Persistent Organic Pollutants in the Salish Sea
Here’s what researchers who study the Salish Sea want you to know about persistent organic pollutants.
By Anna Finch, Marine Science Team intern
The Marine Science Team at foundry10 supports local youth taking action for global ocean and climate resilience while anchoring all programs and partnerships in environmental justice. Within these guiding frameworks, foundry10 runs an undergraduate internship program to draw upon the unique perspectives of young adults and collaborate on current marine science education projects and programming.
This story was written by foundry10 Marine Science Team intern Anna Finch, a student at the University of Washington pursuing a degree in Oceanography and Biochemistry with Interdisciplinary Honors.
Organic pollutants are organic chemicals in the environment that are either not naturally found in large amounts or not naturally found at all. They are known to usually cause deleterious effects, especially on wildlife, and many of them can bioaccumulate. Some of the more commonly known organic pollutants are persistent organic pollutants (POPs). These were defined in the Stockholm Convention, an international treaty on persistent organic pollutants, as organic chemical substances that persist in the environment for long periods of time, are widely distributed through natural processes, bioaccumulate in the fatty tissues of living organisms, and exhibit toxicity to humans and wildlife (UN Environment Programme, n.d.). These include DDT, lindane, and polychlorinated biphenyls, among others. Lesser known organic pollutants often fit into the category of emerging organic pollutant (EOP), or organic contaminants that are not yet regulated. These often include chemicals from pharmaceuticals and personal care products.
With so many different organic pollutants, many of which are rarely talked about to the public, we believe that it is immensely important to educate youth about these issues. We asked researchers and professionals from the Salish Sea region in fields related to organic pollution what specific pollutants they think there should be greater awareness of and that they think should be taught about in schools. Our hope is that this information can be used by educators to teach students about organic pollution in the marine environment.
It’s important to note that this is by no means a comprehensive list of all organic pollutants in the oceans right now, nor is it meant to imply that these pollutants are more harmful or severe than other organic pollutants that are not mentioned. In addition, this is not a ranking of the pollutants presented. There are thousands of different organic pollutants impacting the oceans and it’s immensely difficult to even identify many of them. Some researchers take a more human activity-based approach to researching organic contaminants as a complex mixture rather than focusing on specific pollutants. However, for the sake of teaching and learning, it can be beneficial to highlight a few specific pollutant case studies to raise awareness of organic pollution.
Below are some of the pollutants that the survey participants chose to talk about.
Endocrine disrupting compounds (e.g. ethinyl estradiol, nonylphenol, octylphenol ethoxylates)
What is the endocrine system?
The endocrine system produces and distributes hormones to regulate metabolism, growth and development, blood sugar levels, sexual function, reproduction, sleep, mood, and many other biological processes in the body (“What is the Endocrine System?”, n.d.).
Where do these pollutants originate from?
Personal care products, steroidal pharmaceuticals.
What are the main pathways these pollutants take to enter into the Salish Sea?
Storm drains/urban runoff, sewer systems.
Why are these pollutants important to know about?
“They have effects on aquatic organisms at very low concentrations and are continuously released from wastewater treatment plants.”
“Higher concentration and detection frequency.”
More information about these pollutants
Endocrine disruptors interfere with the endocrine system by causing overproduction or underproduction of hormones, leading to increased cancer risk as well as issues in development, reproduction, and immune and nervous system function. This can occur if the chemical mimics a natural hormone, blocks the effects of a hormone, or directly stimulates or inhibits the endocrine system (“What is Endocrine Disruption?”, n.d.) .
Per- and polyfluoroalkyl substances (PFAS)
Where does this pollutant originate from?
Household or lawn care products, personal care products, manufacturing/industry.
What are the main pathways this pollutant takes to enter into the Salish Sea?
Urban runoff, septic systems, sewer systems, industrial waste, maritime industry.
Why is this pollutant important to know about?
“Endocrine effects on water-based organisms/animals & they bypass wastewater treatment plants and typical filtration methods.”
“Higher concentration and detection frequency.”
“Potentially a huge problem but little is known about them.”
More information about this pollutant
PFAS have been produced and used in industries globally since around the 1940s, and can be found in food packaging, commercial household products, stain- and water- repellent fabrics, nonstick products, waxes, cleaning products, fire-fighting foams, and even in drinking water. They are known to be very persistent and can accumulate both in the environment and within the human body since they do not break down. There is evidence that PFAS can cause adverse health effects in animals including reproductive, developmental, liver and kidney, and immunological problems. While certain PFAS are no longer manufactured in the US, they can still enter the US from other countries in products such as carpet, apparel, textiles, and paper and packaging (“Basic Information on PFAS”, n.d.).
Pesticides, Fungicides, and Herbicides
Where do these pollutants originate from?
Household or lawn care products, manufacturing/industry, agriculture.
What are the main pathways these pollutants take to enter into the Salish Sea?
