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URL: https://www.mdpi.com/1660-4601/20/12/6132

TITLE: Riverine Microplastic Pollution: Insights from Cagayan de Oro River, Philippines.

AUTHOR: Aiza D. Gabriel

DATE PUBLISHED: June 15, 2023

KEY POINTS: Provides a comprehensive examination of microplastic pollution in the Cagayan de Oro River, including detailed methodologies for sampling, extraction, and analysis, which contribute to a better understanding of the extent and nature of microplastic contamination in freshwater ecosystems.

Philippines

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Environmental Science Graduate Program, Department of Biological Sciences, Mindanao State University-Iligan Institute of Technology (MSU-IIT), Tibanga, Iligan City 9200, Philippines

Premier Research Institute of Science and Mathematics, Mindanao State University-Iligan Institute of Technology (MSU-IIT), Tibanga, Iligan City 9200, Philippines

Department of Chemical Engineering and Technology, Mindanao State University-Iligan Institute of Technology (MSU-IIT), Tibanga, Iligan City 9200, Philippines

Environmental Pollution and Innovation Laboratory, Center for Sustainable Polymers, Mindanao State University-Iligan Institute of Technology (MSU-IIT), Tibanga, Iligan City 9200, Philippines

Author to whom correspondence should be addressed.

1. Introduction

Plastics advance several societal sectors and improve our quality of life due to their various uses. These include packaging, coatings, adhesives, fabrics, transportation, construction, biomedicine, organic electronics, and nanotechnology [ 1, 2]. Plastic production continues to increase due to its low density, strength, user-friendly design, fabrication capabilities, and, most importantly, low cost [ 3, 4, 5]. In addition, the plastic industry has a vital part to play in attaining the Sustainable Development Goals (SDGs) since it generates thousands of job opportunities essential to combatting extreme poverty (SDG 1), which can also impact the other SDGs [ 6]. However, despite their advantages, plastics are often treated only as disposable commodities, which comes with a significant drawback: waste accumulation [ 2, 6].

When managed appropriately, freshwater ecosystems offer essential ecosystem services to humans such as fish production, water supply, nutrient transport, and recreational value [ 7, 8]. Though the planet comprises about 70% water, only 2.5% is freshwater [ 9, 10]. Freshwater resources on our planet are sparse, but they are, nonetheless, in danger of contamination. According to the United Nations Environment Programme (UNEP), freshwater pollution comes from various sources: power generation, heavy industry, automobiles, municipal, industrial, agricultural, wastewater, fertilizer runoff, and others. Freshwater and marine ecosystems share many similar causes of plastic pollution, including inefficient waste management and improper disposal from residential, industrial, and farming practices, generating plastics that will eventually end up in lakes, rivers, and streams [ 11]. Additionally, most marine plastics are presumed to be transferred from the land to the ocean via rivers [ 12, 13, 14]; however, the plastic pollution in the riverine system in the Philippines is poorly documented.

Cagayan de Oro City is a first-class, highly urbanized city in Northern Mindanao, Philippines. It is undergoing rapid commercial, residential, and industrial expansion and is considered an economic hotspot that links agro-based products of neighboring provinces to the country's central economic institutions in metropolitan cities such as Manila, Cebu, and even abroad [ 67]. It has a total population of 728,402, with a growth rate of 1.58% (2020 Census of Population and Housing). The Cagayan de Oro River, the study's focus, is known as the "Whitewater Rafting Capital in the Philippines" since it offers year-round rafting, making it more popular with tourists. It has enormous economic and environmental significance and potential as it serves as a water supply for domestic, industrial, agricultural settings, and for hydroelectric power generation [ 68]. However, it is also one of five river systems that the country's Department of Environment and Natural Resources-Environment Management Bureau (DENR-EMB) has identified as biologically threatened [ 69]. Based on the study undertaken by Meijer et al. [ 70], the Cagayan de Oro River ranked 32 nd (3.6 × 10 ³ metric tons/year) of the top 50 plastic-emitting rivers into the ocean globally. Exposed plastics may degrade into microplastics, and the fact that people who lived close to rivers rely on river life forms, including fish, snails, and plants, for sustenance and household consumption [ 71] makes it more alarming, highlighting the dire need for this study. However, the extent of microplastic pollution in this ecologically important river has not been systematically studied yet.

In this study, we hypothesized that the lowest microplastic concentrations would be relatively low upstream of the Cagayan de Oro River and higher downstream due to increasing anthropogenic activities. To test this hypothesis, we investigated the abundance, concentration, and distribution of microplastics in the surface water of the Cagayan de Oro River. Specifically, this study aimed to: (a) quantify the microplastic concentrations at the six sampling stations along the Cagayan de Oro River; and (b) determine the color, shape, size, and polymer types of microplastics in the Cagayan de Oro River.

2. Materials and Methods

This study was conducted along the Cagayan de Oro River, located in Northern Mindanao. It is part of a river system that drains into the northern central part of Mindanao. The river's headwaters are situated in the Kalatungan Mountain Range, which is in the central part of the province of Bukidnon [ 69, 72]. It traverses through Talakag, Baungon, and Libona municipalities, filling up tributaries. It finally drains into Macajalar Bay at Cagayan de Oro City in the province of Misamis Oriental [ 69].

2.1. Sampling

This study established six sampling stations, with three sampling points in each station perpendicular to the river channel ( Figure 1, Table 1). Two sampling points were established separately within five meters of the riverbanks and one point at the center. Stations 1, 2, and 3 (S1-S3) were established at barangay Macasandig with 3743/km ² population density, Station 4 (S4) at barangay Nazareth with 10,002/km ² population density, Station 5 (S5) at barangay Kauswagan with 8167/km ² population density, and Station 6 (S6) at barangay Puntod with 13,412/km ² population density. Barangay Puntod has the highest population density while barangay Macasandig has the lowest. From upstream (S1) to downstream (S6), each station was situated around 1.9 km apart ( Figure 1).

We used an inflatable boat to travel to every station. Surface water samples were collected on 15 December 2022, following the methods of Osorio et al. [ 62] with minor modifications, such as increasing the number of sampling points from one sampling point to three and using a 0.3-mm metal sieve instead of different sizes. Three water samples were collected at each station since there may be variations in microplastic concentration across the channel [ 73]. A total of 180 L (0.18 m ³) of water samples were collected across all stations using a stainless steel bucket [ 62, 74], and taking a 10 L (0.01 m ³) sample from each point at a depth of up to 50 cm. The samples were immediately sieved through a 0.3-mm metal sieve and rinsed with distilled water while being collected in a labeled glass bottle [ 75, 76]. The mouths of the glass bottles were covered with aluminum foil before being sealed with a cap to limit light exposure and contamination. Water samples secured in an ice box were carried to the laboratory and kept in the dark pending further analysis.

2.2. Microplastic Extraction and Identification

The sieved samples were placed in a beaker and 10% KOH was added, twice the sample's volume, to digest the organic matter. The samples were heated to 60 °C for 24 h in the oven. After digestion, the supernatant liquid was vacuum filtered using a 40 mm diameter Whatman GF/C glass filter. The remaining sample with solids underwent density separation for at least 2 h to float the less dense microplastics by adding 30% NaCl solution, twice the volume of the remaining sample. The supernatant carrying microplastics was vacuum filtered again using a Whatman GF/C glass filter. All filter papers used during vacuum filtration were placed in a clean petri dish and dried. The dried filter papers were visually inspected using a stereomicroscope (40× magnification) to classify the suspected microplastics according to color and shape under the criteria set by previous research [ 77, 78]. The suspected microplastics were mounted in between two clean and labeled glass slides using a clean needle and measured afterward. Similar to the method employed by Abidli et al. [ 79] and Toumi et al. [ 80], a stereomicroscope with calibrated ocular micrometer was used to measure the size of the suspected microplastics. After microscopy, the suspected microplastics were subjected to Fourier transform infrared spectroscopy (FTIR) analysis (Shimadzu IRTracer-100) to classify polymer type. This method is the most cost-effective way to obtain information regarding particle quantities, polymer types, and sizes [ 81]. According to Tirkey and Upadhyay [ 82], FTIR is possibly the best technique for chemical characterization aside from Raman spectroscopy. Compared to Raman spectroscopy with a lower detection threshold (down to 1 μm), FTIR is less time-consuming [ 81, 83]. Additionally, the FTIR method is accurate, does not damage the samples, and produces spectra; however, it has a limited detection threshold that is only feasible for particles up to 20 μm.

