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Air pollution is the world's top killer, according to new research

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Air pollution is the world's top killer, according to new research

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Burning fossil fuels is shortening lives globally by almost two years, a new study has found.

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Where EU air pollution is deadliest

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New data from the European Environment Agency shows the EU countries where air pollution causes the most premature deaths.

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Environment and Natural Resource Security

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Strategic Intelligence | World Economic Forum

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Strategic insights and contextual intelligence from the World Economic Forum. Explore and monitor the issues and forces driving transformational change across economies, industries and systems.

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Carbon dioxide (CO₂) Emissions

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UNdata | record view | Carbon dioxide (CO

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EUROPEAN VEHICLE MARKET STATISTICS

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Tech is rapidly shaking up the traditional healthcare market in ways that could be described as both exciting and terrifying. Fortunately for investors, these disruptions are also creating new opportunities to solve some of the biggest health-related challenges facing the world today.

The following infographic from MW Homecare shows how healthcare is being impacted by emerging technologies and startup companies.

Healthcare: the big picture

Today's healthcare industry faces many hurdles that are driving up costs. Political and economic uncertainty, an aging population, and a growing prevalence of chronic diseases are all contributing factors in the global push to find more cost-effective healthcare solutions.

The entire healthcare industry, from insurance providers to drug manufacturers, is seeking opportunities to reduce costs through modern technologies. This is playing into a wider trend towards a more personalized and efficient approach to healthcare. For investors, some of the most interesting crossroads between technology and healthcare may be found in big data, cybersecurity, developing markets, and strategic partnerships.

Big data

The collection and storage of large amounts of medical data, made possible by recent technological advancements, is helping healthcare professionals improve the quality of medical care, from research to diagnosis and treatment.

Investor interest in digital health startups that use big data to improve the efficiency and effectiveness of healthcare is increasing. These companies attracted $5.8 billion in funding in 2015, according to CB Insights - an increase of 20% over the previous year.

Cybersecurity

While technology is disrupting the healthcare industry in many positive ways, it's also creating new challenges that will need to be addressed with greater urgency moving forward. One issue is the world's growing reliance on cloud-based technology, which can place personal medical data at risk of security breaches.

Cyberattacks and IP theft are a growing threat to healthcare companies. According to Deloitte's 2016 Global Life Sciences Outlook, in 2011 the U.K. government claimed that its life sciences and healthcare industry suffered $2.9 billion in losses due to IP theft.

Investment into cybersecurity technology has grown by 235% over the last five years, reaching a total of $3.9 billion in 2015 alone, according to CB Insights.

Developing markets

Currently, each country has its own complex regulatory and compliance systems which act as gatekeepers in the development of medical products. While these systems are necessary in order to ensure the safety and credibility of products before they go to market, they often clash with technology's rapid pace of innovation.

Although the U.S. has been a leader in health tech innovation, current regulatory and compliance models tend to hold back progression. Digital health companies face heavy regulations in the U.S., which is causing investors to seek out new opportunities in developing markets such as China and India - two nations facing extreme healthcare costs against a backdrop of large aging populations and a rapid increase in chronic diseases such as cancer and diabetes.

China, with more than 185 million residents currently over the age of 60, is set to become the world's most aged society by 2030. The Chinese government has responded to this looming economic threat by opening up opportunities for private foreign investment into its healthcare sector. As part of China's recently implemented 13th Five-Year Plan, foreign senior care operators are now permitted to set up wholly-foreign owned enterprises (WFOE) in China, and are eligible to receive tax incentives, administrative fee exemptions and deductions and waivers. Chinese health companies are also seeking opportunities in foreign health technologies that will help China meet its domestic healthcare needs.

Strategic Partnerships

A trend that has been occurring with more frequency in recent years is the establishment of partnerships between tech giants and healthcare startups. For example, by partnering with Epic Systems in 2014, Apple's Healthkit platform was able to integrate substantial amounts of patient data to leverage its digital health and tracking technologies.

Mergers and acquisitions within the digital health tech space have also been steadily growing over the last few years. In fact 2016 has been a record-breaking year for digital health tech M&A, with 41 deals in total - a solid increase over 2015's total of 36 deals and 2014's total of 33 deals. Many of these mergers and acquisitions are strategic moves by healthcare retail companies looking to build up their marketing presence and customer interaction platforms.

As technology continues to act as a catalyst for rapidly changing market dynamics within the healthcare industry, it is likely that strategic partnerships, co-investments, and M&A will continue to be key drivers of growth.

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How Big Data Will Unlock the Potential of Healthcare

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Tech is rapidly shaking up the traditional healthcare market in ways that could be described as both exciting and terrifying. Fortunately for investors, these disruptions are also creating new opportunities to solve some of the biggest health-related challenges facing the world today.

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Air pollution consists of chemicals or particles in the air that can harm the health of humans, animals, and plants. It also damages buildings. Pollutants in the air take many forms. They can be gases, solid particles, or liquid droplets.

Sources of Air Pollution

Pollution enters the Earth's atmosphere in many different ways. Most air pollution is created by people, taking the form of emissions from factories, cars, planes, or aerosol cans. Second-hand cigarette smoke is also considered air pollution. These man-made sources of pollution are called anthropogenic sources.

Some types of air pollution, such as smoke from wildfires or ash from volcanoes, occur naturally. These are called natural sources.

Air pollution is most common in large cities where emissions from many different sources are concentrated. Sometimes, mountains or tall buildings prevent air pollution from spreading out. This air pollution often appears as a cloud making the air murky. It is called smog. The word "smog" comes from combining the words "smoke" and "fog."

Large cities in poor and developing nations tend to have more air pollution than cities in developed nations. According to the World Health Organization (WHO), some of the worlds most polluted cities are Karachi, Pakistan; New Delhi, India; Beijing, China; Lima, Peru; and Cairo, Egypt. However, many developed nations also have air pollution problems. Los Angeles, California, is nicknamed Smog City.

Air pollution is usually thought of as smoke from large factories or exhaust from vehicles. But there are many types of indoor air pollution as well.

Heating a house by burning substances such as kerosene, wood, and coal can contaminate the air inside the house. Ash and smoke make breathing difficult, and they can stick to walls, food, and clothing.

Naturally-occurring radon gas, a cancer-causing material, can also build up in homes. Radon is released through the surface of the Earth. Inexpensive systems installed by professionals can reduce radon levels.