Urban runoff, industrial waste, agricultural runoff.
Why is this pollutant important to know about?
“Reduces expected life of sea-based organisms, come from non-point sources so very difficult to regulate/monitor/control.”
“Higher concentration and detection frequency.”
More information about these pollutants
Pesticides are a wide category of organic pollutant, and include insecticides, fungicides, and herbicides. These products are often used to kill pests such as weeds, fungi, and insects. However, pesticides can also get into the environment and contaminate soil, water, and vegetation (Aktar et al., 2009). Some are highly toxic to non-target organisms, such as fish, birds, beneficial insects, and plants, and others can create other stressors in the ecosystem such as devegetation (“Herbicides,” n.d.). One well-known pesticide is dichlorodiphenyltrichloroethane (DDT), a synthetic chlorinated aromatic hydrocarbon. DDT was used as an insecticide and helped fight insect-borne diseases such as malaria and typhus. It was also used in agriculture as well as in homes and gardens. As a persistent organic pollutant, DDT can persist in the environment for very long periods of time and can accumulate in fatty tissues and be biomagnified. It is known to lead to tumors and reproductive issues in fish and other organisms. DDT is no longer used in the US, and is generally only used now in other countries for malaria control (“DDT- A Brief History and Status”, n.d.).
6-PPD-quinone
Where does this pollutant originate from?
Tires/rubber.
What are the main pathways this pollutant takes to enter into the Salish Sea?
Storm drains, urban runoff, and roadway runoff.
Why is this pollutant important to know about?
“It causes acute mortality in coho salmon at concentrations found in urban runoff.”
More information about this pollutant
6-PPD is an organic compound often found in tires to make them longer-lasting through reacting with tire-damaging ozone. However, this reaction produces another compound known as 6-PPD-quinone, which is extremely toxic compared to 6-PPD. This compound enters streams when it rains via urban and roadway runoff has been found to kill coho salmon (McQuate, 2020).
Polychlorinated biphenyls (PCBs)
Where does this pollutant originate from?
Manufacturing/ industry.
What are the main pathways this pollutant takes to enter into the Salish Sea?
Urban runoff, industrial waste.
Why is this pollutant important to know about?
“It is still found in food we eat from fish to shellfish to seaweed. It bioaccumulates and is found in Orca whales, too, and bears in Alaska have also had PCB exposure due to fish diet.”
“It is regulated but it is persistent.”
“They are very abundant in marine organisms, degrade extremely slowly, and can biomagnify.”
More information about this pollutant
PCBs, or polychlorinated biphenyls, are a group of manmade chlorinated hydrocarbons that are considered to be persistent organic pollutants. They were produced starting in the 1920s and were used as coolants and lubricants in televisions, refrigerators, and other electrical appliances, and could also be found in carbonless copy paper. Before they were banned in the US in 1979, they were released to the environment through their manufacturing, use, and waste. (“What are PCBs?”, 2021). While PCBs are widespread and persistent in the environment and can still be found globally, they are in fact able to break down. However, the process depends on a variety of factors including the chemical composition of the PCB and the environment it is in. PCBs can biomagnify up the food chain in marine ecosystems and have been found to cause cancer as well as negative effects on the immune, reproductive, nervous, and endocrine systems. (“Learn about Polychlorinated Biphenyls”, n.d.).
Polycyclic aromatic hydrocarbons (PAHs)
Where does this pollutant originate from?
Produced during combustion, fossil fuels (e.g. oil spills).
What are the main pathways this pollutant takes to enter into the Salish Sea?
Storm drains/ urban runoff, roadway runoff, air particulates.
Why is this pollutant important to know about?
“They are in road run-off, fossil fuels — uncombusted, oil spills.”
More information about this pollutant
PAHs include over 100 different organic compounds, both naturally-occurring and anthropogenic, and are considered to be persistent organic pollutants. They can be found naturally in fossil fuels such as coal, crude oil, and gasoline and are also produced through the incomplete burning of organic matter including the previously mentioned fossil fuels as well as wood and food (Maliszewska-Kordybach, 1999). PAHs can be transported into the environment by air, and some PAHs and mixtures of PAHs have been found to cause cancer, reproductive problems, and weakened immune systems in organisms (“Polycyclic aromatic hydrocarbons,” n.d.).
Hexabromocyclododecanes (HBCDs)
Where does this pollutant originate from?
Household or lawn care products, manufacturing/ industry.
What are the main pathways this pollutant takes to enter into the Salish Sea?
Thermal insulation for construction industry, electrical appliances, furniture.
Why is this pollutant important to know about?
“It is persistent in the environment, bioaccumulative and it is a probable health risk for marine animals.”
More information about this pollutant
HBCDs are brominated organic compounds often used as flame retardants in electrical devices and appliances, upholstery fabrics, expanded polystyrene foam, and thermal insulation materials. They are toxic to wildlife including aquatic organisms, likely bioaccumulate, and present developmental and reproductive concerns for human health (Covaci et al., 2006).
