member of a species without harm to itself, since it would return to its natural habitat upon killing its last host. Hence, from the viewpoint of existential threats environmental microbes could potentially pose a much greater threat to humanity than the known pathogenic microbes, which number somewhere near 1500 species ( Cleaveland et al., 2001; Taylor et al., 2001), especially if some of these species acquired the capacity for pathogenicity as a consequence of natural evolution or bioengineering.

The universe of threats

The universe of threats can potentially encompass all microbes that inhabit the planet. Although most authorities divide microbes into those that are pathogenic and non‐pathogenic there is a fundamental fallacy in assigning the property of pathogenicity to a microbe alone, for virulence is a microbial property that is expressed only in a susceptible host ( Casadevall and Pirofski, 2001). For example, highly virulent microbes such as variola major virus are not virulent in hosts immunized with vaccinia. On the other hand, microbes normally avirulent for immunologically competent hosts such as Aspergillus spp. can be highly pathogenic for hosts with impaired immunity. The fact that virulence is expressed only in a susceptible host implies that it is not an independent microbial property. This is an important concept for it makes it difficult to unequivocally exclude any particular microbe as a potential threat.

Given the enormous microbial diversity in the planet it is remarkable that there are relative few microbes capable of causing human disease. This paucity presumably reflects the effectiveness of vertebrate immunity combined with high temperatures that exclude the overwhelming majority of environmental microbes ( Casadevall and Pirofski, 2007; Robert and Casadevall, 2009). Pathogenic microbes can be divided into two general groups, those acquired from other host and those acquired from the environment. Pathogenic microbes acquired from other hosts tend to be host adapted, are relatively few in number, and include most of the well‐known pathogens. Host‐acquired pathogenic microbes are usually communicable and have historically been responsible for devastating epidemics. In contrast, pathogenic microbes acquired directly from the environment represent a completely different challenge for the host since these have acquired their capacity for pathogenicity by virtue of non‐mammalian selection pressures, such as the interaction with amoebae ( Casadevall and Pirofski, 2007).

Among environmental microbes the major threats to humans come from those microbes that can survive mammalian temperatures. Although the elevated temperatures of mammals almost certainly create a thermal exclusionary environment for a large percentage of environmental microbes, one cannot automatically dismiss microbes that are not thermal tolerant. In this regard it is noteworthy that it was possible to adapt an insect pathogenic fungus to tolerate mammalian temperatures by simple thermal selection in the laboratory ( de Crecy et al., 2009). Whether this adaptation conferred the capacity for mammalian virulence is unknown but the example provides a precedent for the notion that it may be possible to greatly enlarge the number of microbes with human pathogenic capacity by simple selection for more thermally stable variants.

If the universe of threats from the natural world was not enough humanity also faces potential threats from synthetic biology ( Tucker and Zilinkas, 2006; Tucker, 2011). Although the risk of generating Frankenstein microbes accidentally from synthetic biology is quite low, it is not zero. Given sufficient time, experimentation and selection it is possible that technologies emerging from synthetic biology‐related research can find applications in biological warfare.

Preparing against the known and unknown

Despite a universe of threats that is overwhelming with regards to the number of microbes with pathogenic potential current biodefence efforts remain focused on a tiny proportion of biological threats. In fact, governments have responded to the threat of bioterrorism by the creation of lists that aim to protect society by restricting access to certain microbes and toxins and creating legal tools for the prosecution of individuals on the basis of possession alone ( Casadevall and Relman, 2010). Furthermore, such lists have been used to prioritize the development of countermeasures such as increased vigilance, detection devices, diagnostics, vaccines, drugs and therapeutic immunoglobulins. In general, microbial threat lists have been designed by creating algorithms that attempt to identify the most dangerous types of microbes. Although such algorithms are not in the public domain some hint of the types of considerations taken into account in the generation of such lists can be found in an article authored by scientists from the Center of Diseases of Control (Atlanta, GA) ( Rotz et al., 2002), the institution responsible for the administering the Select Agent and toxins regulations. It is noteworthy that their risk matrix analysis for assessing the public health impact of potential biological terrorism agents included such diverse criteria as mortality, need for hospitalization, likelihood for dissemination, availability of countermeasures and public perception ( Rotz et al., 2002). The last parameter is interesting since public recognition of a known danger such as anthrax spores is far more likely to cause panic and societal disruption than less well‐known threats.

A fundamental problem with any microbial threat list is that it is necessarily a backward looking document. History consistently shows that generals always prepare to fight the last war and biological warfare is probably no exception. In this regard, microbial threat lists are primarily populated with agents that have been investigated by the military for biological warfare use, such as Bacillus anthracis, or have caused terrible epidemics in history, such as variola major and Yersinia pestis. Organisms like fungi that have not been associated with major epidemics tend to be ignored in threat analysis scenarios despite the fact that this kingdom, as a whole, includes many species with high weapon potential ( Casadevall and Pirofski, 2006) and the fact that fungal diseases are currently decimating certain amphibian and bat populations. Moreover, recent decades have seen the emergence of numerous new microbial diseases including the human immunodeficiency virus (HIV), severe acute respiratory syndrome (SARS) coronavirus, Ebola virus, Legionella spp., etc. At least 335 new infectious diseases have been described since 1940, with the majority being zoonosis ( Jones et al., 2008). The identification of so many new diseases over the past seven decades shows no sign to slowing, and it is almost a certainty that humanity will continue to confront new microbial threats and that many of these agents, such as SARS coronavirus, possess a significant weapon potential when recovered from nature ( Casadevall and Pirofski, 2004). However, the experience with SARS in 2003 also provides encouragement that even the emergence of a new agent that disseminates rapidly worldwide can be contained. In that outbreak international cooperation combined with good surveillance and a healthy research environment that was able to rapidly identify the agent within weeks of the outbreak, generate diagnostic methods and produce a therapeutic mAb in about 1 year. Consequently biodefence efforts are intimately linked to surveillance efforts for emerging infectious diseases and any defence strategy against biological weapons much consider the development of countermeasures against yet identified threats.

The near and far horizons

The realization that a handful of envelopes containing B. anthracis in 2001 was sufficient to cause widespread panic, and precipitated the first evacuation of the houses of the US government since the war of 1812, provided a clear demonstration of the power of cheap biological weapons. In an age of terrorism biological weapons are perfectly suited for asymmetric warfare where the relatively low costs of producing such weapons combined with their potential for amplification through communicability have a disproportionately strong effect on targeted populations. Consequently, biological weapons are likely to remain very attractive to terrorists and fringe groups like millennial sects. Thus the near horizon is likely to witness continued concern about low intensity use of biological weapons fashioned around known pathogenic microbes such as Salmonella spp. and B. anthracis, which have already been used in terrorism.

The scene on the far horizon is much harder to discern simply because the current rapid the pace of technological advance suggests that new technologies are likely to be developed in coming years that will completely change the landscape for biological warfare offensive and defensive possibilities. Even without envisioning new biological agents, such as those that could be generated by synthetic biology, the technology already exists for significantly enhancing the lethality of biological weapons. The introduction of antimicrobial resistance genes into bacterial agents could significantly enhance their lethality by reducing treatment options. In this regard, it is relatively easy to generate B. anthracis resistant to first line antimicrobial therapies such as ciprofloxacin ( Athamna et al., 2004). The efficacy of vaccines can be circumvented by genetically modifying agents to express immune modifier genes that interfere with the immune response as was demonstrated by the expression of IL‐4 in ectromelia virus ( Jackson et al., 2001). It is noteworthy that microbial modifications to increase lethality is only one possible outcome for engineering biological weapons since these could also be designed to incapacitate instead of kill.

Given the enormous universe of microbial threats, the power of modern biology to enhance the microbial virulence and the high likelihood that biological weapons will continue to threaten humanity one must face the question of how best to protect society. The sheer number of threats and the availability of technologies to modify microbes to defeat available countermeasures suggest that any attempt to achieve defence in depth using microbe‐by‐microbe approaches to biodefence is impractical and ineffective.

A prescription for defence in depth

Continued development of specific diagnostic assays and countermeasures (vaccines, drugs, antibodies) for high risk threats identified by current matrix threat analysis. This is essentially a continuation of the major societal response to perceived biological threats in the first decade of the 21st century when a significant proportion of government supported research has focused on known agents such as variola major, B. anthracis and other high risk agents. This approach makes sense given that known agents will continue to be the most likely threats in the near horizon.

Develop host‐targeted interventions that enhance immune function against a wide variety of threats. In other words, develop therapies that produce temporary increases in immune function that would protect against known and unknown threats. This approach would provide defensive options against yet to be identified microbial threats.

Develop new ways to assess the healthy state that could allow monitoring of the population to identify the appearance of new agents. Although physicians can readily identify the disease state and surveillance systems for known agents are critically important for identifying a biological attack, such approaches may not suffice for all threats. For example, consider the situation with the outbreak of the HIV epidemic. The epidemic was identified in 1981 as a consequence of clusters of cases with known infectious diseases that did not fit known epidemiological parameters for such maladies as they included rare diseases in individuals with no predisposing conditions. However, we now know that AIDS can follow many years after the HIV infection and the interval between infection and disease is characterized by a slow decline in immune function during which the individual does not exhibit signs of disease. Arguably, the existence of methodology that could assess the healthy state might have identified the silent spread of the virus in certain populations years prior to the onset of the epidemic.