Some construction materials, including insulation, are also dangerous to people's health. In addition, ventilation, or air movement, in homes and rooms can lead to the spread of toxic mold. A single colony of mold may exist in a damp, cool place in a house, such as between walls. The mold's spores enter the air and spread throughout the house. People can become sick from breathing in the spores.
Indoor Air Pollution
Effects On Humans

People experience a wide range of health effects from being exposed to air pollution. Effects can be broken down into short-term effects and long-term effects.

Short-term effects, which are temporary, include illnesses such as pneumonia or bronchitis. They also include discomfort such as irritation to the nose, throat, eyes, or skin. Air pollution can also cause headaches, dizziness, and nausea. Bad smells made by factories, garbage, or sewer systems are considered air pollution, too. These odors are less serious but still unpleasant.

Long-term effects of air pollution can last for years or for an entire lifetime. They can even lead to a person's death. Long-term health effects from air pollution include heart disease, lung cancer, and respiratory diseases such as emphysema. Air pollution can also cause long-term damage to people's nerves, brain, kidneys, liver, and other organs. Some scientists suspect air pollutants cause birth defects. Nearly 2.5 million people die worldwide each year from the effects of outdoor or indoor air pollution.

People react differently to different types of air pollution. Young children and older adults, whose immune systems tend to be weaker, are often more sensitive to pollution. Conditions such as asthma, heart disease, and lung disease can be made worse by exposure to air pollution. The length of exposure and amount and type of pollutants are also factors.

Effects On The Environment

Like people, animals, and plants, entire ecosystems can suffer effects from air pollution. Haze, like smog, is a visible type of air pollution that obscures shapes and colors. Hazy air pollution can even muffle sounds.

Air pollution particles eventually fall back to Earth. Air pollution can directly contaminate the surface of bodies of water and soil. This can kill crops or reduce their yield. It can kill young trees and other plants.

Sulfur dioxide and nitrogen oxide particles in the air, can create acid rain when they mix with water and oxygen in the atmosphere. These air pollutants come mostly from coal-fired power plants and motor vehicles. When acid rain falls to Earth, it damages plants by changing soil composition; degrades water quality in rivers, lakes and streams; damages crops; and can cause buildings and monuments to decay.

Like humans, animals can suffer health effects from exposure to air pollution. Birth defects, diseases, and lower reproductive rates have all been attributed to air pollution.

Global warming is an environmental phenomenon caused by natural and anthropogenic air pollution. It refers to rising air and ocean temperatures around the world. This temperature rise is at least partially caused by an increase in the amount of greenhouse gases in the atmosphere. Greenhouse gases trap heat energy in the Earths atmosphere. (Usually, more of Earths heat escapes into space.)

Carbon dioxide is a greenhouse gas that has had the biggest effect on global warming. Carbon dioxide is emitted into the atmosphere by burning fossil fuels (coal, gasoline, and natural gas). Humans have come to rely on fossil fuels to power cars and planes, heat homes, and run factories. Doing these things pollutes the air with carbon dioxide.

Other greenhouse gases emitted by natural and artificial sources also include methane, nitrous oxide, and fluorinated gases. Methane is a major emission from coal plants and agricultural processes. Nitrous oxide is a common emission from industrial factories, agriculture, and the burning of fossil fuels in cars. Fluorinated gases, such as hydrofluorocarbons, are emitted by industry. Fluorinated gases are often used instead of gases such as chlorofluorocarbons (CFCs). CFCs have been outlawed in many places because they deplete the ozone layer.

Worldwide, many countries have taken steps to reduce or limit greenhouse gas emissions to combat global warming. The Kyoto Protocol, first adopted in Kyoto, Japan, in 1997, is an agreement between 183 countries that they will work to reduce their carbon dioxide emissions. The United States has not signed that treaty.

Regulation

In addition to the international Kyoto Protocol, most developed nations have adopted laws to regulate emissions and reduce air pollution. In the United States, debate is under way about a system called cap and trade to limit emissions. This system would cap, or place a limit, on the amount of pollution a company is allowed. Companies that exceeded their cap would have to pay. Companies that polluted less than their cap could trade or sell their remaining pollution allowance to other companies. Cap and trade would essentially pay companies to limit pollution.

In 2006 the World Health Organization issued new Air Quality Guidelines. The WHOs guidelines are tougher than most individual countries existing guidelines. The WHO guidelines aim to reduce air pollution-related deaths by 15 percent a year.

Reduction

Anybody can take steps to reduce air pollution. Millions of people every day make simple changes in their lives to do this. Taking public transportation instead of driving a car, or riding a bike instead of traveling in carbon dioxide-emitting vehicles are a couple of ways to reduce air pollution. Avoiding aerosol cans, recycling yard trimmings instead of burning them, and not smoking cigarettes are others. Global Warming

Fast Fact

Downwinders
The United States conducted tests of nuclear weapons at the Nevada Test Site in southern Nevada in the 1950s. These tests sent invisible radioactive particles into the atmosphere. These air pollution particles traveled with wind currents, eventually falling to Earth, sometimes hundreds of miles away in states including Idaho, Utah, Arizona, and Washington. These areas were considered to be "downwind" from the Nevada Test Site.

Decades later, people living in those downwind areascalled "downwinders"began developing cancer at above-normal rates. In 1990, the U.S. government passed the Radiation Exposure Compensation Act. This law entitles some downwinders to payments of $50,000.

Fast Fact

London Smog
What has come to be known as the London Smog of 1952, or the Great Smog of 1952, was a four-day incident that sickened 100,000 people and caused as many as 12,000 deaths. Very cold weather in December 1952 led residents of London, England, to burn more coal to keep warm. Smoke and other pollutants became trapped by a thick fog that settled over the city. The polluted fog became so thick that people could only see a few meters in front of them.

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Air pollution consists of chemicals or particles in the air that can harm the health of humans, animals, and plants. It also damages buildings.

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Show the 1980 Mount St. Helens Eruption photograph. Tell students that there are two types of pollutants: visible pollutants and invisible pollutants. Ask:

What kind of pollutants can you see in this picture? (You can see ash emitted, rock fragments, and gas clouds.)