2.3. Quality Control

Before proper laboratory work, we ensured the laboratory glassware was thoroughly washed and rinsed with distilled water to remove contaminants. Every sample preparation process involved including one control group to confirm the validity of the data collected. Background contamination in the air was also tested through wet filter paper in a petri dish, and no contamination occurred.

2.4. Data Analysis

The microplastic concentration was expressed in items per m ³. The data were first tested with a normality test using the Shapiro-Wilk test. One-way analysis of variance (ANOVA) was used to determine if significant differences were present at the six sampling stations. Tukey's test for pairwise mean comparisons was used after testing for significance in the ANOVA test at the 95% significance level. Statistical analyses were employed using the PAST software version 4.12b.

3. Results

All six sampling stations were contaminated with microplastics, which varied in abundance ( Table 1). From a total of 90 suspected microplastics that were extracted, 54 (60%) were confirmed to be microplastics after FTIR analysis. Across all the stations, we recorded a mean concentration of 300 items/m ³ MPs in the surface water of the Cagayan de Oro River. The highest number of MPs with 18 items was at S6, which was close to the mouth of the river, followed by S5 with 17 items, S2 with eight items, S1 with six items, S4 with three items, while the lowest was at S3 (middle) with two items ( Table 1). No pattern was observed across all the stations, but it is still evident that the downstream has three times more MPs than were found in the upstream. Figure 2 shows images of the microplastics extracted from the Cagayan de Oro River, along with the stations where they were taken and their sizes. The highest concentration of MPs was detected at S6 (600 ± 57.74 items/m ³) in barangay Puntod, located downstream near Macajalar Bay. At the station, we observed several pump boats that people use for their livelihood for fishing and transportation, suggesting more anthropogenic activities in the area. Station 6 was situated between two barangays that were connected by a path made possible by the use of pump boats. The second highest concentration was found at S5, located in barangay Kauswagan with 566.7 ± 83.89 items/m ³, followed by S2 located in barangay Macasandig with 266.7 ± 50.92 items/m ³, S1 located also in barangay Macasandig with 200 ± 66.67 items/m ³, and S4 located in barangay Nazareth with 100 ± 57.74 items/m ³. Meanwhile, the lowest concentration of MPs was found at S3 (middle), located in barangay Macasandig, with 66.7 ± 19.25 items/m ³. Station 3 was observed to have only a few settlements near the river and was not accessible compared to the other stations. One-way analysis of variance (ANOVA) showed a significant difference (p < 0.05) present at the six sampling stations along the Cagayan de Oro River, Philippines. Through the Tukey test (p < 0.05), we confirmed that S5 (566.7 ± 83.89 items/m ³) and S6 (600 ± 57.74 items/m ³) were significantly higher than S3 (66.7 ± 19.25 items/m ³) and also S6 (600 ± 57.74 items/m ³) was significantly higher compared to S4 (100 ± 57.74 items/m ³). Conversely, there is no significant difference between S6 and S1; however, it is observed that S6 has three times more MP concentration compared to S1, suggesting that there are more MPs downstream than upstream.

Extracted MPs were documented and classified based on color, shape, size, and polymer types. As shown in Figure 3, dominant MPs in the Cagayan de Oro River based on the four properties are blue-colored (59%), fiber (63%), 0.3-0.5 mm (44%), and polyacetylene (48%). Blue-colored MP has the highest concentration of 177.8 items/m ³, accounting for 59% of the total MPs. Red-colored MP has the second highest concentration of 44.4 items/m ³, accounting for 15% of the total MPs, and is comparable to white-colored MPs with 33.3 items/m ³, accounting for 11% of the total MPs. Transparent and brown-colored MPs are comparable, with concentrations of 22.2 items/m ³ (7%) and 16.7 items/m ³ (6%), respectively. The lowest concentration is black-colored MPs, with only 5.6 items/m ³ accounting for 2% of the total MPs. We observed that blue and red MPs were present at all stations. Conversely, black-colored MPs were only observed at S1.

Figure 3B and Figure 4B show that fibers have the highest concentration, totaling 188.9 items/m ³ and accounting for 63% of the total MPs. The filament has the second highest concentration, with 77.8 items/m ³ accounting for 26% of the total. In addition, the filament is about two times more than the lowest concentration, fragment (33.3 items/m ³), accounting for 11% of the total MPs. Microplastics were also classified into four size fractions: 0.3-0.5 mm, 0.5-1.0 mm, 1.0-2.5, and 2.5-5.0 mm ( Figure 3C and Figure 4C). The most prevalent sizes were 0.3-0.5 mm with 133.3 items/m ³ accounting for 44%, followed by 1.0-2.5 mm with 77.8 items/m ³ (26%), 0.5-1.0 mm with 66.7 items/m ³ (22%), and 2.5-5.0 mm with 22.2 items/m ³ (7%). On the other hand, FTIR results confirmed five polymer types in this study: polyacetylene, polyester, polyurethane, polyethylene terephthalate, and polyamide ( Figure 5). Their concentrations are 144.4 items/m ³, 105.6 items/m ³, 38.9 items/m ³, 5.6 items/m ³, and 5.6 items/m ³, accounting for 48%, 35%, 13%, 2%, and 2%, respectively. Polyacetylene has the highest concentration found present at all sampling stations. Polyester has the second highest concentration and was also present at all stations. On the other hand, polyurethane was only identified at S1 and S6, while polyethylene terephthalate and polyamide were only identified at S5.

4. Discussion

We identified that the microplastic concentrations at S6 and S5, located downstream near the mouth of the river, were significantly higher than at S3, which was situated in the middle, and S6 was also significantly higher than S4. There was no significant difference between S6 and S1; however, S6 (downstream) had three times more microplastic than S1 (upstream). The results were similar to the study conducted by Tang et al. [ 84] in the Songhua River, China, and Buwono et al. [ 85] in the Brantas River, Indonesia, which also observed that there were higher microplastic concentrations downstream than upstream due to human interference and possible accumulation at the river mouth. Moreover, according to Requiron and Bacosa [ 35], the closer the sampling point is to the river mouth, the higher the possibility of accumulating plastic litter.

We also observed that the accumulation of microplastic is related to population density since S6, located in barangay Puntod with the highest population density, also has the highest microplastic concentration. In contrast, S3, located in barangay Macasandig with the lowest population density, accumulates the lowest microplastic concentration. Based on the study conducted by Ta and Babel [ 86], there is a direct correlation between population density and microplastic abundance in the river. In relation to this, anthropogenic activities are closely related to microplastic contamination [ 87]. At S6, a residential area, the river portion is used for various purposes, including fishing and transportation via pump boat to nearby barangays. Conversely, S3, a non-residential area, has no intensive anthropogenic activities observed.

Compared to other studies, the mean concentration in the Cagayan de Oro River, which is 300 items/m ³, is considered the lowest among the rivers documented in the Philippines ( Table 2). It is also expected since the Pasig River, Parañaque River, Meycauayan River, and Tullahan River were listed as top plastic emitters based on the study conducted by Meijer et al. [ 27]. Compared to other rivers in China, our study is higher than the study conducted by Mai et al. [ 88] at the Pearl River Delta and lower than that of Lin et al. [ 89] along the Pearl River. These variations may be due to methodological approach differences, such as using different mesh or pore sizes during sample collection. Smaller mesh or pore size can collect smaller plastic particles, thereby higher microplastic concentration. In this study, we used a 0.3 mm mesh sieve. In comparison with the other studies with similar mesh or pore sizes, such as the studies conducted along the Gave de Pau River (France), the Surabaya River (Indonesia), the Ofanta River (Italy), and the Pearl Delta River (China), the Cagayan de Oro River has the highest microplastic concentration suggesting regional variation depending on plastic emissions.

Extracted microplastics were classified based on color, shape, size, and polymer type. These properties are potentially relevant to their ecotoxicity; however, changes still depend on environmental conditions and degradation pathways [ 94].

In terms of shape, the Cagayan de Oro River, Philippines, was dominated by fiber MPs, similar to the study conducted along the Pearl River, China, which accounted for 94.4% of the total [ 89]. In addition, microplastic studies in the Philippines such as the study undertaken by Arcadio et al. [ 60] in Laguna de Bay, Navarro et al. [ 63] in Butuan Bay, and Sajorne et al. [ 30] on Puerto Princesa Beach, Palawan were all dominated by fiber MPs. One of the causes of the release of fiber MP is washing a garment that can shed more than 1900 fibers per wash, releasing more than 100 fibers per liter of effluent [ 55]. Fish cages, fishing equipment, and nylon rope deterioration are also significant sources of MP fibers [ 96]. Studies have shown several negative impacts of MP fibers on aquatic organisms, such as tissue damage, reduced growth, severe intestinal toxicity, and even mortality [ 103, 104]. This can lead to a reduced fish catch, affecting the livelihoods of the local populations, or worse, microplastic-contaminated fish could be eaten by humans.