Obtain a better understanding of microbial diseases in animal species and especially those that come in close contact with humans. Given that 72% of emergent infectious diseases described in recent decades have been zoonosis ( Jones et al., 2008), it is reasonable to assume that wildlife will continue to be source of new pathogenic microbes for humans and a potential source of biological weapons. Consequently any effort to design a system for defence in depth should include efforts to describe, catalogue and study microbial diseases in wildlife.

In preparing for known and unknown threats the availability of a vigorous scientific research establishment that can respond rapidly is an essential component for any effort to defend society. The rapid identification of HIV as the cause of AIDS and the development of effective anti‐retroviral therapies was made possible by prior societal investments in studying the biology of retroviruses at a time when these were not associated with human diseases. Hence, continued investments in basic research with emphasis on fostering a better understanding of host-microbe interactions is an essential cornerstone for any effort to defend in depth against biological weapons.

References

Athamna A., Athamna M., Abu‐Rashed N., Medlej B., Bast D.J., Rubinstein E. Selection of Bacillus anthracis isolates resistant to antibiotics. J Antimicrob Chemother. 2004;54:424-428. [PubMed]

Mendelson J.R., III, Lips K.R., Gagliardo R.W., Rabb G.B., Collins J.P., Diffendorfer J.E. Biodiversity. Confronting amphibian declines and extinctions. et al. [PubMed]

Tucker J.B. Could terrorist exploit synthetic biology? New Atlantis. 2011;31:69-81.

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It is an axiom of human history that whatever technology is available will be applied in warfare as one side or the other seeks to gain an advantage. Humans are unique among the species in their capacity for fighting prolonged conflicts where the nature of the war reflects the types of technologies available.

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"Biological weapons." The phrase alone could send chills down the spine. But what are they? How do they work? And are we really at risk? In this Spotlight, we survey their history and potential future.

Biological warfare has been used for thousands of years.

Sometimes known as "germ warfare," biological weapons involve the use of toxins or infectious agents that are biological in origin. This can include bacteria, viruses, or fungi.

These agents are used to incapacitate or kill humans, animals, or plants as part of a war effort.

In effect, biological warfare is using non-human life to disrupt - or end - human life. Because living organisms can be unpredictable and incredibly resilient, biological weapons are difficult to control, potentially devastating on a global scale, and prohibited globally under numerous treaties.

Of course, treaties and international laws are one thing - and humanity's ability to find innovative ways of killing each other is another.

Biological warfare: The early days

The history of biological warfare is a long one, which makes sense; its deployment can be a lo-fi affair, so there is no need for electrical components, nuclear fusion, or rocket grade titanium, for instance.

An early example takes us back more than 2 and a half millennia: Assyrians infected their enemy's wells with a rye ergot fungus, which contains chemicals related to LSD. Consuming the tainted water produced a confused mental state, hallucinations, and, in some cases, death.

In the 1300s, Tartar (Mongol) warriors besieged the Crimean city of Kaffa. During the siege, many Tartars died at the hands of plague, and their lifeless, infected bodies were hurled over the city walls.

Some researchers believe that this tactic may have been responsible for the spread of Black Death plague into Europe. If so, this early use of biological warfare caused the eventual deaths of around 25 million Europeans.
This is a prime example of biological warfare's potential scope, unpredictability, and terrifying simplicity.
Moving forward to 1763, the British Army attmped to use smallpox as a weapon against Native Americans at the Siege of Fort Pitt. In an attempt to spread the disease to the locals, the Brits presented blankets from a smallpox hospital as gifts.

Although we now know that this would be a relatively ineffective way to transmit smallpox, the intent was there.

During World War II, many of the parties involved looked into biological warfare with great interest. The Allies built facilities capable of mass producing anthrax spores, brucellosis, and botulism toxins. Thankfully, the war ended before they were used.

It was the Japanese who made the most use of biological weapons during World War II, as among other terrifyingly indiscriminate attacks, the Japanese Army Air Force dropped ceramic bombs full of fleas carrying the bubonic plague on Ningbo, China.

The following quote comes from a paper on the history of biological warfare.

"[T]he Japanese army poisoned more than 1,000 water wells in Chinese villages to study cholera and typhus outbreaks. [...] Some of the epidemics they caused persisted for years and continued to kill more than 30,000 people in 1947, long after the Japanese had surrendered."

Dr. Friedrich Frischknecht, professor of integrative parasitology, Heidelberg University, Germany

Bioterrorism: Modern concerns

The Centers for Disease Control and Prevention (CDC) define bioterrorism as "the intentional release of viruses, bacteria, or other germs that can sicken or kill people, livestock, or crops."

How likely is a bioterrorism attack today?

This can be achieved in a number of ways, such as: via aerosol sprays; in explosive devices; via food or water; or absorbed or injected into skin.

Because some pathogens are less robust than others, the type of pathogen used will define how it can be deployed.

Utilizing such weapons holds a certain appeal to terrorists; they have the potential to cause great harm, of course, but they are also fairly cheap to produce when compared with missiles or other more hi-tech equipment.

Also, they can be "detonated," and, due to the long time that it takes for them to spread and take effect, there is plenty of time for the perpetrator to escape undetected.

Biological weapons can be difficult to control or predict in a battlefield situation, since there is a substantial risk that troops on both sides will be affected. However, if a terrorist is interested in attacking a distant target as a lone operant, bioterrorism carries much less risk to the person.

Anthrax

Experts believe that today, the most likely organism to be used in a bioterrorism attack would be Bacillus anthracis, the bacteria that causes anthrax.

It is widely found in nature, easily produced in the laboratory, and survives for a long time in the environment. Also, it is versatile and can be released in powders, sprays, water, or food.

Anthrax has been used before. In 2001, anthrax spores were sent through the United States postal system. In all, 22 people contracted anthrax - five of whom died. And, the guilty party was never caught.

Smallpox

Another potential agent of bioterrorism is smallpox, which, unlike anthrax, can spread from person to person. Smallpox is no longer a disease of concern in the natural world - because concerted vaccination efforts stamped it out - and the last naturally spread case occurred in 1977.

However, if someone were to gain access to the smallpox virus (it is still kept in two laboratories - one in the U.S. and one in Russia), it could be an effective weapon, spreading quickly and easily between people.

Plague

We have already mentioned the Tartars' use of the plague, Yersinia pestis, hundreds of years ago, but some believe that it could be used in the modern world, too. Y. pestis is passed to humans through the bite of a flea that has fed on infected rodents.

Once a human is infected, the resulting disease can either develop into bubonic plague, which is difficult to transmit among humans and fairly easy to treat with antibiotics, or - if the infection spreads to the lungs - it becomes pneumonic plague, which develops rapidly and does not respond well to antibiotics.

A paper written on the plague and its potential for use in biological terrorism says:

"Given the presence and availability of plague around the world, the capacity for mass production and aerosol dissemination, the high fatality rate of pneumonic plague, and the potential for rapid secondary spread, the potential use of plague as a biological weapon is of great concern."

Dr. Stefan Riedel, Department of Pathology, Baylor University Medical Center, Dallas, TX

Cholera

As a potentially severe and sometimes deadly gastrointestinal disease, cholera has the potential to be used in bioterrorism. It does not spread easily from person to person, so for it to be effective, it would need to be liberally added to a major water source.

In the past, the bacteria responsible for cholera, Vibrio cholerae, has been weaponized by the U.S., Japan, South Africa, and Iraq, among others.

Tularemia

Some consider tularemia, an infection caused by the Francisella tularensis bacterium, as a potential bioweapon. It causes fever, ulcerations, swelling of lymph glands, and, sometimes, pneumonia.

The bacterium can cause infection by entering through breaks in the skin or by being breathed into the lungs. It is particularly infectious, and only a very small number of organisms (as few as 10) need to enter the body to set off a serious bout of tularemia.

Studied by the Japanese during World War II and stockpiled by the U.S. in the 1960s, F. tularensis is hardy, capable of withstanding low temperatures in water, hay, decaying carcasses, and moist soil for many weeks.
According to the Johns Hopkins Center for Public Health Preparedness, "Aerosol dissemination of F. tularensis in a populated area would be expected to result in the abrupt onset of large numbers of cases of acute, non-specific, febrile illness beginning 3 to 5 days later [...], with pleuropneumonitis developing in a significant proportion of cases."
"Without antibiotic treatment, the clinical course could progress to respiratory failure, shock, and death."

Those pathogens are an abbreviated selection, of course. Others considered to have potential as biological weapons include brucellosis, Q fever, monkeypox, arboviral encephalitides, viral hemorrhagic fevers, and staphylococcal enterotoxin B.

A worrying future?

Although biological weapons are as old as the hills (if not older), modern technology brings new worries. Some experts are concerned about recent advances in gene editing technology.

Could gene editing become the bioterrorist's tool of choice?

When utilized for good, the latest tools can work wonders. However - as with most cutting-edge technology - there is always the potential for misuse.

A gene editing technology called CRISPR has set off alarm bells in the defense community; the technology allows researchers to edit genomes, thereby easily modifying DNA sequences to alter gene function.

In the right hands, this tool has the potential to correct genetic defects and treat disease. In the wrong hands, however, it has the potential for evil.

CRISPR technology is becoming cheaper to run and therefore more accessible to individuals bent on bioterrorism.