Polybrominated Diphenyl Ethers (PBDEs)
Where does this pollutant originate from?
Manufacturing/ industry, manufactured materials from electrical appliances (e.g. computers, refrigerators, furniture).
What are the main pathways this pollutant takes to enter into the Salish Sea?
Storm drains/ urban runoff, e-waste in landfills.
Why is this pollutant important to know about?
“They are no longer used in the US and Canada but they are persistent and continue to be a risk to ocean health and marine life.”
More information about this pollutant
PBDEs are a class of halogenated organic compounds that are used as flame retardants in consumer goods. They have been produced since the 1960s and are often found in electrical appliances and devices, such as toasters and televisions, as well in textiles, furniture padding, and construction materials. Industrial sites and household waste are both significant sources of PBDEs that are released into the environment (Siddiqi et al., 2003). As persistent organic pollutants, they have been found to accumulate in coastal and marine environments as well as in air, soil, sediments, humans, and wildlife (including marine life). Not much is actually known about their toxicity, but it is thought that they could be associated with tumors, neurodevelopmental toxicity, and thyroid hormone imbalance, and are also likely endocrine disruptors (“What are PBDEs?,” 2013).
Local Solutions
While this may all seem like a lot, luckily there are experts working to better understand these impacts, reduce their effects on the environment, and clean up damage that has been done. Here are some organizations working to support our local watershed:
References
Aktar, W., Sengupta, D., & Chowdhury, A. (2009). Impact of pesticides use in agriculture: Their benefits and hazards. Interdisciplinary Toxicology, 2(1), 1–12. https://doi.org/10.2478/v10102-009-0001-7
Covaci, A., Gerecke, A. C., Law, R. J., Voorspoels, S., Kohler, M., Heeb, N. V., Leslie, H., Allchin, C. R., & de Boer, J. (2006). Hexabromocyclododecanes (hbcds) in the environment and humans: A review. Environmental Science & Technology, 40(12), 3679–3688. https://doi.org/10.1021/es0602492
Environmental Protection Agency. (n.d.). Addition of Hexabromocyclododecane (HBCD) Category to TRI List Final Rule. EPA. https://www.epa.gov/toxics-release-inventory-tri-program/addition-hexabromocyclododecane-hbcd-category-tri-list-final.
Environmental Protection Agency. (n.d.). Basic Information on PFAS. EPA. https://www.epa.gov/pfas/basic-information-pfas.
Environmental Protection Agency. (n.d.). DDT- A Brief History and Status. EPA. https://www.epa.gov/ingredients-used-pesticide-products/ddt-brief-history-and-status.
Environmental Protection Agency. (n.d.). Herbicides. EPA. https://www.epa.gov/caddis-vol2/caddis-volume-2-sources-stressors-responses-herbicides.
Environmental Protection Agency. (n.d.). Learn about Polychlorinated Biphenyls (PCBs). EPA. https://www.epa.gov/pcbs/learn-about-polychlorinated-biphenyls-pcbs.
Environmental Protection Agency. (n.d.). What is Endocrine Disruption? . EPA. https://www.epa.gov/endocrine-disruption/what-endocrine-disruption.
Environmental Protection Agency. (n.d.). What is the Endocrine System? . EPA. https://www.epa.gov/endocrine-disruption/what-endocrine-system.
Maliszewska-Kordybach, B. (1999). Sources, Concentrations, Fate and Effects of Polycyclic Aromatic Hydrocarbons (PAHS) in the Environment. Part A: PAHS in Air. Polish Journal of Environmental Studies, 8(3).
McQuate, S. (2020, December 3). Tire-related chemical is largely responsible for adult coho salmon deaths in urban streams. UW News. https://www.washington.edu/news/2020/12/03/tire-related-chemical-largely-responsible-for-adult-coho-salmon-deaths-in-urban-streams/.
NOAA. (2013, June 1). What are PBDEs? NOAA’s National Ocean Service. https://oceanservice.noaa.gov/facts/pbde.html.
NOAA. (2021, March 5). What are PCBs? NOAA’s National Ocean Service. https://oceanservice.noaa.gov/facts/pcbs.html.
Polycyclic aromatic hydrocarbons (PAHS). PAH — Washington State Department of Ecology. (n.d.). https://ecology.wa.gov/Waste-Toxics/Reducing-toxic-chemicals/Addressing-priority-toxic-chemicals/PAH.
Siddiqi, M. A., Laessig, R. H., & Reed, K. D. (2003). Polybrominated diphenyl ethers (PBDEs): NEW Pollutants-Old Diseases. Clinical Medicine & Research, 1(4), 281–290. https://doi.org/10.3121/cmr.1.4.281
UN Environment Programme. (n.d.). What are POPs? Stockholm Convention. http://www.pops.int/TheConvention/ThePOPs/tabid/673/Default.aspx.