The most dominant size range of MPs found in the Cagayan de Oro River, Philippines was 0.3-0.5 mm. This is comparable to the study conducted by Faulstich et al. [ 105] in the sediments of the Namibian River, Namibia where this size range comprised 33.7% of the total MPs. In addition, the study conducted in the Tamsui River also identified 0.3-5 mm size range particles [ 106]. Different size ranges of MPs represent different pathways for MP exposure and impacts on organisms [ 107].

Polyacetylene was present at all six sampling stations established in the study area. Recent studies also found polyacetylene in rivers and other environments [ 108, 109, 110, 111]. It is a conductive polymer that is used as a doping agent for manufacturing various electronic devices due to its thin and stretchable characteristics [ 112]. Polyester, found in the second-highest level of abundance in the study, was also found at all stations. During the fieldwork, we observed locals washing their clothes in the river. It can be attributed to the presence of polyester since previous research revealed that even delicate hand washing of clothes releases microfiber polyester [ 113].

Aside from anthropogenic activities, variations in levels of microplastics may be affected by other factors. The previous study confirmed that rainfall significantly increased microplastic concentration [ 114]. Days before our sampling, rainfall occurred, possibly affecting the MP concentration in the area, and this needs further investigation. Aside from that, hydrodynamic conditions significantly affected the microplastic distribution through the construction of water conservancy hubs and changes in the river's width [ 115]. We noticed a higher MP concentration at the stations with wider river widths and vice versa.

5. Conclusions

Our study revealed that all six sampling stations along the Cagayan de Oro River, Philippines, were contaminated with microplastics. Higher MP concentrations were observed at Station 6, located downstream near Macajalar Bay, compared to stations found upstream and midstream. Aside from the anthropogenic activities, we also observed that river width affects MPs concentration. The largest river width was identified as having the highest concentration of MPs and vice versa. This study imparts the first documented evidence of the abundance, distribution, and composition of microplastics in the surface water of the Cagayan de Oro River, Philippines, and the first among the rivers in Mindanao, the second largest island in the Philippines. The river is an essential resource for humans and aquatic organisms. Determining pollutants such as microplastics or having baseline data such as documented in the current study will help in achieving the Sustainable Development Goal (SDG) 6, or clean water and sanitation, by informing people, especially policymakers and stakeholders, to take immediate action. This data will help them create new prevention strategies or update existing policies guided by scientific evidence. Furthermore, re-evaluation and stringent enforcement of plastic legislation and the imposition of fines for illegal dumping are encouraged to minimize plastic accumulation, plastic degradation, and detrimental effects on aquatic organisms as well as on humans. Aside from immediate action by policymakers and stakeholders, residents may help address the increasing plastic waste problem by using biodegradable alternatives to plastics and adhering to basic waste management and disposal practices. Adherence to plastic ordinances, such as the recently passed "Single-Use Plastic Ban", to prevent additional plastic being transported to rivers and other aquatic environments will be highly beneficial.

Author Contributions

Conceptualization, A.D.G. and H.P.B.; methodology, A.D.G., A.A.L. and H.P.B.; software, A.D.G. and H.P.B.; validation, H.P.B., A.A.L. and R.F.A.J.; formal analysis, A.D.G.; investigation, A.D.G. and H.P.B.; resources, A.D.G., A.A.L. and H.P.B.; data curation, A.D.G.; writing-original draft preparation, A.D.G.; writing-review and editing, H.P.B. and R.F.A.J.; visualization, A.D.G. and H.P.B.; supervision, H.P.B., A.A.L. and R.F.A.J. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the Department of Science and Technology-Accelerated Science and Technology Human Resource Development Program.

Institutional Review Board Statement

Informed Consent Statement

Data Availability Statement

Acknowledgments

The first author would like to acknowledge the support from the Department of Science and Technology through the Accelerated Science and Technology Human Resource Development Program (ASTHRDP) scholarship program. We thank Rey Capangpangan, Sherley Ann Inocente, and Joanna Mea Celmar for their input and suggestions. We also thank the Center for Sustainable Polymers, Mindanao State University-Iligan Institute of Technology for the assistance in analyzing the samples' polymer type.

Conflicts of Interest

The authors declare no conflict of interest.

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Figure 1. Map of Cagayan de Oro City, Philippines showing the six sampling stations along the Cagayan de Oro River from upstream (S1) to downstream (S6).

Table 1. Geographical coordinates and characteristics of sampling stations along the Cagayan de Oro River, Philippines, with the number of microplastics and their mean concentration.

Table 2. Comparison of microplastic concentration in the Cagayan de Oro River compared to other rivers in the Philippines and those in other countries.

Gabriel AD, Amparado RF Jr., Lubguban AA, Bacosa HP. Riverine Microplastic Pollution: Insights from Cagayan de Oro River, Philippines. International Journal of Environmental Research and Public Health. 2023; 20(12):6132. https://doi.org/10.3390/ijerph20126132

Chicago/Turabian Style

Gabriel, Aiza D., Ruben F. Amparado, Jr., Arnold A. Lubguban, and Hernando P. Bacosa. 2023. "Riverine Microplastic Pollution: Insights from Cagayan de Oro River, Philippines" International Journal of Environmental Research and Public Health 20, no. 12: 6132. https://doi.org/10.3390/ijerph20126132

# data[].attributes.attachment_link.title
Riverine Microplastic Pollution: Insights from Cagayan de Oro River, Philippines

# data[].attributes.attachment_link.description
Rivers are vital water sources for humans and homes for aquatic organisms. Conversely, they are well known as the route of plastics into the ocean. Despite being the world's number one emitter of riverine plastics into the ocean, microplastics (MPs), or plastic particles less than 5 mm, in the Philippines' rivers are relatively unexplored.

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URL: https://www.sunstar.com.ph/amp/story/davao/local-news/oceans-silent-threat

TITLE: Ocean’s silent threat

AUTHOR: David Ezra M. Francisquete

DATE PUHBLSIHED: 9th Dec, 2023 at 11:15 AM

KEYPOINTS: Abandoned fishing gears such as fishing nets are a threat to marine biodiversity especially to coral reefs.

# data[].attributes.attachment_link.readable_text
Despite decades of grappling with this environmental issue and recognizing its silent menace to our present and future, collective actions have remained elusive.

Debates persist over whether plastics are truly responsible for the demise of maritime fauna.
ALARMING STATS
A joint report from the Food and Agriculture Organization and the United Nations Environment Program (Unep) estimates that approximately 640,000 tons of these abandoned materials are strewn across oceanic life, accounting for 10% of oceanic litter.

4Ocean reports alarming statistics, indicating that each year, around 1,144 mi2 (2,963 km2) of gill nets, roughly the size of Rhode Island, are lost at sea.

Additionally, an estimated 84 mi2 (218 km2) of trawl net, equivalent to the size of Guam, and about 115,540 mi2 (739,583 km2) of longline mainlines are lost-an expanse that, in physics terms, could allow one to travel to the moon and back.
LOCAL ACTION
On November 25, Davao Gulf Divers (DGD) and the Department of Environmental and Natural Resources-Protected Area Management Office (DENR-Pamo retrieved approximately 100 meters of net abandoned by fisherfolks in Punta-North, adjacent to the DGD Marine Park on Kopiat Island.

Davao Gulf, home to thriving corals and hydra coral reefs spanning 308,000 hectares, is a vital part of Mindanao's marine life, classified as one of the world's biodiversity hotspots.

Unfortunately, a 2006 report indicates that Davao Gulf's coral reefs have deteriorated significantly, disrupting the dynamic system and posing a threat to marine wildlife, including toothed whales, dolphins, whale sharks, sea cows, and endangered turtles.

SunStar Davao interviewed the Bureau of Fisheries and Aquatic Resources-Davao Region (Bfar-Davao Region) officer-in-charge Relly B. Garcia, who expressed gratitude for the report and emphasized the need for conservation and attention to Davao Gulf's coral reefs.

"Ito po ang unang ulat na natanggap ko simula ng aking panunungkulan bilang officer-in-charge regional director ng Bfar 11. Salamat for bringing this concern to our agency's attention. Davao Gulf is home to coral reefs that require conservation and proper attention, and we are looking into this matter (This marks the first report I've received since assuming the role of officer-in-charge regional director of Bfar 11. Thank you for highlighting this matter for our attention. The coral reefs in Davao Gulf demand conservation and proper consideration, and we are actively addressing this issue)," Garcia said.