A report titled Worldwide Threat Assessment of the U.S. Intelligence Community, written by James Clapper, the director of National Intelligence, was published in February 2016. In it, gene editing features in a list of weapons of mass destruction and proliferation.
"Given the broad distribution, low cost, and accelerated pace of development of this dual-use technology," he explains, "its deliberate or unintentional misuse might lead to far-reaching economic and national security implications."
"Advances in genome editing in 2015," he continues, "have compelled groups of high-profile U.S. and European biologists to question unregulated editing of the human germline (cells that are relevant for reproduction), which might create inheritable genetic changes."

With future generations of CRISPR-like technology and an advanced knowledge of genetics, there would be no theoretical end to the misery that could be caused. There's potential to create drug-resistant strains of diseases, for instance, or pesticide-protected bugs, capable of wiping out a country's staple crop.

For now, however, other methods of bioterrorism are much easier and closer to hand, so this is likely to be of little concern for the foreseeable future.

In fact, to lighten the mood at the end of a somewhat heavy article, just remember that anyone who lives in the U.S. today is much more likely to be killed in an animal attack than a terrorist attack - biological or otherwise.

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Biological weapons and bioterrorism: Past, present, and future

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"Biological weapons." The phrase alone could send chills down the spine. But what are they? How do they work? And are we really at risk? In this Spotlight, we survey their history and potential future. Biological warfare has been used for thousands of years.

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Anthrax is caused by infection with Bacillus anthracis, a hardy, spore-forming bacterium that can survive in extreme conditions for a long time. The bacterium is highly toxic.

Anthrax infection is rare in the United States, but not uncommon elsewhere.

Anthrax is common in livestock, and a potentially serious infectious disease in humans. The spores occur naturally in soil, but anthrax only becomes active when it enters the body.

Bacillus anthracis (B. anthracis) gained notoriety as a biological weapon in the 2001 in the United States (U.S.), when anthrax powder was mailed in packages, leading to 22 cases of infection, including 5 fatalities.

However, the disease is not unusual in the agricultural regions of the Caribbean, central and southwestern Asia, Central and South America, southern and eastern Europe and sub-Saharan Africa. How dangerous it is depends on the type.

It is rare in the U.S., but outbreaks occur very occasionally in grazing animals such as deer. It is more likely in countries that do not routinely vaccinate animals against the disease.

It cannot pass from one human to another.

Fast facts on anthrax:

Here are some key points about anthrax. More detail is in the main article.

Anthrax is a potentially fatal bacterial infection that is rare in the U.S. but more common elsewhere.

There are four types, depending on how it is transmitted.

Anthrax can be spread through animals and animal products.

Treatment is with antibiotics, which must be started soon after infection.

There is a possibility that anthrax could be used as a biological weapon.

A vaccine exists for people who are at risk, but not for the general public.

What is anthrax?

B. anthracis bacteria produce resilient spores that can cause a potentially deadly infection in people and animals.

There are four different forms of anthrax infection:

Each type is caused by the B. anthracis bacteria entering the human body in a different way. Each route of entry leads to a unique set of symptoms.

Causes

Anthrax infection happens when the bacterium B. anthracis enters the body through inhaling, swallowing, injecting, or through skin contact.

Anthrax spores are resistant to many environmental stresses and normally lie dormant. If they enter the body of a person or an animal, they can develop into active growing cells, due to the presence of water, sugars, and other nutrients.

Once active, the bacteria multiply throughout the body, creating toxins that can cause severe illness.

Anthrax consists of three proteins. None of these proteins is toxic on its own, but combined, they can make a lethal mix, disrupting cellular signaling pathways and stopping cells from working properly, shutting down the host's immune system, and leading to death.

The most common form of anthrax, cutaneous anthrax, mostly spreads through contact with contaminated animal products such as hides and hair. People have developed anthrax after using the hides of infected animals to make traditional African drums.

Bioterrorism

If a person deliberately releases a virus or bacteria that can lead to sickness or death, this is known as a biological attack.

Anthrax could be used as a bioterror weapon because it is easy to produce.

According to the Centers for Disease Control and Prevention (CDC), if a biological attack were to occur, the anthrax bacteria is " one of the most likely agents."

There are several reasons for this, for example:

anthrax is easy to find in nature and easy to grow in labs

an attack would be hard to detect

it has previously been used as a weapon

Federal agencies and health departments in the U.S. work together to ensure preparedness for such an event. However, they would not know it had happened until a pattern of infection emerged. This is because it is rare, symptoms take a while to show, and they are also similar to symptoms of other conditions, such as flu.

Symptoms

Each form of anthrax has its own range of symptoms. For most forms, the symptoms appear within a week of exposure to B. anthracis, but the symptoms of inhalation anthrax can take over a month to develop.

Cutaneous anthrax

The most common form of anthrax is cutaneous anthrax.

The symptoms are as follows:

small itchy blisters or bumps

a painless swollen sore with a black center

swelling in nearby lymph glands and tissue

This is considered the mildest form. With treatment, it is rarely deadly. Without treatment, it may be fatal in 20 percent of cases.

Gastrointestinal anthrax

This can come from eating raw or undercooked meat from an infected animal.

The symptoms of gastrointestinal anthrax are:

abdominal pain and swelling

fainting

fever and chills

flushing face and red eyes

loss of appetite

nausea and vomiting

sore throat with painful swallowing

swelling of neck and neck glands

Without treatment, half of patients die, but with treatment, 60 percent will survive.

Inhalation anthrax

The initial symptoms of inhalation anthrax are:

chest discomfort

coughing up blood

nausea and vomiting

pain when swallowing

flu-like symptoms

As the disease progresses, the individual is likely to experience:

This is the most deadly kind of anthrax. Without treatment, it is fatal in 85 to 90 percent of cases.

Injection anthrax

This has affected people who inject heroin in Europe, but it has not been reported in the U.S.

The initial symptoms of injection anthrax are:

abscesses in and around the injection site

blisters and bumps around the injection site

fever

a swollen sore near the injection site

As the disease progresses, the following may develop:

The effects probably depend on how deep they are, but symptoms can also be confused with those of other infections.

Tests and diagnosis

Anthrax shares many symptoms with more common conditions, such as flu and pneumonia. A health care provider will rule these out first before considering anthrax, unless there is a specific reason to suspect it.

If other conditions are ruled out, then tests specific to anthrax may follow.

An anthrax diagnosis can only be confirmed by measuring antibodies or toxins in the blood or other tissue. The type of tissue sample and other types of test will depend on the suspected form of anthrax.

Tests include:

a skin biopsy to test for cutaneous anthrax

stool testing for gastrointestinal anthrax

chest x-rays or CT scans to detect inhalation anthrax

lumbar punctures to reveal anthrax meningitis

In 2014, researchers researchers that a "glow test" can detect the presence of deadly anthrax bacteria in hours instead of days. This could significantly cut the time it takes to respond to a potential bioterrorism attack.

Treatment

Anthrax must be treated as quickly as possible, before the levels of toxins and harmful bacteria within the body become too high for drugs to eliminate.

The standard treatment for anthrax is with antibiotics and antitoxins. The type of antibiotics will depend on how the infection occurred, the individual's age and medical history.

Antitoxin therapies are currently being developed that target the toxins released by B. anthracis, rather than the bacteria themselves.

Recently, surgical removal of infected tissue has been used successfully to treat injection anthrax.

In 2013, a team of researchers discovered a new chemical compound from the sea that could be used to treat anthrax and MRSA.

Prevention

Tips for avoiding anthrax include:

only eating meat that has been suitably slaughtered and cooked

avoiding contact with raw animal hides, especially those of cows, sheep, and goats

People who work with fur, hides, and wool, especially if these are imported, should take extra care.

Anthrax molecules are made up of three proteins, none of which is toxic on its own. It can be present in imported animal products.

If anyone is exposed to the bacteria, antibiotics can prevent the symptoms of anthrax from developing before the B. anthracis spores have time to activate.

The U.S. Food and Drug Administration (FDA) have approved a vaccine for anthrax, to be used prior to exposure by adults who could be at risk.

These include laboratory workers, handlers of animals and animal products, and some military personnel. It is not available to the public.

The vaccine can also be given after exposure, alongside antimicrobial therapy.

Anthrax remains rare in the U.S. If a person has symptoms that resemble anthrax, it is most likely a more common illness.

If a person shows signs and symptoms after exposure to animals or animal products from parts of the world where anthrax is common, however, it is best to contact a health care provider.

To be effective, treatment for anthrax must begin as soon as possible.

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Anthrax is a deadly infection that is rare in the United States but common in animals globally. There are different forms, but all are serious. While focus is often on the use of anthrax for criminal purposes, the bacteria is more likely to spread through contact with or consumption of contaminated meat or hides.

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During the past century, more than 500 million people died of infectious diseases. Several tens of thousands of these deaths were due to the deliberate release of pathogens or toxins, mostly by the Japanese during their attacks on China during the Second World War. Two international treaties outlawed biological weapons in 1925 and 1972, but they have largely failed to stop countries from conducting offensive weapons research and large-scale production of biological weapons. And as our knowledge of the biology of disease-causing agents-viruses, bacteria and toxins-increases, it is legitimate to fear that modified pathogens could constitute devastating agents for biological warfare. To put these future threats into perspective, I discuss in this article the history of biological warfare and terrorism.