Tell students that there are many different types of invisible, or gaseous, pollutants. Let students know that they will be exploring the sources of visible and invisible pollutants and their effects on human and environmental health in this activity.
2. Discuss the role of uncertainty in the scientific process.
Tell students that science is a process of learning how the world works and that scientists do not know the "right" answers when they start to investigate a question. Let students know that they can see examples of scientists' uncertainty in forecasting air quality. Tell students that air quality is measured by the Air Quality Index. Show students the Air Quality Index, which includes explanations of the ranges used in the air quality index. Then project the Forecast of Air Quality on December 10, 2013 image and Air Quality on December 10, 2013 ﻿image. (Click on the link in the media carousel above and download using the arrow in the lower right corner of the window.) Tell students that these are snapshots of the air quality forecast and the real-time air quality in the United States on December 10, 2013. Ask:

Did the forecast accurately predict which areas would have poor quality air? (The forecast air quality overlaps with many of the poor air quality areas, but it does not cover all of them. The air quality in some areas [Northern California] is much worse than the forecast predicted.)

Why do you think scientists did not accurately predict the air quality for more of the United States? (Student answers will vary. The air quality forecast is affected by human activities that may not be easily predicted.)

Tell students that they will be asked questions about the certainty of their predictions. Let students know they should think about what scientific data is available as they assess their certainty with their answers, and encourage them to discuss the scientific evidence with each other to better assess their level of certainty with their predictions.
3. Introduce the concept of stocks and flows in a system.
Tell students that materials flow into and out of systems. The flow of the materials over time can change and can be influenced by many different factors and interacting parts. Scientists think about how one part of the system can affect other parts of the system. Give students a simple example of a stock and flow in a system, as described in the scenario below.

There is a bathtub with water flowing in from the faucet and water leaving through the drain. Ask:

﻿When the drain is plugged, what happens to the level of water in the bathtub? ﻿(The water level will increase because the outflow of water is stopped, but water keeps coming in from the faucet.)

﻿When the faucet is turned off, what happens to the level of water in the bathtub? ﻿(The water level will decrease because the inflow of water is stopped, but the water keeps leaving through the drain.)

﻿How can the level of water in the bathtub be kept at the same level? ﻿(The water in the bathtub can be kept at the same level by making the inflow equal to the outflow. Then, the water that comes in through the faucet will be offset by the water that leaves through the drain.)

Tell students they will be following the flow of materials, in this case the amount of air pollution, in the system. Let students know they will be exploring some environmental and human factors that contribute to changes in the amount of pollution being added to and removed from the modeled system.
4. Have students launch the Visible and Invisible Pollutants interactive.
Provide students with the link to the Visible and Invisible Pollutants interactive. Divide students into groups of two or three, with two being the ideal grouping to allow groups to share a computer workstation. Tell students that they will be working through a series of pages of data with questions related to the data. Ask students to work through the interactive in their groups, discussing and responding to questions as they go.

NOTE: You can access the Answer Key for students' questions-and save students' data for online grading-through a free registration on the High-Adventure Science portal page.
5. Discuss the issues.
Tell students that this is Activity 4 of the Will the Air Be Clean Enough to Breathe? lesson.

After students have completed the activity, bring the groups back together and lead a discussion focusing on these questions:

What types of particulate pollutants are produced naturally, and what types are produced through human actions? (Some natural particulates include sand and salt particles, as well as ash and soot from forest fires. Ash and soot are also produced through human actions as materials are burned for fuel in transportation, heating, and electricity production. Humans cause some forest fires, making those "natural" sources really anthropogenic sources.)

﻿How do invisible (gaseous) pollutants affect the environment? ﻿(Invisible pollutants such as SO₂ and NOx can combine with water to form acidic precipitation. The acidic precipitation can harm plants and animals. VOCs and CO are harmful to animals' health as well as human health.)

Why are particulate pollutants hazardous to human health? (Particulates can be inhaled deep into the lungs and cross over into the bloodstream. Then they can travel around the body, causing effects to many organ systems.)

Show the NOx Emissions, 2008 pie chart﻿(page 6 of the interactive). How many of the NOx emissions are from human sources? (Almost all of the NOx emissions are anthropogenic. Up to 1% [miscellaneous and fires] could be from natural sources.)

What types of materials can cause indoor air pollution? (Carpets, perfumes, hairsprays, furniture, and poorly ventilated heating/cooking devices can cause indoor air pollution.)

Why is indoor pollution more hazardous to human health than most outdoor pollution? (Indoor pollution cannot be blown away by the wind or precipitated out of the air by rain or snow. It can be more concentrated because there is less dilution with clean air than is possible outdoors.)

How can increasing fuel efficiency reduce the emissions of gaseous pollutants (SO₂, NOx, CO)? (Increasing fuel efficiency can reduce the emissions of gaseous pollutants because less fuel needs to be burned to go the same distance [in a vehicle] or produce electricity [in a power plant]. If less fuel is used, there will be fewer emissions.)

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Show the 1980 Mount St. Helens Eruption photograph. Tell students that there are two types of pollutants: visible pollutants and invisible pollutants. Ask: What kind of pollutants can you see in this picture? (You can see ash emitted, rock fragments, and gas clouds.) Tell students that there are many different types of invisible, or gaseous, pollutants.

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This lists the logos of programs or partners of NG Education which have provided or contributed the content on this page. Content Created by

Directions Objectives Preparation Background & Vocabulary

Students will learn how to create a good scientific argument in the context of air quality science. They will continuously encounter questions that ask them to make a claim, explain their answer, rate their certainty with their answer, and explain that rating.

DIRECTIONS

Tell students that Activity 1 (Constructing an Argument) of the lesson Will the Air Be Clean Enough To Breathe? introduces the structure of the scientific argumentation they will be asked to do in the rest of the lesson. Tell students that Activity 1 will give them practice with analyzing a data set and making a good scientific argument from the evidence. Encourage students to review the questions and example best answers provided in Activity 1 before starting on the current activity.