In the Davao Region alone, there are 75 locally managed marine protected areas/fish sanctuaries covering 5,945.85 hectares with restricted fishing to manage, protect, and conserve marine resources. These areas face pollution, not only from plastics but also from fishing gear, making it challenging to identify perpetrators.
LEGAL GAPS
Bfar-Davao Region said that the Philippine Fisheries Code lacks specific provisions for abandoned fishing nets or gears, but stringent penalties exist for coral destruction and aquatic pollution.

"It is very important to educate the fishermen of the dangers of abandoning nets in the open ocean," Bfar-Davao said.

Unlike nets made from biodegradable materials in the past, modern synthetic materials like nylon can persist in the ocean for hundreds of years. When these gears break, marine life ingests plastic fragments, releasing toxins into the water.

Unlike other forms of plastic pollution, fishing gear is intentionally designed to harm fauna. While there are global laws addressing this, individual responsibility becomes paramount since there is no foolproof system to trace errant fishermen. DEF

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Learn about local conservation efforts and the legal gaps in addressing this silent menace. Dive into the urgent need for collective action to protect our oceans.

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RESEARCHED BY: CATAM-ISAN, VINCRYS AMBRUCE

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URL: https://www.gmanetwork.com/news/scitech/science/896175/microplastic-found-in-fish-from-mindanao-denr-asks-companies-to-address-issue/story/?amp

TITLE: Microplastics found in fish from Mindanao, DENR asks companies to address issue

AUTHOR: GMA Integrated News
DATE PUNLISHED: February 01, 2024 10:22 PM

KEY INFO: Microplastics are found in fishes that is from Mindanao.

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Traces of microplastic were found in several fish species, specifically bangus (milkfish), from different fishponds in Mindanao, a study by the Department of Science and Technology National Research Council of the Philippines (DOST-NRCP) showed.

According to Mark Salazar's 24 Oras report on Thursday, the study revealed that around 60% of the fish samples contained concentrations of microplastic in their digestive systems.

Microplastics are tiny particles produced from the degradation of plastic materials.

"Ang microplastics kasi, mas malaki ang epekto niya sa mas maliliit na organismo," said Dr. Deo Florence Onda, Microbial Oceanographer of Marine Science Institute.

(Microplastics have a large effect on smaller organisms.)

"Kung 'yung maliliit na isda ay naapektuhan at hindi na nila kayang lumaki dahil sa microplastics, anong mangyayari? Ano 'yung aanihin natin? Kulang pa rin tayo sa pag-aaral kung ano 'yung overall impact niya sa health ng tao," Onda said.

(If small fish consume microplastic it stunts their growth, what happens? What will our fishermen catch? There's also a lack of study on its overall impact on human health.)

Environment Secretary Maria Antonia Yulo-Loyzaga warned that microplastic pose a threat not only to the environment but also to the livelihood of fisherfolk.

"Nilalason po ng mga plastic na ito ang mga palaisdaan at tsino-choke po nila ang mga coral reefs natin. Dito po nanggagaling ang livelihood ng mga mangingisda natin at ang mga isda na kinakain po natin araw-araw. Ang mga isda po natin ay kumakain ng mga microplastic," said Yulo.

(Microplastics are poisoning the fishponds and choke our coral reefs. This is the source of livelihood of fisherfolk and the food we consume on a daily basis. Our fish have been eating microplastic.)

A major source of microplastic: the packaging of consumer goods that as trash eventually end up in sewage and later, the ocean.

The DENR head said over 140 million plastic sachets are in the country's waterways that eventually reach the sea.

In August 2022, a study revealed the Philippines as one of the leading countries that pollute the ocean.

To address the situation, Yulo called on major corporations to lead in the collection of plastic waste, with a target of collecting 80% of plastic waste by 2028.

"We are now implementing ang Extended Producers' Responsibility Law. Ano pong ibig sabihin niyan? Iyan po ay nagsi-shift burden na kumolekta ng plastic basura dito po sa mga korporasyon na nagpo-produce po ng plastic packaging," she said.

(We are now implementing ang Extended Producers' Responsibility Law. What does that mean? The collection of plastic wastes should be shouldered by corporations that produce plastic packaging.)

Dr. Onda said that there are studies predicting that there could be more plastic than fish in the world's oceans by 2050- an alarming projection for the future. -Sundy Locus/RF, GMA Integrated News

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Microplastics found in fish from Mindanao, DENR asks companies to address issue

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Microplastics were found in several fish species from Mindanao, a study by the Department of Science and Technology National Research Council of the Philippines (DOST-NRCP) showed.

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URL: https://creativemanila.com/dirty-watercolor-art-show/

TITLE: Dirty Watercolor

AHUTOR: TBWA SMP

DATE PUBLISHED: May 24, 2017

KEY POINTS: The ABS CBN Foundation, which cleans contaminated rivers in the Philippines, aimed to raise awareness to Manila's filthy tributaries, which were proclaimed dead during the Philippine International Rivers Summit in 2012.

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URL: https://www.nbcnews.com/news/world/whale-philippines-dies-88-pounds-plastic-stomach-n984421

TITLE: WHALE IN THE PHILIPPINES DIES WITH 88 POUNDS OF PLASTIC IN STOMACH

AUTHOR: Ben Kesslen

DATE PUBLISHED: March 19, 2019

KEY POINTS: Darrell Blatchley, director of the D' Bone Collector Museum, shows plastic waste found in the stomach of a beaked whale on the southern Philippine island of Mindanao on March 16, 2019.

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With millions of tons of plastic ending up in the world's oceans every year, it's not unusual for marine wildlife to ingest some of it.

But a museum in the southern Philippines said it made a stomach-churning discovery on Saturday when a beaked whale measuring more than 15 feet long was found dead with 88 pounds of plastic still lodged inside of it. The creature was located off the coast of the Mabini Campostela Valley.

"I was not prepared for the amount of plastic," Darrell Blatchley, president and founder of the D' Bone Collector Museum in Davao City, told NBC News in a statement.

The plastic included 16 rice sacks, four banana plantation bags and multiple shopping bags. It was the most plastic ever found by the group inside of a whale, said the museum, a nongovernmental organization that retrieves dead animals and preserves them for educational purposes.

"It was so bad the plastic was beginning calcification," Blatchley said of the process in which calcium builds up in the body and causes tissue to harden.

After a necropsy, Blatchley said, the animal appeared to have died from emaciation and dehydration - with the plastic hindering its ability to eat or drink. The whale had also been vomiting blood before it died, he added.

Images of the whale have gone viral worldwide, as more and more people are calling for bans on single-use plastic, often focusing on its effects on the ocean.

An estimated 8.8 million tons of plastic spill into the ocean annually. In the Philippines, Blatchley said, it's particularly bad. Over the past 10 years, his group has recovered 57 dead whales and dolphins, many of which died from plastic ingestion.

"The Philippines needs to change," Blatchley said, adding that he hopes the latest attention on the whale will shine a light on the effects of pollution before "nothing will be left."

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Whale in the Philippines dies with 88 pounds of plastic in stomach

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A museum in the southern Philippines said it made a stomach-churning discovery when a dead beaked whale was found with 88 pounds of plastic in its stomach.

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RESEARCHED BY: VILLABLANCA, ANGEL MYRCKY

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5.) LOCAL OR NATIONAL NEWS VIDEO SEGMENT

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5.) LOCAL OR NATIONAL NEWS VIDEO SEGMENT

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URL: https://www.youtube.com/watch?v=bxnMsZDBz3E

TITLE: One Mindanao: Fish Kill

AUTHOR: GMA Regional TV

DATE PUBLISHED: January 30, 2023

KEY POINTS: Almost 17.7 Million PHP & 250,000 kg total amount of fishes were killed in Lake Sebu in South Cotabato. 3 barangays that are affected were sent out in state of calamity. The Government of South Cotabato plans to lessen the usage of fish nets from 18.6% to 10% because only 3,575 net cages are allowed yet this time there are more than 6,000 in use.

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URL: The Philippines' plastic problem: waterways polluted by single-use packaging • FRANCE 24 English - YouTube

TITLE: The Philippines' plastic problem: waterways polluted by single-use packaging

AUTHOR: FRANCE 24 English

DATE PUBLISHED: Nov 17, 2023

KEY CONCEPT: The issue of plastic pollution particularly in its waterways, caused by the widespread use and improper disposal of single-use packaging. This highlights the environmental impact of plastic waste, especially in coastal areas and water bodies, and underscores the need for effective waste management and sustainability measures to address this problem.