During the [Second World War], the Japanese army poisoned more than 1,000 water wells in Chinese villages to study cholera and typhus outbreaks

Man has used poisons for assassination purposes ever since the dawn of civilization, not only against individual enemies but also occasionally against armies (). However, the foundation of microbiology by Louis Pasteur and Robert Koch offered new prospects for those interested in biological weapons because it allowed agents to be chosen and designed on a rational basis. These dangers were soon recognized, and resulted in two international declarations-in 1874 in Brussels and in 1899 in The Hague-that prohibited the use of poisoned weapons. However, although these, as well as later treaties, were all made in good faith, they contained no means of control, and so failed to prevent interested parties from developing and using biological weapons. The German army was the first to use weapons of mass destruction, both biological and chemical, during the First World War, although their attacks with biological weapons were on a rather small scale and were not particularly successful: covert operations using both anthrax and glanders () attempted to infect animals directly or to contaminate animal feed in several of their enemy countries ( Wheelis, 1999). After the war, with no lasting peace established, as well as false and alarming intelligence reports, various European countries instigated their own biological warfare programmes, long before the onset of the Second World War ( Geissler & Moon, 1999).

Table 1

1155

Emperor Barbarossa poisons water wells with human bodies, Tortona, Italy

1346

Mongols catapult bodies of plague victims over the city walls of Caffa, Crimean Peninsula

1495

Spanish mix wine with blood of leprosy patients to sell to their French foes, Naples, Italy

1650

Polish fire saliva from rabid dogs towards their enemies

1675

First deal between German and French forces not to use 'poison bullets'

1763

British distribute blankets from smallpox patients to native Americans

1797

Napoleon floods the plains around Mantua, Italy, to enhance the spread of malaria

1863

Confederates sell clothing from yellow fever and smallpox patients to Union troops, USA

Table 2

In North America, it was not the government but a dedicated individual who initiated a bioweapons research programme. Sir Frederick Banting, the Nobel-Prize-winning discoverer of insulin, created what could be called the first private biological weapon research centre in 1940, with the help of corporate sponsors ( Avery, 1999; Regis, 1999). Soon afterwards, the US government was also pressed to perform such research by their British allies who, along with the French, feared a German attack with biological weapons ( Moon, 1999, Regis, 1999), even though the Nazis apparently never seriously considered using biological weapons ( Geissler, 1999). However, the Japanese embarked on a largescale programme to develop biological weapons during the Second World War ( Harris, 1992, 1999, 2002) and eventually used them in their conquest of China. Indeed, alarm bells should have rung as early as 1939, when the Japanese legally, and then illegally, attempted to obtain yellow fever virus from the Rockefeller Institute in New York ( Harris, 2002).

The father of the Japanese biological weapons programme, the radical nationalist Shiro Ishii, thought that such weapons would constitute formidable tools to further Japan's imperialistic plans. He started his research in 1930 at the Tokyo Army Medical School and later became head of Japan's bioweapon programme during the Second World War ( Harris, 1992, 1999, 2002). At its height, the programme employed more than 5,000 people, and killed as many as 600 prisoners a year in human experiments in just one of its 26 centres. The Japanese tested at least 25 different disease-causing agents on prisoners and unsuspecting civilians. During the war, the Japanese army poisoned more than 1,000 water wells in Chinese villages to study cholera and typhus outbreaks. Japanese planes dropped plague-infested fleas over Chinese cities or distributed them by means of saboteurs in rice fields and along roads. Some of the epidemics they caused persisted for years and continued to kill more than 30,000 people in 1947, long after the Japanese had surrendered ( Harris, 1992, 2002). Ishii's troops also used some of their agents against the Soviet army, but it is unclear as to whether the casualties on both sides were caused by this deliberate spread of disease or by natural infections ( Harris, 1999). After the war, the Soviets convicted some of the Japanese biowarfare researchers for war crimes, but the USA granted freedom to all researchers in exchange for information on their human experiments. In this way, war criminals once more became respected citizens, and some went on to found pharmaceutical companies. Ishii's successor, Masaji Kitano, even published postwar research articles on human experiments, replacing 'human' with 'monkey' when referring to the experiments in wartime China ( Harris, 1992, 2002).

Although some US scientists thought the Japanese information insightful, it is now largely assumed that it was of no real help to the US biological warfare programme projects. These started in 1941 on a small scale, but increased during the war to include more than 5,000 people by 1945. The main effort focused on developing capabilities to counter a Japanese attack with biological weapons, but documents indicate that the US government also discussed the offensive use of anti-crop weapons ( Bernstein, 1987). Soon after the war, the US military started open-air tests, exposing test animals, human volunteers and unsuspecting civilians to both pathogenic and non-pathogenic microbes ( Cole, 1988; Regis, 1999). A release of bacteria from naval vessels off

...nobody really knows what the Russians are working on today and what happened to the weapons they produced

the coasts of Virginia and San Francisco infected many people, including about 800,000 people in the Bay area alone. Bacterial aerosols were released at more than 200 sites, including bus stations and airports. The most infamous test was the 1966 contamination of the New York metro system with Bacillus globigii - a non-infectious bacterium used to simulate the release of anthrax-to study the spread of the pathogen in a big city. But with the opposition to the Vietnam War growing and the realization that biological weapons could soon become the poor man's nuclear bomb, President Nixon decided to abandon offensive biological weapons research and signed the Biological and Toxin Weapons Convention (BTWC) in 1972, an improvement on the 1925 Geneva Protocol. Although the latter disallowed only the use of chemical or biological weapons, the BTWC also prohibits research on biological weapons. However, the BTWC does not include means for verification, and it is somewhat ironic that the US administration let the verification protocol fail in 2002, particularly in view of the Soviet bioweapons project, which not only was a clear breach of the BTWC, but also remained undetected for years.

Even though they had just signed the BTWC, the Soviet Union established Biopreparat, a gigantic biowarfare project that, at its height, employed more than 50,000 people in various research and production centres ( Alibek & Handelman, 1999). The size and scope of the Soviet Union's efforts were truly staggering: they produced and stockpiled tons of anthrax bacilli and smallpox virus, some for use in intercontinental ballistic missiles, and engineered multidrug-resistant bacteria, including plague. They worked on haemorrhagic fever viruses, some of the deadliest pathogens that humankind has encountered. When virologist Nikolai Ustinov died after injecting himself with the deadly Marburg virus, his colleagues, with the mad logic and enthusiasm of bioweapon developers, re-isolated the virus from his body and found that it had mutated into a more virulent form than the one that Ustinov had used. And few took any notice, even when accidents happened. In 1971, smallpox broke out in the Kazakh city of Aralsk and killed three of the ten people that were infected. It is speculated that they were infected from a bioweapons research centre on a small island in the Aral Sea ( Enserink, 2002). In the same area, on other occasions, several fishermen and a researcher died from plague and glanders, respectively ( Miller et al., 2002). In 1979, the Soviet secret police orchestrated a large cover-up to explain an outbreak of anthrax in Sverdlovsk, now Ekaterinburg, Russia, with poisoned meat from anthrax-contaminated animals sold on the black market. It was eventually revealed to have been due to an accident in a bioweapons factory, where a clogged air filter was removed but not replaced between shifts () ( Meselson et al., 1994; Alibek & Handelman, 1999).

The most striking feature of the Soviet programme was that it remained secret for such a long time. During the Second World War, the Soviets used a simple trick to check whether US researchers were occupied with secret research: they monitored whether American physicists were publishing their results. Indeed, they were not, and the conclusion was, correctly, that the US was busy building a nuclear bomb ( Rhodes, 1988, pp. 327 and 501). The same trick could have revealed the Soviet bioweapons programme much earlier (). With the collapse of the Soviet Union, most of these programmes were halted and the research centres abandoned or converted for civilian use. Nevertheless, nobody really knows what the Russians are working on today and what happened to the weapons they produced. Western security experts now fear that some stocks of biological weapons might not have been destroyed and have instead fallen into other hands ( Alibek & Handelman, 1999; Miller et al., 2002). According to US intelligence, South Africa, Israel, Iraq and several other countries have developed or still are developing biological weapons ( Zilinskas, 1997; Leitenberg, 2001).

Apart from state-sponsored biowarfare programmes, individuals and non-governmental groups have also gained access to potentially dangerous microorganisms, and some have used them ( Purver, 2002). A few examples include the spread of hepatitis, parasitic infections, severe diarrhoea and gastroenteritis. The latter occurred when a religious sect tried to poison a whole community by spreading Salmonella in salad bars to interfere with a local election ( Török et al., 1997; Miller et al., 2002). The sect, which ran a hospital on its grounds, obtained the bacterial strain from a commercial supplier. Similarly, a right-wing laboratory technician tried to get hold of the plague bacterium from the American Tissue Culture Collection, and was only discovered after he complained that the procedure took too long ( Cole, 1996). These examples clearly indicate that organized groups or individuals with sufficient determination can obtain dangerous biological agents. All that is required is a request to 'colleagues' at scientific institutions, who share their published materials with the rest of the community ( Breithaupt, 2000). The relative ease with which this can be done explains why the numerous hoaxes in the USA after the anthrax mailings had to be taken seriously, thus causing an estimated economic loss of US $100 million ( Leitenberg, 2001).