Objectives

Students will:

explain how gaseous emissions can result in acid rain

explain the link between human and ecosystem health and air pollution

describe natural and anthropogenic sources of air pollution

identify factors that affect air quality over a given area

describe how pollutants move through the atmosphere

create a good scientific argument in the context of air quality science

explain how precipitation can improve air quality over an area

identify common sources of particulate and gaseous pollutants

explain how particulate emissions affect human health

describe why intense sunlight can decrease air quality in a pollution event

explain how human health is affected by gaseous pollutants such as VOCs and carbon monoxide

explain how air movements affect the air quality over a given area

describe the effect of solar intensity on the formation of ozone

explain the effect of precipitation on the concentration of pollutants in the atmosphere

explain how acid rain is formed from primary pollutants

describe how a thermal inversion occurs and is dissipated

explain how pollution control devices reduce emissions of pollutants from vehicles and smokestacks

compare methods of transportation for their ability to prevent/reduce the number of bad air quality days

Teaching Approach

Inquiry-based learning

Learning-for-use

Teaching Methods

Discussions

Multimedia instruction

Self-directed learning

Self-paced learning

Visual instruction

Writing

Skills Summary

This lesson targets the following skills:

21st Century Student Outcomes

Information, Media, and Technology Skills

Learning and Innovation Skills

21st Century Themes

Critical Thinking Skills

Analyzing

Evaluating

Understanding

Connections to National Standards, Principles, and Practices

National Science Education Standards (5-8) Standard A-1: Abilities necessary to do scientific inquiry (5-8) Standard D-1: Structure of the earth system (5-8) Standard F-1: Personal health (5-8) Standard F-4: Risks and benefits (9-12) Standard A-1: Abilities necessary to do scientific inquiry (9-12) Standard A-2: Understandings about scientific inquiry (9-12) Standard C-5: Matter, energy, and organization in living systems (9-12) Standard F-1: Personal and community health (9-12) Standard F-2: Population growth (9-12) Standard F-4: Environmental quality (9-12) Standard F-5: Natural and human-induced hazardsCommon Core State Standards for English Language Arts & Literacy Reading Standards for Literacy in Science and Technical Subjects 6-12: Key Ideas and Details, RST.11-12.3 Reading Standards for Literacy in Science and Technical Subjects 6-12: Key Ideas and Details, RST.6-8.1 Reading Standards for Literacy in Science and Technical Subjects 6-12: Key Ideas and Details, RST.6-8.3 Reading Standards for Literacy in Science and Technical Subjects 6-12: Craft and Structure, RST.6-8.4 Reading Standards for Literacy in Science and Technical Subjects 6-12: Key Ideas and Details, RST.9-10.1 Reading Standards for Literacy in Science and Technical Subjects 6-12: Key Ideas and Details, RST.9-10.3 Reading Standards for Literacy in Science and Technical Subjects 6-12: Craft and Structure, RST.9-10.4 Reading Standards for Literacy in Science and Technical Subjects 6-12: Key Ideas and Details, RST.11-12.1 Reading Standards for Literacy in Science and Technical Subjects 6-12: Craft and Structure, RST.11-12.4ISTE Standards for Students (ISTE Standards*S) Standard 3: Research and Information Fluency Standard 4: Critical Thinking, Problem Solving, and Decision Making Next Generation Science Standards Crosscutting Concept 1: Patterns Crosscutting Concept 2: Cause and effect: Mechanism and prediction Crosscutting Concept 3: Scale, proportion, and quantity Crosscutting Concept 4: Systems and system models Crosscutting Concept 5: Energy and matter: Flows, cycles, and conservation Crosscutting Concept 7: Stability and change HS. Earth's Systems: HS-ESS3-4. Evaluate or refine a technological solution that reduces impacts of human activities on natural systems. Science and Engineering Practice 1: Asking questions and defining problems Science and Engineering Practice 2: Developing and using models Science and Engineering Practice 3: Planning and carrying out investigations Science and Engineering Practice 4: Analyzing and interpreting data Science and Engineering Practice 5: Using mathematics and computational thinking Science and Engineering Practice 6: Constructing explanations and designing solutions Science and Engineering Practice 7: Engaging in argument from evidence Science and Engineering Practice 8: Obtaining, evaluating, and communicating information

What You'll Need

Required Technology

Internet Access: Required

Internet access: Required

Tech Setup: 1 computer per learner, 1 computer per small group, Interactive whiteboard, Projector

Physical Space

Classroom

Computer lab

Media Center/Library

Setup

Grouping

Heterogeneous grouping

Homogeneous grouping

Large-group instruction

Small-group instruction

Accessibility Notes

Background Information

Recommended Prior Lessons

Vocabulary

layers of gases surrounding a planet or other celestial body.

a mathematical model that requires extensive computational resources to study the behavior of a complex system by computer simulation.

all forms in which water falls to Earth from the atmosphere.

type of air pollution common in manufacturing areas or areas with high traffic.

For Further Exploration

Websites

Tips & Modifications

Tip Teacher Tip

If you want to save students' data for grading online, register your class for free at the High-Adventure Science portal page.

Tip

This activity is in a sequence of activities in the Will the Air Be Clean Enough to Breathe? lesson. The activities work best if usedin sequence.

Modification

This activity may be used individually or in groups of two or three students. It may also be modified for a whole-class format. If using as a whole-class activity, use an LCD projector or interactive whiteboard to project the activity. Turn embedded questions into class discussions. Uncertainty items allow for classroom debates over the evidence.

Credits

Media Credits

The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.

Researcher

Amy Pallant, Principal Investigator, The Concord Consortium

Writer

Sarah Pryputniewicz, The Concord Consortium

Editor

Elaine Larson, National Geographic Society
Sarah Pryputniewicz, The Concord Consortium

Copyeditor

Jeannie Evers, Emdash Editing

Factchecker

The Concord Consortium

Other

This material is based upon work supported by the National Science Foundation under Grant No. DRL-1220756. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

User Permissions

For information on user permissions, please read our Terms of Service. If you have questions about licensing content on this page, please contact ngimagecollection@natgeo.com for more information and to obtain a license. If you have questions about how to cite anything on our website in your project or classroom presentation, please visit our FAQ page.

Media

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Text

Text on this page is printable and can be used according to our Terms of Service.

Interactives

Any interactives on this page can only be played while you are visiting our website. You cannot download interactives.

Jeannie Evers, Emdash Editing

The Concord Consortium

# data[].attributes.attachment_link.title
Will the Air Be Clean Enough To Breathe?

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In this lesson, students explore the question, will the air be clean enough to breathe? They will be guided through the analysis of models and real-world data as they explore the interactions of factors that affect a region's air quality.

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Air pollution is one of the world's largest health and environmental problems. It develops in two contexts: indoor (household) air pollution and outdoor air pollution.

We look in detail at the data and research on the health impacts of Indoor Air Pollution, attributed deaths, and its causes across the world in our full entry: Indoor Air Pollution.

We look in detail at how exposure to Outdoor Air Pollution, its health impacts and attributed deaths across the world in our full entry: Outdoor Air Pollution.

In this entry we look at the aggregate picture of air pollution - both indoor and outdoor.
Related research entries
Outdoor air pollution - attributed to 3.4 million deaths each year, outdoor air pollution is one of the world's largest health problems. How do the health impacts of outdoor air pollution vary across the world?

Indoor air pollution - indoor air pollution is a major health problem, especially for poorer households across the world.