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The Philippines' plastic problem: waterways polluted by single-use packaging • FRANCE 24 English

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URL: https://oar.marine.ie/handle/10793/1729

TITLE: Explorers SDG No.14_life below water

AUTHOR: Dromgool-Regan, Cushla

DATE PUBLISHED: 2019

KEY POINTS: The poster displays a stunning photo of creatures in an aquarium with a young girl staring up at various species, reminding us of our impact on the ocean and how the ocean affects our life.

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RESEARCHED BY: CATAM-ISAN, VINCRYS ABRUCE

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8.) PUBLIC SERVICE MESSAGE OR PROMOTIONAL VIDEO

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8.) PUBLIC SERVICE MESSAGE OR PROMOTIONAL VIDEO

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URL: https://web.facebook.com/permalink.php?story_fbid=pfbid02drLPsL5c3Gn1wXGgMaUomTznQGdex7Mr5PpuPEa2iFWxawsi562DnUKiUsCrYQPdl&id=100076631003230

TITTLE: LOOK | COSTAL CLEAN-UP DRIVE IN CALUMPANG, GENERAL SANTOS CITY

AUTHOR: Bahaghari Sox

DATE PUBLISHED: Spetember 26, 2023

KEY POINTS: The International Coastal Cleanup (ICC) is an annual volunteer initiative that aims to preserve and safeguard the oceans, waves, and beaches. On October 1, 2023, as part of ICC Day, the BAHAGHARI SOX will hold a coastal cleanup drive at Sarangani Bay, General Santos City. The goals are to remove garbage, identify litter sources, promote behavioral change, and raise awareness about marine conservation. Ocean rubbish is a severe hazard to human health, animals, and local economies, making cleanup efforts critical. In 2003, Proclamation No. 470 proclaimed the third Saturday of September as ICC Day in the Philippines, underlining the country's commitment to combating marine litter.

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RESEARCHED BY: VILLABLANCA, ANGEL MYRCKY

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URL: https://earthjournalism.net/stories/water-crisis-looms-in-davao

TITLE: Water crisis looms in Davao

AUTHOR: Henrylito Tacio

DATE PUBLISHED: 23 June 2014

KEY POINTS: "We have a water crisis in the city, not only in the second but also in the first district," said Second District City Councilor Danilo C. Dayanghirang, chairman of the Council Committee on Environment and Natural Resources. Various factors contribute to water scarcity. These include climate fluctuation, demographic patterns, and unsustainable water use. In some urban areas of the country where water is available, 50 percent never reaches the targeted users due to leakage, theft, and bad management. These identified issues are exacerbated by the degradation of the water resource base.

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Davao City is experiencing water crisis.

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14.) NON-GOVERNMENT ORGANIZATION OR ACADEMIC INSTITUTION ARTICLE

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14.) NON-GOVERNMENT ORGANIZATION OR ACADEMIC INSTITUTION ARTICLE

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URL: https://rkcmpd-eria.org/how-plastics-ingestion-is-killing-the-marine-life-in-the-philippines/

TITLE: How Plastics Ingestion is Killing the Marine Life in the Philippines

AUTHOR: ERIA

PUBLISHED: 9 August 2021

KEYPOINTS: The story of research on plastic debris impact on marine life in Davao, the Philippines, and its vicinity began with a fateful meeting between a marine biologist taking his students on a museum tour and a science museum director who happened to be their guide.

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URL: https://www.youtube.com/watch?v=fxjpjw1OucM

AUTHOR: BECOMINGFILIPINO

TITLE: DAVAO PROVINCE FLOODED - Beach Land Extreme Rain... Fishpond House River Overflowing!

DATE PUBLISHED: April 7, 2022

KEY CONCEPT: Shows the vulnerability of Davao Province's coastal areas to floods after heavy rains and river overflows. The combination of extreme weather events, such as torrential rain and rising river levels, causes inundation of low-lying beach land and fishpond areas, posing dangers to houses and infrastructure. This emphasizes the necessity of proactive flood management methods, such as enhanced drainage and early warning systems, in mitigating the effects of flooding and protecting residents in Davao Province.

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DAVAO PROVINCE FLOODED - Beach Land Extreme Rain... Fishpond House River Overflowing!

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URL: https://www.rappler.com/nation/philippines-dominates-global-ocean-plastic-pollution-chart-at-36-shows-study/

TITLE: Philippines dominates global ocean plastice pollution chart at 36%, shows study

AUTHOR: Cong Corrales

DATE PUBLISHED: Oct 10, 2023

KEY POINTS: An international study commissioned by Utility Bidder revealed that the Philippines is the top contributor to plastic pollution in the oceans, emitting an average of 3.30 kilograms of plastic waste per person annually. The study monitored countries based on their waste emissions into the oceans, mismanaged waste, and quantities of plastic waste exported, highlighting the Philippines as the leading nation in plastic waste emissions per capita. These findings underscore the urgent need for concerted efforts to address plastic pollution and implement effective waste management strategies in the Philippines and globally.

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CAGAYAN DE ORO, Philippines ― An international study on plastic pollution has shown that the Philippines is the world's leading contributor to plastic pollution in the oceans, with an average of 3.30 kilograms per person per year.

Utility Bidder, an independent United Kingdom-based organization dedicated to identifying gaps in the market and providing efficient, transparent services to help businesses find the best utility tariffs, commissioned the Plastic Polluters study, and released it in September. The group was originally known as Business Energy Consultant established in 2009.

As part of the study, the group monitored countries that emit the most waste per capita into the oceans, countries with the highest likelihood of plastic waste emissions, nations with the most mismanaged waste, and those exporting the largest quantities of plastic waste.

The study's findings indicated that the Philippines ranked first as the country with the highest plastic waste emissions into the ocean per person each year, at 3.30 kg.

Suriname in South America ranked second, with 2.89 kg per capita per year.

Trinidad and Tobago in the Caribbean took the third spot, with 2.55 kg per capita per year.

Fourth and fifth were Saint Lucia in the Caribbean Sea (2.45 kg per capita per year) and Malaysia in Southeast Asia (2.29 kg per capita per year), respectively.

"The study revealed that more than 350,000 tons of plastic waste enter the ocean from the Philippines annually," read part of the study.

This 350,000-ton figure from the Philippines accounts for 36% of the world's total plastic waste, according to the study.

Saddened

The data left the head of the Cagayan de Oro City Local Environment and Natural Resources Office (Clenro), Armen Cuenca, disheartened.

"That is so sad to know," Clenro chief Armen Cuenca told Rappler on Tuesday, October 10.

In Cagayan de Oro alone, Cuenca pointed out that their data indicate an alarming increase in waste being dumped into the city's sanitary landfill, which has now reached an average rate of 45,000 cubic meters per month.

The study by Utility Bidder showed the alarming yearly increase in plastic waste entering the world's oceans, posing a severe threat to marine life.

While the Philippines holds the top rank as a plastic polluter in the study, Utility Bidder cites the country's efforts to mitigate the likelihood of plastic waste emissions.

Policy approach

In September 2021, the Philippines began implementing an Extended Producer Responsibility (EPR) program to address environmental concerns related to product packaging and waste.

EPR is a policy approach that holds producers accountable for their products' entire life cycle, including disposal and recycling.

In the Philippines, EPR initiatives primarily targeted addressing the growing issue of plastic pollution and enhancing recycling rates.

The key components of the Philippine EPR program included:

Mandatory reporting - producers and manufacturers were required to report data on the types and quantities of packaging materials they used.

Financial responsibility - producers were expected to financially contribute to the recycling and disposal of their product packaging materials. This financial obligation aimed to encourage producers to adopt more environmentally friendly packaging and invest in recycling infrastructure.

Recycling targets - the government established recycling targets for various types of packaging materials, and producers were obligated to meet these targets.

Waste reduction measures - producers were encouraged to implement measures to reduce the amount of packaging material used in their products, such as using lighter materials and more recyclable options.

Cagayan de Oro's solid waste problem

In Cagayan de Oro, the possibility of waste emissions into the ocean is of great concern, given that the city's solid waste has increased by 52% over the past five years.

Based on Clenro's data, the city's garbage volume rose from 300,890 to 573,863.30 cubic meters annually, from 2017 to 2022.

To combat the garbage problem, the city council approved the Integrated Solid Waste Management Ordinance (13378-2018) in 2018.

Under this ordinance, Clenro has been tasked to ensure that residents properly dispose of their trash to avoid penalties and sanctions.

Violations under the ordinance include the following:

The use of plastic cellophane, except for items exempted by the ordinance.

Littering, which entails disposing of garbage in public places, including cigarette butts.

Illegal/bulk dumping, which involves discarding trash in non-designated areas, whether public or private.

Open burning of garbage, including dried leaves.

Failure to segregate trash.