These examples clearly indicate that organized groups or individuals with sufficient determination can obtain dangerous biological agents

Another religious cult, in Japan, proved both the ease and the difficulties of using biological weapons. In 1995, the Aum Shinrikyo cult used Sarin gas in the Tokyo subway, killing 12 train passengers and injuring more than 5,000 ( Cole, 1996). Before these attacks, the sect had also tried, on several occasions, to distribute (non-infectious) anthrax within the city with no success. It was obviously easy for the sect members to produce the spores but much harder to disseminate them ( Atlas, 2001; Leitenberg, 2001). The still unidentified culprits of the 2001 anthrax attacks in the USA were more successful, sending contaminated letters that eventually killed five people and, potentially even more seriously, caused an upsurge in demand for antibiotics, resulting in over-use and thus contributing to drug resistance ( Atlas, 2001; Leitenberg, 2001; Miller et al., 2002).

One interesting aspect of biological warfare is the accusations made by the parties involved, either as excuses for their actions or to justify their political

Cuba frequently accused the USA of using biological warfare

goals. Many of these allegations, although later shown to be wrong, have been exploited either as propaganda or as a pretext for war, as recently seen in the case of Iraq. It is clearly essential to draw the line between fiction and reality, particularly if, on the basis of such evidence, politicians call for a 'pre-emptive' war or allocate billions of dollars to research projects. Examples of such incorrect allegations include a British report before the Second World War that German secret agents were experimenting with bacteria in the Paris and London subways, using harmless species to test their dissemination through the transport system ( Regis, 1999; Leitenberg, 2001). Although this claim was never substantiated, it might have had a role in promoting British research on anthrax in Porton Down and on Gruinard Island. During the Korean War, the Chinese, North Koreans and Soviets accused the USA of deploying biological weapons of various kinds. This is now seen as wartime propaganda, but the secret deal between the USA and Japanese bioweapons researchers did not help to diffuse these allegations ( Moon, 1992). Later, the USA accused the Vietnamese of dropping fungal toxins on the US Hmong allies in Laos. However, it was found that the yellow rain associated with the reported variety of syndromes was simply bee faeces (; Seeley et al., 1985). The problem with such allegations is that they develop a life of their own, no matter how unbelievable they are. For example, the conspiracy theory that HIV is a biological weapon is still alive in some people's minds. Depending on whom one asks, KGB or CIA scientists developed HIV to damage the USA or to destabilize Cuba, respectively. Conversely, in 1997, Cuba was the first country to officially file a complaint under Article 5 of the BTWC, accusing the USA of releasing a plant pathogen ( Leitenberg, 2001). Although this was never proven, the USA did indeed look into biological agents to kill Fidel Castro and Frederik Lumumba of the Democratic Republic of Congo ( Miller et al., 2002).

We are witnessing a renewed interest in biological warfare and terrorism owing to several factors, including the discovery that Iraq has been developing biological weapons ( Zilinskas, 1997), several bestselling novels describing biological attacks, and the anthrax letters after the terrorist attacks on 11 September 2001. As history tells us, virtually no nation with the ability to develop weapons of mass destruction has abstained from doing so. And the Soviet project shows that international treaties are basically useless unless an effective verification procedure is in place. Unfortunately, the same knowledge that is needed to develop drugs and vaccines against pathogens has the potential to be abused for the development of biological weapons (; Finkel, 2001). Thus, some critics have suggested that information about potentially harmful pathogens should not be made public but rather put into the hands of 'appropriate representatives' ( Danchin, 2002; Wallerstein, 2002). A recent report on anti-crop agents was already self-censored before publication, and journal editors now recommend special scrutiny for sensitive papers ( Mervis & Stokstad, 2002; Cozzavelli, 2003; Malakoff, 2003). Whether or not such measures are useful deterrents might be questionable, because the application of available knowledge is clearly enough to kill. An opposing view calls for the imperative publication of information about the development of biological weapons to give scientists, politicians and the interested public all the necessary information to determine a potential threat and devise countermeasures.

...virtually no nation with the ability to develop weapons of mass destruction has abstained from doing so

The current debate about biological weapons is certainly important in raising awareness and increasing our preparedness to counter a potential attack. It could also prevent an overreaction such as that caused in response to the anthrax letters mailed in the USA. However, contrasting the speculative nature of biological attacks with the grim reality of the millions of people who still die each year from preventable infections, we might ask ourselves just how many resources we can afford to allocate in preparation for a hypothetical human-inflicted disaster.

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Human experimentation, modern nightmares and lone madmen in the twentieth century

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tear gas

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Section Editor: Jeffrey D. Laskin 1

Abstract

Deployments of tear gas and pepper spray have rapidly increased worldwide. Large amounts of tear gas have been used in densely populated cities, including Cairo, Istanbul, Rio de Janeiro, Manama (Bahrain), and Hong Kong. In the United States, tear gas was used extensively during recent riots in Ferguson, Missouri. Whereas tear gas deployment systems have rapidly improved-with aerial drone systems tested and requested by law enforcement-epidemiological and mechanistic research have lagged behind and have received little attention. Case studies and recent epidemiological studies revealed that tear gas agents can cause lung, cutaneous, and ocular injuries, with individuals affected by chronic morbidities at high risk for complications. Mechanistic studies identified the ion channels TRPV1 and TRPA1 as targets of capsaicin in pepper spray, and of the tear gas agents chloroacetophenone, CS, and CR. TRPV1 and TRPA1 localize to pain‐sensing peripheral sensory neurons and have been linked to acute and chronic pain, cough, asthma, lung injury, dermatitis, itch, and neurodegeneration. In animal models, transient receptor potential inhibitors show promising effects as potential countermeasures against tear gas injuries. On the basis of the available data, a reassessment of the health risks of tear gas exposures in the civilian population is advised, and development of new countermeasures is proposed.

Keywords: tear gas, pepper spray, capsaicin, chlorobenzalmalononitrile, CS, CN, CR, TRPV1, TRPA1

Tear gas agents for riot control

Over the past several decades, tear gas has been used as a common riot‐control agent (RCA) by law enforcement to quell protests, riots, and civil unrest. Tear gas use has dramatically increased in recent years, with very large amounts released in population centers in Turkey, 1 the United States, 2 Hong Kong, 3 Greece, 4 Brazil, 5 Egypt, and Bahrain. 6, 7

Tear gas is generally perceived to be a sublethal incapacitant. 8 A 2003 analysis of several tear gases and incapacitants concluded that, on the basis of available toxicological evidence, commonly used tear gases have a large safety margin for life‐threatening or irreversible toxic effects. 9 Another medical review published in 2013 concluded that, in the majority of exposures, significant clinical effects are not anticipated. 10 However, there are debates surrounding the acceptability of tear gas use for riot‐control purposes, especially in the background of the recent massive use. Many believe the risks of tear gas exposure are understated and that perceived risks are based on insufficient human epidemiological and mechanistic data.

The major RCAs used since World War II include o‐chlorobenzylidene malononitrile (CS), oleoresin capsicum (OC, pepper spray), dibenz [ b, f]‐1,4‐oxazepine (CR), and 1‐chloroacetophenone (CN) 11 (Fig. ). The most commonly used RCA until the 1950s was CN, but a search for an alternative to CN was initiated in response to dissatisfaction with the potency and stability of the compound. 12 CS was discovered by two American scientists in 1928 ¹³ but was only developed for use as an RCA decades later. 14 This compound-considered to be more potent but less toxic than CN at that time-was adopted as the standard RCA of the U.S. Army in 1959. 12, 15 In the following decades, CS became the most common RCA, and it is now used widely. 16 CS, CN, and CR tear gas agents are electrophilic agents, and their structures are presented in Figure .

OC is a mixture of several compounds extracted from chili peppers, with capsaicin as the major active ingredient. 14 Pepper spray was developed as an animal repellent in the 1960s, but law enforcement agencies in the United States began using the compound for personal protection in the 1980s and 1990s. 11 The rise in popularity of OC was similar to the rise in popularity of CS: OC was adopted as a less dangerous alternative to Mace, an aerosol self‐defense spray whose primary component was CN. 11 CS and OC are now almost exclusively used as the RCAs of choice. The use of tear gas agents in warfare between military forces is banned under the 1993 International Chemical Weapons Convention, Geneva (Organisation for the Prohibition of Chemical Weapons), likely due to fear of escalation of chemical warfare. Some countries, including the United States, issued executive orders permitting the use of tear gas by military forces against rioting civilians and nonmilitary combatants and for troop extraction. 17 The domestic use of tear gas agents is not covered by the Geneva Convention. 17 Lack of epidemiological and mechanistic data on the spectrum of health effects of tear gas hinders the development of treatment plans and countermeasures and the medical understanding of long‐term effects. In this review, we summarize the existing epidemiological data on the health effects and biological mechanistic effects of tear gas agents and make recommendations to bridge the paucity of knowledge in this area.