Energy access - how does access to electricity and clean cooking fuels compare across the world?

Fossil fuels - how is the production and consumption of fossil fuels changing?

Causes of death - what are people across the world dying from?

Air pollution is one of the world's leading risk factors for death

Air pollution is responsible for 5 million deaths each year

Air pollution - the combination of outdoor and indoor particulate matter, and ozone - is a risk factor for many of the leading causes of death including heart disease, stroke, lower respiratory infections, lung cancer, diabetes and chronic obstructive pulmonary disease (COPD).

The Institute for Health Metrics and Evaluation (IHME) in its Global Burden of Disease study provide estimates of the number of deaths attributed to the range of risk factors for disease.

In the visualization we see the number of deaths per year attributed to each risk factor. This chart is shown for the global total, but can be explored for any country or region using the "change country" toggle.

Air pollution is one of the leading risk factors for death. In low-income countries it tops the list. In 2017, it was responsible for an estimated 5 million deaths globally. That means it contributed to 9% - nearly 1-in-10 - deaths.

Air pollution contributes to 9% of deaths globally - this varies from 2% to 15% by country

Globally, air pollution contributed to 9% of deaths in 2017.

In the map shown here we see the share of deaths attributed to air pollution across the world. In 2017, this ranged from a low of 2% across high-income countries, to close to 15% across many countries in South and East Asia.

Air pollution is one of the leading risk factors for disease burden

Air pollution is one of the leading risk factors for death. But its impacts go even further, also being one of the main contributors to global disease burden.

Global disease burden takes into account not only years of life lost to early death, but also the number of years lived in poor health.

In the visualization we see risk factors ranked in order of DALYs - disability-adjusted life years - the metric used to assess disease burden. Again, air pollution is near the top of the list making it one of the leading risk factors for poor health across the world.

Air pollution not only takes years from peoples' lives, but also had large effect on quality while they're still living.

Who is most affected by air pollution?

Death rates from air pollution are highest in low-to-middle income countries

Air pollution is a health and environmental issue across all countries of the world, but with large differences in severity.

In the interactive map we show death rates from air pollution across the world, measured as the number of deaths per 100,000 people of a given country or region.

We see that the death rates tend to be highest across Sub-Saharan Africa and South Asia. This highlights the large differences globally: death rates in the highest burden countries are more than 100 times greater than across much of Europe and North America.

The burden of air pollution tends to be greater across both low and middle income countries for two reasons: indoor pollution rates tend to be high in low-income countries due to a reliance on solid fuels for cooking; and outdoor air pollution tends to increase as countries industrialize and shift from low-to-middle incomes.

A map of the number deaths from air pollution by country can be found here.

How are death rates from air pollution changing?

Death rates from air pollution are falling - mainly due to improvements in indoor pollution

In the visualization we show global death rates from air pollution over time - shown as the total air pollution, in addition to the individual contributions from outdoor and indoor pollution.

Globally we see that in recent decades the death rates from total air pollution has declined: since 1990 the number of deaths per 100,000 people have nearly halved. But, as we see from the breakdown, this decline has been primarily driven by improvements in indoor air pollution.

Death rates from indoor air pollution have seen an impressive decline, whilst improvements in outdoor pollution have been much more modest.

You can explore this data for any country or region using the "change country" toggle on the interactive chart.

Outdoor air pollution

Indoor air pollution

Data Sources

IHME Global Burden of Disease

State of Global Air

Data: National average PM2.5 and ozone (O3) concentrations, 1990-2015

Geographical coverage: Global - by country

Time span: 1990 onwards

Available at: https://www.stateofglobalair.org/data

State of Global Air

Data: Age-standardized death rates, DALY rates, absolute number of deaths, and absolute DALY from PM2.5 exposure

Geographical coverage: Global - by country

Time span: 1990 onwards

Available at: https://www.stateofglobalair.org/data

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Air pollution is one of the world's largest health and environmental problems. It develops in two contexts: indoor (household) air pollution and outdoor air pollution. We look in detail at the data and research on the health impacts of Indoor Air Pollution, attributed deaths, and its causes across the world in our full entry: Indoor Air Pollution .

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Search for "pollution" - Visual Capitalist

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Data-driven visuals that help explain a complex world

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>50% of all steel, cement, nickel, and copper goes there
The Chart of the Week is a weekly Visual Capitalist feature on Fridays.
It's said that in China, a new skyscraper is built every five days.

China is building often, and they are building higher. In fact, just last year, China completed 77 of the world's 144 new supertall buildings, spread through 36 different Chinese cities. These are structures with a minimum height of 656 feet (200 meters).

For comparison's sake, there are only 113 buildings in New York City's current skyline that are over 600 feet.

Unbelievable Scale

It's always hard to put China's size and scope in perspective - and we've tried before by showing you 35 Chinese cities as big as countries, or highlighting the growing prominence of the domestic tech scene.

Today's chart also falls in that category, and it focuses in on the raw materials that are needed to make all this growth possible.
Note: Because this data is not all in one easy place, it is sourced from many different industry associations, banks, and publications. Most of the data comes from 2017, but some is from 2016.
China Demand > World

There are five particularly interesting commodity categories here - and in all of them, China's demand equals or exceeds that of the rest of the world combined.

Cement: 59%
The primary ingredient in concrete is needed for roads, buildings, engineering structures (bridges, dams, etc.), foundations, and in making joints for drains and pipes.

Nickel: 57%
Nickel's primary use is in making stainless steel, which is corrosion resistant. It also gets used in superalloys, batteries, and an array of other uses.

Steel: 50%
Steel is used for pretty much everything, but demand is primarily driven by the construction, machinery, and automotive sectors.

Copper: 50%
Copper is one of the metals driving the green revolution, and it's used in electronics, wiring, construction, machinery, and automotive sectors, primarily.

Coal: 50%
China's winding down coal usage - but when you have 1.4 billion people demanding power, it has to be done with that in mind. China has already hit peak coal, but the fossil fuel does still account for 65% of the country's power generated by source.

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Every Coal Power Plant in the World (1927-2019)

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The Chart of the Week is a weekly Visual Capitalist feature on Fridays. It's said that in China, a new skyscraper is built every five days. China is building often, and they are building higher. In fact, just last year, China completed 77 of the world's 144 new supertall buildings, spread through 36 different Chinese cities.