The ordinance also reminded the city's 80 barangays to establish materials recovery facilities (MRF) accessible to their constituents.

Clenro's penalty matrix is as follows:

Issuing plastic bags carries a penalty of P3,000 per plastic bag issued by the establishment.

Illegal or bulk dumping results in a fine of P5,000 or three months imprisonment or both.

Littering, open burning, and unsegregated garbage violations incur fines ranging from P500 to P2,000 or one to five days of community service.

Since 2020, Clenro has taken action against 1,308 violators for using single-use plastic, 127 individuals for littering, 84 people for illegal dumping, 74 individuals for open-pit burning, and 118 violators for dumping unsegregated garbage.

The city has also begun implementing its 10-year solid waste management plan, which aims to reduce the city's garbage volume. One of the goals is to reduce the monthly garbage volume from 33,000 cubic meters this year to 30,000 cubic meters monthly by 2024 through waste diversion and the construction of recycling facilities.

"We have partnered with UN Habitat for the Healthy Ocean Clean Cities Initiative and World Wide Fund for the Clean Ports Project," Cuenca said.

This partnership involves activities like organizing waste pickers at the city's old dumpsite into a cooperative to produce "eco-bricks with laminated plastic as one of the components" and having a plastic densifier for recycling plastics into other products.

Cuenca also said that in the first quarter of 2024, Clenro will be implementing the Trash Trap along Bitan-ag Creek.

"We are also exploring the ultimate solution for our solid waste, which is waste-to-energy," he said. - Rappler.com

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Philippines dominates global ocean plastic pollution chart at 36%, shows study

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While the Philippines holds the top rank as a plastic polluter in the study, the group Utility Bidder cites the country's efforts to mitigate the likelihood of plastic waste emissions

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RESEARCHED BY: CATAM-ISAN, VINCRYS AMBRUCE

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URL: https://philjournalsci.dost.gov.ph/home-1/49-vol-145-no-1-march-2016/568-ingestion-of-marine-plastic-debris-by-green-turtle-chelonia-mydas-in-davao-gulf-mindanao-philippines

TITLE: Ingestion of Marine Plastic Debris by Green Turtle (Chelonia mydas) in Davao Gulf, Mindanao, Philippines

AUTHOR: Neil Angelo S. Abreo

DATE PUBLISHED: N.D

Key Content: Marine plastic debris is a global threat to marine biodiversity.

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URL: https://www.youtube.com/watch?v=kjHAh9CdZPU

TITLE: Episode 4: Overview of the Philippine Clean Water Act

AUTHOR: EMB Central Luzon

DATE PUBLISHED: Aug 23, 2021

KEYPOINTS: What is the Clean water Act? This Act defines water quality standards and regulations, as well as strategies for reducing and controlling pollution from land-based sources. The Act governs water quality management in all bodies of water, whether aquifers, rivers, lakes, or marine.

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Episode 4: Overview of the Philippine Clean Water Act

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URL:https://www.youtube.com/watch?v=gxqgm-ruiW8

TITLE: The truth is, due to overfishing, illegal fishing, climate change, and water pollution

Philippine Seas: A documentary by Atom Araullo

AUTHOR: GMA PUBLIC AFFAIRS

DATE PUBSLISHED: NOVEMBER 17, 2017

KEYPOINTS: Through this video, we learn a lot about the varied life waters in the Philippines, as well as the many marine life species.

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Philippine Seas: A documentary by Atom Araullo (Full Episode) (with English subtitles)

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URL: https://www.youtube.com/watch?v=jGXOa-5VFq4

TITLE: Introduction to Water Pollution in Philippines

AUTHOR: Jesselito Baring

DATE PUBLISHED: 4 Jan 2021

KEY POINTS: The video lectures us about water pollution and the effects of water pollution on our health.

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Introduction to Water Pollution in Philippines

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URL: https://news.mongabay.com/2019/12/philippine-coastal-town-leads-war-against-plastic-trash-in-mindanao/amp/

TITLE: Philippine coastal town leads war against plastic trash in Mindanao

AUTHOR: Bong S. Sarmiento

DATE PULISHED: February 2020

KEY POINTS: The town of San Isidro in Mindanao committed to eliminating plastic pollution in ten years after locals experienced repeated cases of rescuing sea turtles that eventually die with stomachs full of plastic wastes.

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Philippine coastal town leads war against plastic trash in Mindanao

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DAVAO, Philippines - On August 4, 2018, a fisherman found an endangered green turtle (Chelonia mydas) floating weakly in the Davao Gulf, a diverse marine ecosystem and rich fishing ground spanning 308,000 hectares in the southern Mindanao region. The fisherman brought the stranded juvenile female green turtle ashore where it breathed more easily after a plastic food [...]

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RESEARCHED BY: CATAM-ISAN, VINCRYS AMBRUCE 

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URL: https://www.goodreads.com/book/show/36349758-the-big-book-of-the-blue

TITTLE: The Big Book of the Blue

AUTHOR: Yuval Zommer

DATE PUBLISHED: June 5, 2018

KEY POINTS: The "Big Book of the Blue" is a comprehensive guide for young oceanographers, providing essential knowledge about underwater animals and their habitats. Through charming illustrations, readers learn about the diversity of marine life, from sea turtles and whales to sharks and seahorses, while exploring different underwater ecosystems like coral reefs and deep sea beds. Additionally, the book addresses important themes such as conservation efforts, animal endangerment, and how individuals can contribute to saving sea life, making it an engaging and educational resource for curious young minds.

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The Big Book of the Blue (The Big Book Series)

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Read 78 reviews from the world’s largest community for readers. Following The Big Book of Bugs and The Big Book of Beasts , the hugely successful series ta…

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URL: https://www.mdpi.com/2077-1312/10/10/1532

TITLE: Unraveling Macroplastic Pollution in Rural and Urban Beaches in Sarangani Bay Protected Seascape, Mindanao, Philippines

AUTHOR: Frank T. Acot, Jr. ,Recca E. Sajorne ,Nur-Ayn K. Omar,Peter D. Suson,Lynn Esther E. Rallos and Hernando P. Bacosa

DATEPUBLISHED: OCTOBER 19. 2022

KEYPOINTS: Plastic pollution in the ocean is an emerging environmental concern in the Philippines. This study was conducted to investigate the prevalence of macroplastics, composition of plastic litter, and the clean-coast index (CCI) of urban and rural beaches in Sarangani Bay.

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1. Introduction

Plastic pollution in the ocean is a rapidly emerging global environmental concern, with high concentrations (up to 580,000 pieces per km ²) and a global distribution, driven by exponentially increasing production [ 1]. The exponential increase in the use of plastics in modern society and the inadequate management of the resulting waste have led to plastic accumulation in the marine environment [ 2]. This is a major environmental issue that affects coasts and coastlines all around the world [ 3].

According to a model developed by Meijer et al. [ 8], the Philippines is the largest emitter of plastics from rivers to the marine environment. The country also ranks third in total plastic waste input from land into the ocean, just below China and Indonesia, by contributing 0.28-0.75 million metric tons of plastic litter every year [ 9]. These findings are mainly based on simulation and numerical modeling, empirical observations, and a limited amount of field data. Validating the results of these findings through a more representative field sampling is crucial to science-based decision-making. Several studies on plastic pollution monitoring were conducted on the beaches of the Philippines, and the majority of the beaches were categorized as dirty to extremely dirty based on the clean-coast index (CCI) [ 10, 11, 12]. These beach areas were mostly categorized as urban areas where the rate of infrastructure development is higher than in rural areas. Aside from this, activities such as fishing and swimming are also frequently conducted by the local community and beachgoers, which helps development and economic growth, particularly in local coastal communities [ 13]. However, these activities may contribute to plastic pollution as indiscriminate disposal of solid waste is highly rampant in coastal settlements [ 12, 14, 15, 16]. This emerging threat requires the development and enforcement of plastic regulation policies. In a study conducted by Galarpe et al. [ 17], it was determined whether studies on macro- and microplastics should be the basis of the institutionalization of existing policies on waste management. Unfortunately, they were unable to arrive at sound conclusions due to a limited number of studies on macro- and mesoplastics in the Philippines, and therefore a limited amount of field data, considering that the country is seen as a plastic pollution hotspot around the world.