Deployment technologies

Though commonly referred to as "tear gas," the active compounds are not actually gases but solids. RCAs are deployed in many different ways, as personal defense sprays or from grenades or canisters. 12 Sprays use a liquid formulation that is released from a pressurized dispenser, while grenades and canisters use a powdered form blended with a pyrotechnic mixture that can be aerosolized for dispersion as a smoke or fog. 12 A common solvent for sprays is methyl isobutyl ketone (hexone), which is also considered hazardous. 18, 19 CS tear gas agent is typically aerosolized as 3‐ to 10‐μm microencapsulated microparticles in aerosols. The typical pyrotechnic composition for dissemination of CS riot control agent consists of 45% CS agent, 30% potassium chlorate, 14% epoxy resin, 7% maleic anhydride, 3% methyl nadic anhydride, and 0.03% mixed residual balance. 20 Although the intrinsic toxicities of these ingredients in the pyrotechnic composition were not studied in detail, their safety data sheets show significant toxicities. These pyrotechnic devices can be thrown by hand or fired from launchers, engaging targets up to 400 m away and penetrating window glass, 12 with dispersion area ranges from 60 to 300 m ². 21 Aircraft‐ and vehicle‐mounted dispersers can be used for RCA deployment, and aerial drone-based RCA deployment systems have been tested and requested by several law enforcement agencies, with widespread adoption likely once the technology has sufficiently advanced. 12

Pepper spray (OC) is typically dispersed from a handheld canister. 21 However, it is also available in a number of different types of grenades and projectiles. 22 CN can be dissolved in a solvent, used in irritant sprays like Mace, or deployed from thermal grenades. 11

Health effects of tear gas exposures

Exposure to tear gas agents produces a wide spectrum of health effects, including acute and chronic effects. Studies have demonstrated specific receptor‐mediated mechanisms of action of tear gas agents. 23, 24 Whereas these specific receptors contribute to their acute painful and irritant effects, the electrophilic reactivity of the agents, together with the toxicities of solvents and pyrotechnic reaction products, engages multiple toxicological mechanisms that remain to be studied.

Immediate exposure effects

CS and OC produce similar symptoms. Acute CS exposure at concentrations generally used by law enforcement for riot‐control purposes results in instantaneous irritation to the eyes, nose, mouth, skin, and respiratory tract. 9 Dermal effects include itching, stinging, and redness, with potential blistering and allergic contact dermatitis. 25 Ocular exposure can result in lacrimation, blepharospasm, itching, and burning sensation. 26 When inhaled, CS often leads to coughing, choking, salivation, and chest tightness. 11 OC exposure causes pain and tingling in the respiratory tract, accompanied by coughing. 11 Signs and symptoms of OC contact with eyes include lacrimation, inflammation of the conjunctiva, blepharospasm, redness, pain, burning, and edema. 14 Some evidence indicates that OC may also temporarily inhibit the blink reflex and limit responsiveness to mechanical and chemical stimuli to the eye. 14 Like CS, dermal effects of OC can include pain, tingling, redness, swelling, and blistering. 14 The effects of CN are similar to those of CS and OC, 27 but are significantly more severe and potentially life threatening. CN is a more toxic lacrimator than CS and is more likely to cause serious injury to the skin. 11

Respiratory effects

Much of the research surrounding the effects of tear gas exposure was derived from laboratory animal research or from small studies of previously healthy individuals in controlled conditions, and several believe this level of research is inadequate for safety assessment. 17, 28 For example, one study concluding that tear gas exposure was not associated with increased airway resistance was conducted on a sample of only seven healthy military volunteers, and those with a history of chronic respiratory illness were excluded. 16 Tear gas use in riots or instances of large‐scale civil disorder could result in extended, repeated, or highly concentrated exposures, which pose a greater threat to respiratory health. 14, 29 High concentrations of CS or OC can cause severe respiratory symptoms, such as reactive airways dysfunction syndrome, in an individual exposed to both CS and OC and hemoptysis. 30, 31, 32 Capsaicin infiltration of the lower respiratory tract can induce pulmonary edema, apnea, and respiratory arrest. 11 Surveys performed after recent massive‐scale tear gas deployments in Turkey reported persistent cough, chest pain, sputum production, hemoptysis, breathing difficulties, and nasal discharge, sometimes lasting for weeks after exposure. 28 Lung function tests observed restriction and medium and small airway obstruction that was more severe in women. 22 Respiratory effects were also observed in residents of the areas where tear gas was deployed, suggesting that tear gas agents represent a persistent environmental health hazard. 29

Another Turkish study with 93 males frequently exposed to tear gas and 55 unexposed subjects found that tear gas-exposed subjects were at greater risk for chronic bronchitis. 33 A study of 34 young adults exposed to CS in a confined space during a confrontation with the police reported no long‐term sequelae. 34

CS‐induced respiratory illness during military training

Unexpected respiratory risks linked to tear gas exposures were discovered in epidemiological studies by the U.S. Army, analyzing health effects in more than 6000 army recruits exposed to CS in chambers during gas mask-confidence training. This relatively young and healthy population developed a high risk of presenting with acute respiratory illness in the time after CS exposure, with increasing risk at higher exposure concentrations. 35, 36 Exposure levels considered for many years safe and necessary for training were determined to far exceed the National Institute for Occupational and Safety and Health and Occupational Safety and Health Administration safety levels. 37 These findings led to immediate measures limiting exposure concentrations and times, improving decontamination procedures, and imposing frequent hygiene and health monitoring. Measures of respiratory illness included throat pain, cough, bronchitis, nasopharyngitis, sinusitis, and other indications. CS exposures were also associated with an increase in respiratory infections, including influenza. Follow‐up studies demonstrated that lowering CS exposures during training effectively reduced the risk for respiratory illness. 38 Whether these lower concentrations are also safe for diverse civilian populations remains unclear. Follow‐up epidemiological studies in military populations would represent a unique opportunity to identify potential long‐term health effects of tear gas exposures.

Ocular effects

Tear gas deployed at close range can cause severe ocular injuries, including corneal stromal edema, conjunctival tearing, and deep vascularization of the eye. 39 Other ocular complications include vitreous hemorrhage, traumatic optic neuropathy, symblepharon, pseudopterygium, infective keratitis, trophic keratopathy, glaucoma, and cataracts. 39 One report described four subjects who developed corneal erosion following exposure to pepper spray, indicating that OC or a solvent in the spray may cause nerve damage. 40

Skin burns and dermatitis

Physicians examining CS‐exposed patients often report skin burns, especially when large quantities are used, as in a case involving a riot at a Vietnamese refugee detention center in Hong Kong. 30, 32 Multiple cases of unusually severe skin reactions in response to CS exposure have been reported, including severe facial erythema and swelling that obscured vision. 41 Physicians from the Department of Dermatology at San Francisco General Hospital observed severe CS‐induced erythematous dermatitis of the face, neck, and hands. 42 Cases of allergic contact sensitization were reported with erythematous patches and multiple vesicular eruptions on the skin following heavy exposure to CS. 43 Ninety percent of workers in a plant manufacturing a CS agent reported a history of dermatitis on the arms and neck, with 7% showing positive patch‐test reactions to CS, suggesting that CS may act as a contact sensitizer. 44

Cardiovascular and gastrointestinal effects

Irritation of the gastrointestinal tract due to ingestion of compounds like CS may cause nausea, vomiting, diarrhea, and hematemesis. 14, 32 Various cardiovascular effects, including tachycardia and transient hypertension, have been observed in some individuals, likely initiated by sensory-autonomic reflexes or anxiety, pain, or psychological distress. 45

Severe injuries and deaths

There have been numerous case reports of injuries and fatalities associated with exposure to high concentrations of tear gas or exposure in enclosed spaces or for extended periods of time. Deaths and respiratory tract injuries were reported after release of tear gas in prisons. 46, 47, 48 CS and OC are increasingly used in prison systems, often in enclosed and poorly ventilated spaces. Deaths of inmates with preexisting respiratory conditions have been linked to multiple CS and OC exposures and lack of decontamination. 49 Other studies documented cases of death within 1 h of exposure to OC, though a direct causal link has not yet been established. 14 Severe injuries and deaths have been reported during the massive‐scale deployments of tear gas munitions in Egypt, Turkey, Bahrain, and Brazil. These were often caused by direct or close impact of tear gas munitions causing severe head and eye injuries and burns. 50, 51 A well‐documented case is the death of 37 Egyptian inmates in a prisoner van into which tear gas munitions were fired. 52 Circumstantial reports suggest a correlation between CS exposure and miscarriage. 16, 51, 53

Lack of epidemiological research in tear gas-exposed civilian populations and high‐risk groups

There is a significant amount of research examining the acute effects of RCA exposure among small samples of healthy individuals in controlled conditions, but little information has been gathered on the consequences of exposure in the field. A review on exposure to the CS tear gas agent attempted to compile case reports on the basis of PubMed and Scopus literature searches. 54 The real‐world conditions in which tear gas is used make it difficult to discriminate between the effects of different RCAs and to conduct effective epidemiological investigations. 16 It is often not possible to ascertain the exposure concentration and duration among exposed individuals, and weather or terrain factors can further complicate analysis. Because of the difficulties associated with conducting epidemiological investigations of RCA effects and the lack of public support for these studies, few epidemiological studies have been published, and the reliability of the results is often deficient. The situation is further complicated by the fact that research conducted by various military organizations is often classified, 55 and organizations may be denied access to health information during instances of civil unrest. 56