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Ragazzi - Youth Panel Italia

L'abuso di internet causa negli adolescenti insonnia e risvegli notturni sempre più frequenti. Gli adulti, spesso, ignari di quello che accade ai loro figli. Smartphone e social stanno contribuendo all'aumento dei casi di cyberbullismo e ad un sonno di cattiva qualità o ad una vera e propria insonnia. Sono alcuni dei problemi degli adolescenti evidenziati dall'indagine "Adolescenti e Stili di Vita". L'indagine è stata condotta dall'Associazione Culturale Pediatri e l'Osservatorio Permanente Giovani ed Alcol, tra il 2018 e il 2019, su oltre 2000 studenti di scuole secondarie. È così

emerso che, circa, il 60% dei ragazzi ha avuto il suo primo cellulare tra i 10 e gli 11 anni. Precoce anche l'uso dei social: il 54% inizia infatti tra gli 11 e i 12. Uno degli effetti collaterali dell'uso precoce di social e telefonini è il cyberbullismo, con cui è entrato in contatto il 40% dei giovani. Solo il 6,8% degli intervistati dorme almeno 9 ore per notte, mentre il 20% meno di 7 ore. Inoltre, i ragazzi hanno problemi ad addormentarsi e i risvegli notturni sono sempre più frequenti. Il telefonino e i social sono gli immancabili compagni di insonnia degli adolescenti. La maggioranza non lo spegne prima di andare a dormire. Privi di controllo da parte dei propri genitori, i giovani non adoperano neppure strumenti per difesa dei propri profili social e ciò li rende vulnerabili. Alle scuole l'ingrato compito di educarli all'uso della rete anche se le famiglie dovrebbero fungere da prima formazione.

Questa è la raccomandazione della Commissione bicamerale per l'Infanzia e l'Adolescenza, che ha condotto un'indagine conoscitiva su Bullismo e Cyberbullismo. La Commissione propone una serie di integrazioni. A cominciare dal maggiore coinvolgimento delle famiglie: i genitori - spiega la Commissione - devono presidiare l'uso delle tecnologie da parte dei ragazzi e, in questo contesto, "sarebbe necessario anche potenziare la formazione delle famiglie" sulla rete e sui rischi ad essa collegati.

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SIC Italia - Dipendenza da internet: giovani trasformati in zombie dai telefonini

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Ragazzi - Youth Panel Italia L'abuso di internet causa negli adolescenti insonnia e risvegli notturni sempre più frequenti. Gli adulti, spesso, ignari di quello che accade ai loro figli. Smartphone e social stanno contribuendo all'aumento dei casi di cyberbullismo e ad un sonno di cattiva qualità o ad una vera e propria insonnia.

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Quando lo smartphone crea una vera dipendenza

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CHAT

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Making magic in traffic with a smartphone

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Sul pianeta oggi ci sono più schede Sim che persone: 7,8 miliardi di sottoscrizioni alla telefonia mobile contro i 7,5 miliardi di abitanti. Noi italiani siamo i terzi al mondo per diffusione capillare del cellulare, con più di otto persone su 10 che ne hanno uno. Lo smartphone è qualcosa che ci rassicura, che ci tranquillizza e ci rende meno ansiosi. Le persone si svegliano durante la notte e per prima cosa guardano il telefonino. Poi si tranquillizzano e si rimettono a dormire. Il punto, dicono i neuroscienziati, è che stiamo allenando il nostro cervello a pensare esattamente nella stessa maniera in cui utilizziamo lo smartphone. Saltiamo da un pensiero all'altro così come saltiamo da un link all'altro. Tutto è diventato cliccabile, downloadabile. Ma quali sono le conseguenze sulla nostra capacità di capire davvero quello che leggiamo, di memorizzare? Cosa sta succedendo al nostro cervello?

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Presadiretta 2018/19 - Iperconnessi - Video - RaiPlay

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Sul pianeta oggi ci sono più schede Sim che persone: 7,8 miliardi di sottoscrizioni alla telefonia mobile contro i 7,5 miliardi di abitanti. Noi italiani siamo i terzi al mondo per diffusione capillare del cellulare, con più di otto persone su 10 che ne hanno uno.

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The Next Generations

From developmental delays to suicide, children face a host of physical, mental and social challenges

Evidence

Making Sense of the World

Misinformation, conspiracy theories, and fake news

Evidence

Attention and Cognition

Loss of crucial abilities including memory and focus

Evidence

The level of social media use on a given day is linked to a significant correlated increase in memory failure the next day. Assessing nearly 800 people aged 25-75, research showed similar effects irrespective of age and of the user's memory levels on previous days. These effects occur in one direction only: levels of social media use predict later memory failure, but levels of memory failure do not predict social media use on subsequent days.

Our memory systems automatically prioritize superficial social text over more complex forms of text. For example, after reading news online, people are significantly better at remembering other readers' comments rather than sentences from the article itself or even its headline; this is in part due to the social ("gossipy") nature of posted comments. Similarly, users remember Facebook posts significantly better than sentences from a book or even human faces, on the same scale as the memory difference between amnesics and non-amnesics.

A meta-analysis of several dozen research studies indicates that higher levels of switching between different media channels is significantly linked to lower levels of both working memory and long-term memory. Given the current Extractive Attention Economy, and the increasing number of social media platforms and apps competing to capture our attention, basic human capacities - such as our memories - are increasingly under attack.

Physical and Mental Health

Stress, loneliness, feelings of addiction, and increased risky health behavior

Evidence

of 18-44 year olds feel anxious if they haven't checked Facebook in the last 2 hours, according to a recent survey of over 2,000 American adults that indicates a high incidence of potential Facebook addiction warning signs. In fact, many are so hooked that 31% report checking it while driving and 16% while making love.

away from Facebook leads to a significant improvement in emotional well-being. In an experimental study of over 1,600 American adults (who normally used Facebook for up to an hour each day), deactivating Facebook accounts led to a significant increase in emotional well-being (including a reduction in loneliness and an increase in happiness), as well as a significant reduction in political polarization.

Social Relationships

Less empathy, more confusion and misinterpretation

Evidence

Politics and Elections

Propaganda, distorted dialogue & a disrupted democratic process

Evidence

pieces of disinformation were slipping through daily on Facebook and less than 5% of hate speech was being deleted, a few weeks ahead of the Capitol attacks, according to staff leaving the company. Raising this and similar issues, at least 4 members of Facebook's integrity team resigned between May and December 2020, stating "it's an embarrassment to work here".

Spaniards are estimated to have received disinformation and hate speech via WhatsApp ahead of the 2019 national elections, with WhatsApp delivering more disinformation and hate speech than Twitter, YouTube, & Instagram combined, and almost as much as that spread by Facebook.