The intensity of human pressure on marine systems has led to a push for stronger marine conservation efforts. The Philippines has been the site of some of the earliest marine reserves and marine-protected areas [ 18]. Marine reserves, as defined by [ 19], are areas of marine environment protected from various forms of human exploitation. Within the last decade, South Cotabato-Sarangani-General Santos City (SOCSARGEN) in the southern Philippines has emerged as one of the most economically dynamic regions in the Philippines [ 20]. A significant factor propelling growth in the area is the presence of Sarangani Bay Protected Seascape (SBPS), a marine-protected area that provides various goods and services that cater to the SOCSARGEN economy. The bay encloses an area of 449.22 km ² and is bounded by the Sarangani Province and chartered city of General Santos. Besides providing a sanctuary for marine life, the bay also offers a wide range of choices for recreational activities due to the presence of white-sanded beaches, beautiful coral reefs, and scuba diving sites [ 21]. Despite its status as a marine-protected area, the bay has faced several environmental pressures, including massive population growth, uncontrolled human settlement in coastal areas, urbanization, and various anthropogenic pressures, including pollution [ 22]. However, the plastic pollution in the area has not been documented. Thus, with the growing concern of plastic pollution in the Philippines, this study was conducted to (1) determine the density of macroplastic litter on the rural and urban beaches, (2) identify the types of macroplastic litter, (3) quantify the accumulation rate of macroplastic litter for eight non-consecutive days, and (4) determine the clean-coast index of rural and urban beaches of Sarangani Bay Protected Seascape. To the best of our knowledge, this is the first monitoring of marine plastic litter pollution in the protected seascape of the Philippines.

2. Materials and Methods

The study was conducted in Sarangani Bay Protected Seascape ( Figure 1). Sarangani Bay is located on the southern tip of Mindanao Island in the Philippines. It opens up to the Celebes Sea in the Pacific Ocean. The bay was declared a protected seascape in 1996 (Proclamation no. 756 signed by President Fidel V. Ramos), covering an area of 215,950 hectares. Plastic litter was sampled from 14 beaches in rural (n = 7) and urban (n = 7) areas in Sarangani Bay, and the sampling sites were classified as urban (U) or rural (R) ( Table 1).

Sampling was performed by following the methods of Sajorne et al. [ 12] with minor modifications. At each sampling site, a 100-m transecting line was established parallel to the shoreline. Three quadrats measuring 4 m × 4 m were laid along the transecting line. Plastic litter found within the quadrat was collected, counted, and classified. The collected plastics were classified based on their uses, such as food packaging, polyethylene bags (locally known as sando bags), Styrofoam, mats, plastic bottle, plastic fragments, plastic caps, toiletries, Styrofoam cups, clothing, and other items ( Figure S1) [ 12, 23]. Meanwhile, to monitor the accumulation rate of macroplastics, non-consecutive sampling was conducted for eight days in beach areas [ 16]. The transecting line and quadrats were placed in the same area in each sampling site throughout the monitoring. Sampling collection was conducted from 11 August 2021 until 4 September 2021. The collection of macroplastics was conducted on Wednesdays to represent the weekdays and Saturdays to represent the weekends

The density of plastic litter was determined by dividing the total number of items per unit area sampled [ 24, 25] and reported as items/m ² ± SD. The cleanliness of the coastal beaches was assessed using the clean-coast index (CCI) [ 26], where CCI is equal to the density of litter items/m ² multiplied by 20, a constant to make the numerical value of CCI more intuitive. According to the CCI scale, values from 0 to 2 are very clean, 2 to 5 are clean, 5 to 10 are moderately clean, 10 to 20 are dirty, and greater than 20 are extremely dirty. Meanwhile, the daily accumulation rate, mean count, and cumulative density were computed using the formula of Ammendolia et al. [ 27]. The accumulation rate was reported as items d −1 m −2 [ 28].

An independent two-sample t-test was conducted to determine significant differences between urban and rural beaches in Sarangani Bay in terms of macroplastic abundance as the data are parametric. Statistical analysis was performed in Statistical Package for the Social Sciences (SPSS) version 26, a free software, developed by International Business Machines Corporation (IBM) headquartered in Armonk, New York, and values of p < 0.05 were considered significantly different.

3. Results

Regarding the sampling sites, all beaches were found to contain macroplastic litter. A total of 2580 items of plastic litter were collected over a cumulative area of 672 m ² in urban and rural areas of Sarangani Bay Protected Seascape, with a density of 3.83 items m −2. The highest density was recorded in urban areas U3 (1.06 items m −2), U4 (0.88 items m −2), and U5 (0.82 items m −2) ( Table 1). Overall, the plastic litter density on urban beaches (0.66 items m −2) was significantly higher (p < 0.05) than the plastic density on rural beaches (0.29 items m −2) ( Figure 2).

In terms of macroplastic types, there is a difference in the percentage composition in rural and urban areas of Sarangani Bay Protected Seascape ( Figure 3). In urban areas, food packaging (27%, n = 474 items), polyethylene bags or sando bags (15%, n = 271 items), and mats (13%, n = 237 items) were the most predominant types of macroplastic. Meanwhile, sando bags (23%, n = 180 items), food packaging (19%, n = 154 items), and Styrofoam (14%, n = 108 items) were predominant in the rural areas. Overall, the types of plastics sampled were predominantly food packaging (24%, n = 628), sando bags (18%, n = 451), and other items (19%, n = 496). The "other items" were composed of combined plastic classifications that made up less than two (2%) percent of the total plastic types.

Meanwhile, Sarangani Bay Protected Seascape was monitored for eight non-consecutive days, and it revealed that the daily density of macroplastic ranged from 0 to 2.52 items m −2, with a mean density of 0.48 items m −2 (SD = 2.26) ( Table 2). The accumulation rates of macroplastic litter ranged from 0.07 items d −1 m −2 to 0.40 items m −2, with an average rate of 0.18 items d −1 m −2. On average, the accumulation rate in urban areas (0.25 items d −1 m −2) was significantly higher than those in rural areas (0.11 items d −1 m −2) (p = 0.007). Meanwhile, it was shown that day 2 of the collection was found to have the highest density (1.35 items d −1) (n = 456), while the lowest density (0.75 items d −1) (n = 255) was recorded on day 8 ( Figure 4). Over the sampling period, a significant decrease in the density of plastic litter on both urban and rural beaches was not observed, which was characterized by a recurring amount or lingering presence of these pollutants in the area ( Figure 4).

Based on the CCI of the beaches in Sarangani Bay Protected Seascape, 36% (5 out of 14) were considered dirty to extremely dirty ( Table 3). Out of the seven urban beaches, only one (site U3) (21.35) was categorized as extremely dirty, with a high CCI. Four of the sampling sites (U1, U2, U4, and U5) (11.25 to 17.65) were categorized as dirty. However, there were still some beaches (U6 and U7) categorized as clean ( Table 3). Meanwhile, on rural beaches, all of the sampling sites were considered as clean to moderately clean. Notably, dirty to extremely dirty sites were located in urban areas, while clean to moderately beaches were located in rural areas. Overall, on average, Sarangani Bay (9.59) is categorized as moderately clean.

4. Discussion

With these results, we confirmed the significant difference between the amount of macroplastic litter in rural and urban beaches in Sarangani Bay Protected Seascape. Urban beaches were noted to have two times higher macroplastic litter density compared to rural beaches. We observed that within the urban beaches, fishing activity was frequently conducted by the local community, while recreational activities were very seldom. However, no fishing paraphernalia was collected throughout the study period. Additionally, there are several residential areas within the vicinity of the urban beaches which can be one of the main sources of plastic litter. It is believed that the number of people in an area has a significant relationship to the quantity of plastic waste disposal [ 12, 13]. These factors might be the reason why we recorded the highest density and accumulation rate of macroplastic litter at urban beach sites U3 and U4. This result also supports the findings of Sajorne et al. [ 12, 24], where the majority of the plastic litter was collected from residential and fishing areas. Meanwhile, several studies on plastic monitoring on the Philippine coasts also found plastic food wrappers/containers, cups, and sachet wrappers [ 10, 11, 29] as the dominant macroplastic waste. Basic necessities and commonly used plastic types are believed to be the underlying reasons for such findings. For instance, sando bags were listed as the dominant type of macroplastics collected in rural areas, while they were placed second in urban areas. This may be due to the need for sando bags for carrying food and other purchased items in rural areas, which may not be the same in urban areas where food and other items are in closer proximity to buyers. Living conditions and activities in urban areas seem to allow for easy purchases anytime and anywhere. In rural areas, however, stores are located far apart, which probably drives residents to purchase items in bulk, resulting in the use of more sando bags. During sampling, it was also observed that mats and clothing were littering the beaches of urban areas but were hardly seen in rural areas. In urban areas, residents can conveniently replace such items because of greater access to them, whereas rural residents are known to recycle both mats and clothing. Conversely, on rural beaches, activities related to tourism, such as swimming, were more frequently conducted by beachgoers than fishing activities. The high number of plastic cups in rural areas may be attributed to tourism as beachgoers or tourists usually bring disposables for special occasions or recreational activities [ 30]. This shows that the overall plastic usage in urban and rural areas varies. It can be said that the plastic composition is due to the necessities and activities of a particular place. The findings of this study, however, do not deviate from the findings of other studies that found plastic food wrappers and containers/sando bags to be the dominant plastic waste on or near the beaches of the Philippines [ 31].