While prolonged exposure can lead to increased severity of symptoms, conclusions from past research indicated that most effects should resolve within minutes of removal from exposure. However, evidence supporting this conclusion came from significantly limited studies. For example, one oft‐cited study deemed CS tear gas safe on the basis of outcomes of controlled exposures of 35 healthy male volunteers, without considering the effects on children, women, the elderly, or subjects affected by preexisting conditions. 26 Deficiencies in the currently available research have impeded understanding of all of the risks potentially associated with chemical RCAs. The effects of RCA exposure among sensitive populations and among those with underlying health conditions are one such area where the level of risk is unclear. Individuals suffering from asthma or reactive airways disease could be at greater risk for more serious adverse effects from tear gas exposure, as chemical RCAs cause significant respiratory symptoms, which could plausibly be exacerbated in the presence of underlying respiratory illness. Current research on the issue, however, remains equivocal on the topic. A study of CS exposure in one group found no increase in airway resistance after exposure, but the study subjects only included healthy volunteers, and those with a history of asthma were excluded from the study. 16 A report of CS exposure in a nightclub indicated that patients with asthma experienced no greater sensitivity to the RCA, 57 and similar results were published in the report of an inquiry into a CS exposure in Londonderry in 1969. 58 However, according to a study of RCA exposure in South Korea, physicians reported that patients with asthma and chronic obstructive pulmonary disease experienced deterioration of lung function following tear gas exposure-some to a serious degree necessitating a longer stay at the hospital. 16

Other populations besides those with underlying respiratory conditions may also be at a greater susceptibility to harm from RCAs. The British Department of Health and other sources reported that individuals with hypertension or cardiovascular disease, as well as those taking neuroleptic medications, may be more susceptible to CS, calling for more research to be done in these populations. 11, 59 In one case study, a 40‐year‐old male was diagnosed with acute myocardial infarction (AMI) following exposure to pepper spray, indicating that OC could potentially be a triggering factor. 60 There is a strong relationship between inhalation of particulate matter and AMI. 61 While the acute pain and cardiorespiratory distress following exposure can contribute to triggering AMI, the consequences of inhalation of microencapsulated and precipitated particles, oil droplets, and particles generated during combustion from tear gas sprays or munitions need to be further investigated.

Biological targets and mechanisms

TRPV1: the target of capsaicin in pepper spray

The active noxious agent in pepper spray is capsaicin, purified and enriched from pungent chili peppers. The molecular target of capsaicin, TRPV1, was discovered in 1997. 62 TRPV1 is a transient receptor potential (TRP) ion channel expressed in nociceptors, the pain‐sensing peripheral sensory nerves of the trigeminal, vagal, and dorsal root ganglia (DRG). Nociceptor nerve endings are present in all organs and the body surface, including the skin, cornea, conjunctiva, and the mucous membranes of the upper and lower airways and lung. TRPV1 is a nonselective cation channel that, when activated by capsaicin, promotes neuronal depolarization. TRPV1 is also activated when nerve endings are exposed to noxious heat, acting as a thermal warning sensor for imminent tissue damage. Tissue acidification or acid exposures lead to sensitization or activation of TRPV1. TRPV1 is sensitized through signaling from a range of G protein-coupled receptors and receptor tyrosine kinases activated during injury and inflammation. These include the bradykinin receptor, prostaglandin receptors, nerve growth factor receptors, and cytokine and chemokine receptors.

TRPA1: the reactive irritant receptor mediating the acute effects of tear gas agents

The tear gas agents CS, CN, and CR are structurally dissimilar, suggesting they might bind to different targets (Fig. ). However, a single target, TRPA1, was identified as mediating the acute noxious effects of these agents and of many similarly acting chemical exposures. 24, 63 TRPA1 is also a TRP ion channel and, similar to TRPV1, is expressed in nociceptors. Pain neurobiological studies initially revealed that TRPA1 is the target of mustard oil (allyl isothiocyanate), the pain‐inducing and lachrymatory product in mustard, wasabi, and horseradish. 64 Together with capsaicin, mustard oil was used as an important chemical tool to characterize the function of nociceptor subtypes in pain transduction. Mustard oil is an electrophile, and TRPA1 was also found to be responsive to similar naturally occurring isothiocyanates and related compounds in onions and garlic. 64, 65 Isocyanates, such as mustard oil, are electrophiles thought to act as defensive agents of the plants against herbivores. Mustard oil is not to be mistaken with sulfur mustard and nitrogen mustard, the blistering agents belonging to a different class of chemical warfare agents in mustard gas. While these agents share a similar odor with mustard oil, mustard gas exposure is not immediately painful and has delayed effects.

Intriguingly, pretreatment of animals with capsaicin desensitized them to perceiving pain from mustard oil, suggesting that receptors for these agents may be expressed in the same nerve fibers, where they desensitize each other. Indeed, TRPV1 and TRPA1 were found to be expressed in the same population of nociceptors. Toxicological studies have shown that capsaicin pretreatment desensitizes neuronal responses to a wide range of chemical sensory irritants targeting nociceptors. One example is the volatile electrophile acrolein, an unsaturated aldehyde and the major airborne irritant in smoke from fires and combusted tobacco and in diesel exhaust. 66 Acrolein was used briefly as an irritant gas in warfare in World War I. Capsaicin pretreatment was shown to render mouse nasal trigeminal neurons unresponsive to airborne acrolein. 66 Studies in heterologous expression systems revealed that both rodent and human TRPA1 channels were activated by acrolein. 23 Similar effects were seen with croton aldehyde, another tobacco smoke aldehyde, and even saturated aldehydes, such as formaldehyde and acetaldehyde.

The discovery of TRPA1 as an electrophilic irritant receptor inspired additional studies that in 2008 identified TRPA1 as the principal target of the tear gas agents CN, CS, and CR, in vitro and in vivo. 24, 63 These three agents are among the most potent TRPA1 agonists known, with CS and CR activating human TRPA1 channels in the low nanomolar or subnanomolar range, more than 10,000‐fold more potent than mustard oil and other natural TRPA1 agonists. Modified electrophilic CR‐based chemicals were even more potent than the parent compound. 67 Mice with a targeted deletion in Trpa1 displayed no or only minimal acute pain behavior when exposed to CN or CS, confirming the essential role of TRPA1 in their sensory detection. 24 In human studies, the potency of tear gas agent derivatives toward TRPA1 showed clear correlation with their perceived irritancy, suggesting that TRPA1 also contributes to tear gas sensing in humans. 68

TRPA1 is activated by a large variety of structurally unrelated irritant chemicals. 69 This sensitivity to multiple chemicals cannot be explained by a traditional pharmacological ligand-receptor model. Biochemical studies revealed a reactivity‐based activation mechanism of TRPA1, in which electrophilic and oxidizing activators modify cysteine residues in the N‐terminal domain of TRPA1, resulting in covalent modification leading to channel activation. 70 Thus, TRPA1 can be considered a peripheral neuronal reactivity detector, signaling the danger of imminent injury by electrophilic or oxidant exposures.

Health effects related to TRP channel activation

The discovery of TRP ion channels as the primary sensory detectors for environmental, chemical, and physical stimuli in peripheral sensory neurons was a watershed in sensory neurobiology and pharmacology. While initial studies focused on the roles of TRPV1 and TRPA1 in pain, more recent discoveries revealed that these ion channels play fundamental roles in reflex responses in the respiratory, cardiovascular, digestive, and other organ systems and in acute and chronic inflammatory and degenerative conditions. These pathological mechanisms need to be taken into consideration when reassessing the acute and chronic health effects of tear gas exposures, especially in exposed individuals affected by chronic health conditions within a diverse civilian population.

Pain

Tear gas and pepper spray exposures cause immediate and severe pain leading to incapacitation. Ocular and nasal pain are sensed almost immediately and are initiated by activation of trigeminal nerve endings in the cornea and nasal passages that are highly sensitive to chemical exposures. Since TRPV1 and TRPA1 were identified as major pain‐initiating receptors, the pharmaceutical industry has developed a wide range of inhibitors for development as analgesics. Analgesic action was demonstrated in animal models of acute and inflammatory pain. In clinical trials, TRPV1 inhibitors alleviated heat‐induced pain, with moderate effects toward other pain modalities. The development of TRPA1 inhibitors began later, with clinical trials ongoing at this time.

Cough and airway obstruction

Cough is elicited when a chemical irritant activates vagal sensory nerve endings in the larynx. Vagal sensory nerves express higher levels of TRPV1 and TRPA1 than the trigeminal ganglia and DRG. Capsaicin is often used as a cough stimulus in clinical settings, and many airborne TRPA1 agonists are cough triggers. Tear gas and pepper spray exposures trigger cough directly but also cause profuse secretions within the airways due to sensory-autonomic reflexes. Secretions further aggravate cough and contribute to incapacitation by obstructing normal breathing and eliciting the fear of suffocation. Recent studies have implicated TRPA1 sensitization and heightened activity in chronic cough and cough hypersensitivity. 71

Asthma

Recent studies in animal models of allergen‐induced asthma have shown that TRPA1 plays a critical role in the initiation and maintenance of asthmatic inflammation, airway hyperreactivity, and smooth muscle contraction. 72, 73 Human genetic studies have associated polymorphisms in TRPA1 with reduced control of asthma. 74 Irritant‐induced asthma, manifesting as airway hyperreactivity following irritant inhalation, was also shown to depend on TRPA1. 75 With an asthma prevalence of 8.4% in the U.S. population and similar levels around the world, there is a high chance of exposure to tear gas and the development of complications in asthmatics. Indeed, the most severe complications reported after tear gas deployment involve asthma attacks. 34

Chronic obstructive pulmonary disorder and lung injury

TRPA1 is activated by many of the principal irritants in tobacco smoke, including acrolein, crotonaldehyde, and smoke particulates. 23, 74 In chronic smokers, inhalation of these irritants contributes to the etiology of chronic obstructive pulmonary disorder. TRPA1 has also been implicated in ventilator‐induced lung injury, in which mechanical stress and oxygen activate sensory neurons that may contribute to the observed inflammatory response. Activation of TRPA1 in the lung was shown to trigger the release of proinflammatory neuropeptides, such as CGRP, substance P, and neurokinin A. 24 While additional research is needed to delineate the role of TRPA1 in lung injury, these findings suggest that TRPA1 activation may aggravate preexisting pulmonary inflammation, injury, and remodeling processes in smokers and other affected individuals.