Americans were reached by Russian propaganda posts on Facebook during the 2016 US elections, according to Facebook's estimates.

Systemic Oppression

Amplification of racism, sexism, homophobia and ableism

Evidence

of the most shared Facebook posts about Black Lives Matter in June 2020 were critical of the movement, despite the fact that the majority of Americans support BLM, according to research by data analysis company CrowdTangle. Such fake representations of public opinion can play a significant role in distorting the basis for democratic dialogue and diminishing the momentum for social change. Even as societies take action to challenge racism and other forms of systemic oppression, social media platforms are being hijacked to discourage or even deny change.

Twitter users were actively involved in Gamergate at its peak, with the hashtag #Gamergate being tweeted hundreds of thousands of times per month, mostly supporting the campaign of abuse and violent threats against specific female game designers and those who spoke up to support them. Gamergate played out primarily on Twitter, whose platform design and administration, according to researchers, make the platform particularly adaptable for online abuse- due to the highly public nature of tweets, the potential for mass targeting of individuals, and the fact that abusive responses can't be removed.

Do Unto Others

Many people who work for tech companies - and even the CEOs - limit tech usage in their own homes

Evidence

WOULD YOU RECOMMEND THIS LEDGER TO A FRIEND OR COLLEAGUE? YES NO

Have a study, article, or correction to contribute?

The goal of the Ledger of Harms is to list compelling studies and articles that show clear effects, documented by relatively unbiased researchers and writers. If there's a key study or article missing, or if you see methodological problems with anything listed here, please let us know via the link below. We will update this page if the new information passes our review process.

Send Us Your Thoughts ↗

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From developmental delays to suicide, children face a host of physical, mental and social challenges Evidence Misinformation, conspiracy theories, and fake news Evidence Loss of crucial abilities including memory and focus The level of social media use on a given day is linked to a significant correlated increase in memory failure the next day.

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Turn off all notifications except from people.

Notifications appear in RED dots because red is a trigger color that instantly draws our attention. But most notifications are generated by machines, not actual people. They keep our phones vibrating to lure us back into apps we don't reallyneed to be in.

Visit Settings> Notificationsand turn off all notifications, banners, and badges, except from apps where real people want your attention; e.g. messaging apps like WhatsApp, FB Messenger, Signal, Telegram, WeChat etc.

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Take Control - Center for Humane Technology

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Notifications appear in RED dots because red is a trigger color that instantly draws our attention. But most notifications are generated by machines, not actual people. They keep our phones vibrating to lure us back into apps we don't reallyneed to be in.

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EU Kids Online coordinates and stimulates investigation into the way children use new media, with a particular focus on evidence about the conditions that shape online risk and safety. EU Kids Online recent research findings, methods and recommendations

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Recent Projects - Information Visualization

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Big Data explained (explainity® explainer video)

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Making a TED-Ed Lesson: Visualizing big ideas

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Exploration on the Big Data frontier - Tim Smith

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View full lesson: http://ed.ted.com/lessons/exploration-on-the-big-data-frontier-tim-smith There is a mind-boggling amount of data floating around our society. Physicists at CERN have been pondering how to store and share their ever more massive data for decades - stimulating globalization of the internet along the way, whilst 'solving' their big data problem.

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More than a decade ago, climate scientists and energy modellers made a choice about how to describe the effects of emissions on Earth's future climate. That choice has had unintended consequences which today are hotly debated. With the Sixth Assessment Report (AR6) from the Intergovernmental Panel on Climate Change (IPCC) moving into its final stages in 2020, there is now a rare opportunity to reboot.

In the lead-up to the 2014 IPCC Fifth Assessment Report (AR5), researchers developed four scenarios for what might happen to greenhouse-gas emissions and climate warming by 2100. They gave these scenarios a catchy title: Representative Concentration Pathways (RCPs). One describes a world in which global warming is kept well below 2 °C relative to pre-industrial temperatures (as nations later pledged to do under the Paris climate agreement in 2015); it is called RCP2.6. Another paints a dystopian future that is fossil-fuel intensive and excludes any climate mitigation policies, leading to nearly 5 °C of warming by the end of the century,. That one is named RCP8.5.

RCP8.5 was intended to explore an unlikely high-risk future. But it has been widely used by some experts, policymakers and the media as something else entirely: as a likely 'business as usual' outcome. A sizeable portion of the literature on climate impacts refers to RCP8.5 as business as usual, implying that it is probable in the absence of stringent climate mitigation. The media then often amplifies this message, sometimes without communicating the nuances. This results in further confusion regarding probable emissions outcomes, because many climate researchers are not familiar with the details of these scenarios in the energy-modelling literature.

This is particularly problematic when the worst-case scenario is contrasted with the most optimistic one, especially in high-profile scholarly work. This includes studies by the IPCC, such as AR5 and last year's special report on the impact of climate change on the ocean and cryosphere. The focus becomes the extremes, rather than the multitude of more likely pathways in between.

Happily - and that's a word we climatologists rarely get to use - the world imagined in RCP8.5 is one that, in our view, becomes increasingly implausible with every passing year. Emission pathways to get to RCP8.5 generally require an unprecedented fivefold increase in coal use by the end of the century, an amount larger than some estimates of recoverable coal reserves. It is thought that global coal use peaked in 2013, and although increases are still possible, many energy forecasts expect it to flatline over the next few decades. Furthermore, the falling cost of clean energy sources is a trend that is unlikely to reverse, even in the absence of new climate policies.

Assessment of current policies suggests that the world is on course for around 3 °C of warming above pre-industrial levels by the end of the century - still a catastrophic outcome, but a long way from 5 °C,. We cannot settle for 3 °C; nor should we dismiss progress.

Plan for progress

Some researchers argue that RCP8.5 could be more likely than was originally proposed. This is because some important feedback effects - such as the release of greenhouse gases from thawing permafrost, - might be much larger than has been estimated by current climate models. These researchers point out that current emissions are in line with such a worst-case scenario. Yet, in our view, reports of emissions over the past decade suggest that they are actually closer to those in the median scenarios. We contend that these critics are looking at the extremes and assuming that all the dice are loaded with the worst outcomes.

Asking 'what's the worst that could happen?' is a helpful exercise. It flags potential risks that emerge only at the extremes. RCP8.5 was a useful way to benchmark climate models over an extended period of time, by keeping future scenarios consistent. Perhaps it is for these reasons that the climate-modelling community suggested RCP8.5 "should be considered the highest priority".