The temporal pattern observed in this study reveals that plastic spells a big problem for the future as it is non-biodegradable. In a study conducted by Browne et al. [ 32], the influence of physical factors, such as wind, wave action, and the density of plastic litter, on the spatial pattern of the accumulation of plastic litter was highlighted. During the collection, it was observed that the difference in waste generation was due to geographical location, and the number of residents [ 33]. Rural areas were a bit more mountainous with rocky beaches, and the number of households was not yet populous, unlike urban areas where beaches were plainly sandy and the coastline was occupied with houses. Additionally, the rural areas were close to the open sea, while the urban areas were by the bay. These data suggest that the accumulation rate of plastic in a given area does not depend only on human population size, but also on the geographical formation and activity of the site. Other than that, we also consider the influence of winds and waves [ 34, 35] and meteorological conditions [ 36] on the transport and accumulation of macroplastic litter in these areas. In comparison to other areas in the Philippines, the beaches of Sarangani Bay Protected Seascape are cleaner than the beaches of Puerto Princesa, Palawan (29) [ 12], and Macajalar Bay, Misamis Oriental (84.99) [ 11]. In this study, the urban sites of Sarangani Bay were found to be moderately clean, dirty, and extremely dirty. Our CCI findings agree with the findings of Esquinas et al. [ 11] and Kalnasa et al. [ 29], who found the urban sites of Baloy, Macabalan, Bonbon, and Balua as clean and extremely dirty. As aptly stated, the highly urbanized nature of the adjacent environment greatly influenced the litter deposition in the surface sand of Macajalar Bay [ 11].

This study also reveals that plastic litter is now recognized as an emerging threat to Sarangani Bay. Marine macroplastic litter not only negatively affects ecology and biodiversity [ 37] but also has a direct impact on the economic value [ 7] of the coastal community as Sarangani Bay is a protected seascape and uplifts the economy of the SOCCSARGEN region through tourism. However, this study also revealed that tourism-related items were the dominant macroplastic litter found on the rural and urban beaches of Sarangani Bay. With the presence of plastic litter on coastal beaches, the beaches lose their aesthetic value [ 38], thus making them unattractive and unsuitable for recreational activities [ 39, 40]. The advancement toward meeting the main tenets of the UN's Sustainable Development Goals (SDG) has been hampered by insufficient initiatives for solid waste management policies at regional and national levels.

Meanwhile, SDG 6-clean water and sanitation-and SDG 14-life below the water-are both directly impacted by the pollution brought on by incorrect solid waste disposal in coastal regions. Recent reports in Philippine marine waters have also revealed the first case of plastic ingestion in a rare Deraniyagala's beaked whale (Mesoplodon hotaula) [ 41] and green sea turtle (Chelonia mydas) [ 42]. As a result, there may be a loss of biodiversity in both aquatic and terrestrial ecosystems as well as a reduction in the livelihoods of the local coastal community [ 43]. Furthermore, if this continues, through the influence of physical and chemical factors [ 44], secondary MP and nanoplastics will eventually form and put the health of the local coastal community at risk [ 7]. Due to its high dependence on marine foods, SDG 3-good health and welfare of the local community-and SDG 12-responsible consumption and production-become vulnerable as a result of these records of plastic ingestion in biota. Pieces of evidence on microplastic ingestion in fish and other marine animals [ 45] have also been reported in the Philippines. Overall, the occurrence of marine macroplastic pollution in the urban and rural beaches of Sarangani Bay can be partially ascribed to inadequate regional and national initiatives for solid waste management in Mindanao.

5. Conclusions

This study is the first to provide an account of the current status of plastic litter on urban and rural beaches in Mindanao, Philippines. We observed that plastic litter is more prevalent in urban areas than in rural areas in terms of density. The collection patterns of plastic litter suggest that the number of plastics in a given area may either increase or decrease but is never zero, which means that plastic waste is always being deposited in coastal areas, possibly aided by wind and wave actions. Similar to other studies, the dominant types of plastic litter are food packaging and sando bags. The values of the clean-coast index in this study revealed that beaches in urban areas are moderately clean, dirty, and extremely dirty, while rural areas are clean and moderately clean. Since the urban and rural beaches of Sarangani Bay were classified over a range of moderately clean to extremely dirty, this implies that both beach areas require a stricter plastic waste policy implementation-one for maintaining the clean status and the other for rehabilitating dirty beaches. Furthermore, data on the identification of dominant macroplastic items can serve as a guide for legislators in creating policies to strengthen the promotion of environmentally friendly products to curb or limit the rapid production of these dominant items.

Supplementary Materials

The following are available online at https://www.mdpi.com/article/10.3390/jmse10101532/s1, Figure S1: Types of macroplastic litter based on their uses: (A) food packaging; (B) fragment; (C) polyethylene bag or sando bag; (D) Styrofoam; (E) plastic bottle; (F) bottle cap; (G) mat; (H) toiletry; (I) disposable cup.

Author Contributions

Conceptualization, F.T.A.J. and H.P.B.; investigation, F.T.A.J.; formal analysis, F.T.A.J., R.E.S., N.-A.K.O., P.D.S., L.E.E.R. and H.P.B.; writing original draft preparation, F.T.A.J., R.E.S. and N.-A.K.O.; writing-review and editing, P.D.S., L.E.E.R. and H.P.B.; supervision, P.D.S., L.E.E.R. and H.P.B. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Institutional Review Board Statement

Informed Consent Statement

Acknowledgments

This study was supported by the Philippines' Department of Science and Technology through the Accelerated Science and Technology Human Resource Development Program (DOST-ASTHRDP). The first author would like to thank the DOST-ASTHRDP for the scholarship to pursue graduate studies at MSU-IIT and the Department of Environment and Natural Resources (DENR) Region 12, especially the Protected Area Management Board of Sarangani Bay Protected Seascape for allowing the researchers to conduct this study in Sarangani Bay.

Conflicts of Interest

The authors declare no conflict of interest.

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Figure 2. Density of macroplastics sampled from seven rural beaches and seven urban beaches of Sarangani Bay, Philippines. Error bars represent the standard deviation of 14 sampling times. Different letters indicate significant differences (p < 0.05).

Table 2. Summary of macroplastic surveys including the item counts, densities (items m −2), and accumulation rates (items d −1 m −2) in sampling sites of Sarangani Bay Protected Seascape. The standard deviation (SD), daily minimum (min.), and maximum (max.) counts and densities are also presented.

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Acot, F.T., Jr.; Sajorne, R.E.; Omar, N.-A.K.; Suson, P.D.; Rallos, L.E.E.; Bacosa, H.P. Unraveling Macroplastic Pollution in Rural and Urban Beaches in Sarangani Bay Protected Seascape, Mindanao, Philippines. J. Mar. Sci. Eng. 2022, 10, 1532. https://doi.org/10.3390/jmse10101532

Acot FT Jr., Sajorne RE, Omar N-AK, Suson PD, Rallos LEE, Bacosa HP. Unraveling Macroplastic Pollution in Rural and Urban Beaches in Sarangani Bay Protected Seascape, Mindanao, Philippines. Journal of Marine Science and Engineering. 2022; 10(10):1532. https://doi.org/10.3390/jmse10101532

Chicago/Turabian Style

Acot, Frank T., Jr., Recca E. Sajorne, Nur-Ayn K. Omar, Peter D. Suson, Lynn Esther E. Rallos, and Hernando P. Bacosa. 2022. "Unraveling Macroplastic Pollution in Rural and Urban Beaches in Sarangani Bay Protected Seascape, Mindanao, Philippines" Journal of Marine Science and Engineering 10, no. 10: 1532. https://doi.org/10.3390/jmse10101532

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# data[].attributes.attachment_link.title
Unraveling Macroplastic Pollution in Rural and Urban Beaches in Sarangani Bay Protected Seascape, Mindanao, Philippines

# data[].attributes.attachment_link.description
Plastic pollution in the ocean is an emerging environmental concern in the Philippines. This study was conducted to investigate the prevalence of macroplastics, composition of plastic litter, and the clean-coast index (CCI) of urban and rural beaches in Sarangani Bay. Plastic litter was collected by delineating a 100-m transecting line with three 4 m × 4 m quadrats.