Cardiac arrhythmia

Irritant exposures have been linked to cardiovascular stress and sensory-autonomic dysregulation of cardiovascular function. Studies in rats prone to arrhythmia have shown that respiratory exposures to diesel exhaust or acrolein strongly increase the risk of arrhythmia through sympathetic activation. 76, 77 Rats treated with a TRPA1 inhibitor were resistant to exposure‐induced arrhythmias, suggesting that TRPA1 is a key chemical detector triggering circuits that alter cardiovascular control. 76, 77 Tear gas exposures may have similar effects in humans, suggesting that exposed individuals with preexisting cardiovascular conditions and arrhythmias may be at increased risk of developing cardiovascular complications.

Dermatitis and itch

TRPA1 agonists, such as mustard oil, are known to cause skin inflammation and edema that are diminished in TRPA1‐deficient mice. TRPA1 plays a key role in the neuronal control of skin inflammation and in the neuronal transduction of itch signals mediated by a specialized subpopulation of sensory neurons. 78 TRPA1 is coupled to pruritogen receptors and is essential for full development of inflammation and itch in hapten‐induced contact dermatitis. 78 Tear gas exposures of the skin cause pain, skin edema, and inflammation with itching. Tear gas agents can likely act as haptens themselves, and skin hypersensitivity reactions to tear gas agents, including allergic contact dermatitis, have been reported. 34, 43

Thus, atopic and exposed individuals affected by contact dermatitis may be at risk of developing adverse skin reactions. The appearance of clinical cutaneous symptoms varies widely from a few minutes to several weeks. A summary of dermal clinical symptoms following CS tear gas exposure and latency periods has been published. 54

Peripheral nerve damage

The analgesic properties of TRPA1 inhibitors are currently being tested in clinical trials in patients affected by diabetic neuropathy, a painful neurodegenerative condition. TRPA1 plays a key role in the peripheral neuronal hypersensitivity to metabolic stress in diabetic animal models. 79 Chronic TRPA1 activity leads to nerve calcium overload and excitotoxicity, resulting in chronic pain signaling and peripheral neurodegeneration, leading to loss of sensation or altered sensations. Other chemically induced neurodegenerative conditions were also linked to TRPA1, including chemotherapy‐induced neuropathies. 80 With more than 9% of the U.S. population affected by diabetes and diabetes rates approaching similar levels in other countries, this population needs to be considered at risk during tear gas exposures. Ligands of TRPV1 and TRPA1, when applied topically, are known to cause extensive desensitization and remodeling of cutaneous nerve endings. With tear gas agents being so highly potent, it is likely that similar effects occur. While desensitized nerve endings can recover and normal sensory capacity can be reestablished, high‐level exposures and local contamination may cause long‐term damage to the underlying sensory innervation.

TRP channel inhibitors as countermeasures against tear gas effects

At this time, no mechanism‐based countermeasures are available to alleviate the noxious effects of tear gas and pepper spray exposures. Countermeasures mostly involve decontamination strategies, including rinsing with water and buffered solutions, discarding contaminated clothing, and medical supportive treatment.

Highly potent and selective TRPV1 inhibitors have been developed and tested in animal studies and in clinical trials with proven efficacies for capsaicin‐induced and thermally induced pain. 81 It remains unclear whether these inhibitors will be developed further toward U.S. Food and Drug Administration approval for pain indications and will be considered for testing as countermeasures against pepper spray exposures.

A TRPA1 inhibitor was efficacious for prevention of tear gas agent (CN and CS) exposure-induced ocular pain in mice. 24 Since anti‐inflammatory and analgesic effects have been observed for TRPA1 inhibitors in multiple models of chemical injury and inflammation, it is highly likely that TRPA1 inhibitors will alleviate at least some of the tear gas-induced effects. There remains concern about the specificity and poor solubility of the tool compounds available for TRPA1 inhibition. The conclusion of clinical trials using TRPA1 inhibitors in diabetic neuropathic patients is eagerly awaited with the hope that more advanced inhibitors will be made available for testing in other conditions, including irritant and tear gas agent exposures.

Other targets of tear gas agents

Owing to their electrophilic properties, tear gas agents likely react with many other biomolecules in the eyes, respiratory tract, and skin. The nature of these targets is largely unknown. Similar to acrolein and related electrophiles, tear gas agents may damage and deplete biological redox systems in the lining fluids of epithelia and within cells and mitochondria, modify structural proteins and nucleic acids, and inactivate enzymes. There has been minimal research on endocrine effects, immunologic consequences, and histological changes from CS exposure, but some animal studies indicate that potential effects may occur. Studies in rats injected with CS found histological changes in the adrenal gland and the thyroid, though it is not clear whether dermal or inhalational exposure to CS in humans would result in a similar response. 82 Another study of CS exposure in mice reported suppression of the humoral immune response and elevated corticosteroid levels. 83 The mutagenicity and potential carcinogenic effects of RCAs are also not well understood, with research clearly lacking. Some laboratory studies indicate that CS is not mutagenic 84 or is weakly mutagenic, 85 but the results of carcinogenicity studies have not been confirmed, 86 and much of the research has been limited to laboratory studies rather than human studies. The mutagenicity of capsaicinoids has been tested extensively, but the results have been conflicting. 14 Dispersal of RCAs involving pyrotechnic mixtures can produce thermal degradation by‐products that could potentially be dangerous to human health. 87

Discussion and recommendations

The decision by law enforcement to use tear gas during civil disorder is understandable, as CN, CS, and OC are effective RCAs and reduce the risk of injury to law enforcement personnel and demonstrators when used instead of physical force. 10, 88 However, the massive increase in tear gas deployments worldwide, accompanied by advances in formulations and deployment technologies and the often‐observed absence or disregard of evidence‐based deployment rules and operating procedures, is of great concern. Epidemiological research on tear gas health effects is clearly deficient and has received little public support. Evidence from the limited epidemiological studies available and from case studies demonstrates that tear gas agents have the potential to cause serious harm and present specific threats to vulnerable populations, including children, women, and individuals affected by respiratory, cutaneous, and cardiovascular morbidities. While breakthroughs in mechanistic basic science have been made, discovering TRPV1 and TRPA1 as agent receptors, evidence that these targets are involved in multiple morbidities has not been taken into consideration for reassessment of tear gas use, and mechanism‐based countermeasures development has not progressed.

Based on these deficiencies, we make the following recommendations:

The toxicological effects of tear gas agents should be reassessed using state‐of‐the‐art toxicological techniques utilizing toxicology in the 21st century (Tox21) collaboration approaches ( https://www.epa.gov/chemical-research/toxicology-testing-21st-century-tox21) and animal models of respiratory, cutaneous, and cardiovascular morbidities, taking into account age and sex differences.

Epidemiological research networks should be established to develop standardized questionnaires; collect medical data, tissue, and fluid samples from exposed patients; curate biorepositories; perform environmental analysis; and conduct follow‐up investigations. Mandatory cooperation of law enforcement with this network before, during, and after deployment needs to be specified in standard operating procedures.

Epidemiological investigation of tear gas-exposed military populations should be extended to identify potential long‐term effects.

Efficient countermeasures need to be developed for treatment of individuals exposed to high levels of tear gas agents. Countermeasures should include new decontamination strategies based on the chemical properties of tear gas agents, their solvents, and pyrotechnic products and novel pharmacological inhibitors of the TRP ion channels TRPV1 and TRPA1, currently in clinical trials for pain indications.

Efforts must be made to make tear gas munitions traceable to document use volume, deployment locations, and numbers.

Efficient export and world trade controls must be enacted to prevent procurement and manufacture of RCAs by state actors and organizations that repeatedly deploy tear gas agents resulting in deaths, mass injuries, and widespread contamination and prohibit medical care and act against medical personnel treating the exposed.

Conflicts of interest

Sven‐Eric Jordt is serving on the Scientific Advisory Board of Hydra Biosciences Inc., a biopharmaceutical company developing TRP ion channel inhibitors for the treatment of pain and inflammation.

Acknowledgments

This work was supported by the NIH CounterACT Program; the Office of the Director, National Institutes of Health; and the National Institute of Environmental Health Sciences (NIEHS), Grant numbers U01ES015674 and R21ES022875 (to S‐E.J.) and R01ES15532 (to E.R.S.). [Correction added on October 7, 2016, after first online publication: The preceding Acknowledgments section was added.]

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Tear gas: an epidemiological and mechanistic reassessment

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Deployments of tear gas and pepper spray have rapidly increased worldwide. Large amounts of tear gas have been used in densely populated cities, including Cairo, Istanbul, Rio de Janeiro, Manama (Bahrain), and Hong Kong. In the United States, tear gas ...