We must all - from physical scientists and climate-impact modellers to communicators and policymakers - stop presenting the worst-case scenario as the most likely one. Overstating the likelihood of extreme climate impacts can make mitigation seem harder than it actually is. This could lead to defeatism, because the problem is perceived as being out of control and unsolvable. Pressingly, it might result in poor planning, whereas a more realistic range of baseline scenarios will strengthen the assessment of climate risk.

This admission does not make climate action less urgent. The need to limit warming to 1.5 °C, as made clear in the IPCC's 2018 special report, does not depend on having a 5 °C counterpoint.

Assess realistically

The plethora of future emissions scenarios poses a challenge to users of climate data - from policymakers to investors. More than 1,200 mitigation scenarios were assessed in AR5 in 2014. Another 400 scenarios were used in the IPCC's 2018 special report on 1.5 °C of warming. Most of these assume a baseline with no climate policy across a range of socio-economic developments. In our experience of working with scenario users, this proliferation leads to more confusion than clarity, particularly in the absence of any guidance on the relative likelihood of each scenario.

Other organizations present relatively few scenarios - the International Energy Agency (IEA), for example, now has just three main ones. Its Current Policies Scenario indicates what could happen to emissions with things as they stand. The Stated Policies Scenario includes current policy intentions and targets. The IEA's Sustainable Development Scenario reflects emissions in a world that is already aligned with the goals set in Paris. The United Nations Environment Programme's Emissions Gap Report takes a similar approach, comparing countries' emissions-reduction pledges with global pathways that limit warming to well below 2 °C. These influential agencies do not focus on worst-case outcomes. They plot the gulf between where the world is heading and where it has agreed it should go.

For those making real-life decisions, the choice of scenario becomes important,. Emphasizing ways of adapting to an extreme RCP8.5 scenario with around 5 °C warming in 2100 is out of step with the requirement to build resilience and reduce vulnerabilities in the near-term. Most users of climate scenarios care more about the world as it is now, rather than what might have been had global emissions not slowed over the past decade. Users focused on mitigation are keen to capitalize on emerging opportunities such as cheap renewables, or to avoid overinvesting in stranded assets in dying industries. For example, they want to know whether the rapid cost declines in renewables might make investments in fossil fuels high risk. A RCP8.5 baseline renders these applications useless, because it implies that recent climate policies and technological progress are halted or even reversed.

For policymakers, mitigation policies that depend on the assumptions underlying high-emission baseline scenarios such as RCP8.5 will seem exorbitant, because they do not incorporate the plummeting costs of many low-carbon technologies over the past decade. The marginal investments required to move from 3 °C of warming to well below 2 °C (the main Paris goal) will be much less than moving from 5 °C to well below 2 °C. A narrative of progress and opportunity can make the Paris targets seem feasible, rather than seemingly impossible.

Towards risk-based scenarios

Those who are tasked with taking climate action on the basis of information from model scenarios are increasingly calling for a more risk-based approach to help with adaptation and mitigation. This approach accounts for the relative likelihood of different outcomes. Controversially, it requires researchers to assign probabilities to scenarios. Critics don't want to do this, because many see it as an arbitrary process. But when specialists refuse to assign probabilities, users often do so themselves. Most do so poorly because they do not have a deep understanding of the assumptions that underpin these scenarios.

Initially, the probabilities do not need to be elaborate, and could even just identify the most likely scenario resulting from current energy-system trends and policies. Now, scenarios are selected on the basis of their climate outcomes in 2100, not their likelihoods. More complex probabilistic approaches would require modellers to work differently. For example, they would need to forge new alliances with those in the social sciences and involve policymakers, investors and industry.

This will require years of work. Meanwhile, three steps should be taken over the next year in the lead-up to AR6, to set the climate community on the right road. The latest generation of climate models has just come out, and many researchers are now selecting which future emissions scenarios to use in studies.

First, the new generation of scenarios called the Shared Socioeconomic Pathways (SSPs; see 'Parting of the pathways') has a much more nuanced approach to baselines, and IPCC authors can highlight a range of outcomes in a world with no new policies (see also Nature Clim. Change 9, 727; 2019). The space between high-end and low-end scenarios should be more deeply explored in AR6, so that the climate impacts we are likely to experience can be communicated more clearly. For example, according to many studies, we are heading for a 3 °C world. Therefore, it would be prudent to clearly outline the climate impacts for 3 °C in addition to those for 5 °C.

Parting of the pathways

Second, scientists should recognize that different users need different tools. In the context of AR6, this could mean that the various working groups (focusing on climate science, impacts and mitigation) highlight different scenarios in their analyses and communications. The final AR6 synthesis could then integrate the different risk perspectives.

Finally, we suggest that climate-impact studies using models developed for AR6 should include scenarios that reflect more-plausible outcomes, such as SSP2-4.5, SSP4-6.0 and SSP3-7.0 (see 'Possible futures'). When RCP8.5 or its successor SSP5-8.5 are deployed, they should be clearly labelled as unlikely worst cases rather than as business as usual.

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Emissions - the 'business as usual' story is misleading

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Stop using the worst-case scenario for climate warming as the most likely outcome - more-realistic baselines make for better policy. Stop using the worst-case scenario for climate warming as the most likely outcome - more-realistic baselines make for better policy.

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Social media platforms are central to every aspect of teens' lives, from how they stay in touch with friends to how they engage with politics. And constantly refreshing their social feeds can feel simultaneously positive and negative: Teens say social media strengthens their relationships but also distracts them from in-person connection.

Social Media, Social Life: Teens Reveal Their Experiences sheds light on teens' changing social media habits and why some kids are more deeply affected by -- and connected to -- their digital worlds. The report is a nationally representative survey of more than 1,000 kids age 13 to 17. And because it tracks changes from 2012 to today, we can see how teens' social media use continues to evolve. Read the full report

When it comes to social media, teens have always been ahead of the curve. Families, teachers, advocates, and content creators looking to keep up can get started with these Common Sense tips and tools:

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Social Media, Social Life: Teens Reveal Their Experiences (2018) | Common Sense Media

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Teens use media in unexpected and meaningful ways. This report surveys young people about how social media affects their social and emotional well-being, for better or worse, and explores the major changes and trends in social media use since 2012.

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Common Sense is the nation's leading nonprofit organization dedicated to improving the lives of all kids and families by providing the trustworthy information, education, and independent voice they need to thrive in the 21st century.