According to a pair of recent scientific studies, microplastics and a class of toxic chemicals known as polyfluoroalkyl substances (or PFAS) are becoming increasingly prevalent in the world’s oceans and have begun to contaminate the global seafood supply.
According to a July 2020 study published in the scholarly journal Environmental Science & Technology, PFAS—a family of potentially harmful chemicals used in a range of products including carpets, furniture, clothing, food packaging, and nonstick coatings—have now been found in the Arctic Ocean. This discovery worries scientists because it means that PFAS can reach any body of water anywhere in the world and that such chemicals are likely present in our water supply. Meanwhile, researchers at the QUEX Institute, a partnership between the University of Exeter and the University of Queensland, have found microplastics in crabs, oysters, prawns, squid, and sardines sold as seafood in Australian markets, findings also first published in Environmental Science & Technology and covered by Medical News Today in August 2020. As Robby Berman reported for Medical News Today, the new findings suggest that microplastics—small pieces of plastic, less than five millimeters in length (about the size of a sesame seed) that are a consequence of plastic pollution—have “invaded the food chain to a greater extent than previously documented.”
The presence of PFAS in the Arctic Ocean is concerning for many reasons. As Daniel Ross reported in an October 2020 article for Truthout, PFAS chemical exposure is known to have serious impacts on human health as a cause of cancer, liver damage, thyroid problems, and increased risk of asthma. People with elevated levels of PFAS chemicals are twice as likely to develop a severe form of COVID-19 since these chemicals are endocrine disruptors.
Because the Arctic Ocean is so remote from human population centers, exactly how these chemicals may have reached these waters is also a deeply concerning question. As Ross pointed out in the Truthout article, “Emerging research suggests that one important pathway is through the air and in rainwater” rather than through ocean circulation. Discovering the pathways through which these “forever chemicals” are contaminating isolated areas is important for regulators as they attempt to remove these chemicals from the environment. Atmospheric spread may make removal considerably more difficult.
Like PFAS compounds being found in Arctic waters, the discovery of microplastics in popular forms of seafood is truly alarming.
Microplastics are less than five millimeters in length, and nanoplastics are less than one hundred nanometers in length. According to the QUEX study, their small size allows these microplastics to spread through “airborne particles, machinery, equipment, and textiles, handling, and [. . .] from fish transport.” The research team at Exeter and Queensland found microplastics present in all of the seafood samples they studied, with polyvinyl chloride being found in every case. The study’s lead author, Francisca Ribeiro, told Medical News Today that, for an average serving, a seafood eater could be exposed to “approximately 0.7 milligrams (mg) of plastic” when ingesting oysters or squid, and “up to 30 mg of plastic” when eating sardines. For comparison, note that a grain of rice weighs approximately 30 mg.
As Medical News Today reported in its August 29, 2020 article on the study, approximately 17 percent of the protein that humans consume worldwide is seafood. The findings suggest that “people who regularly eat seafood are also regularly eating plastic.” According to Tamara Galloway, a researcher from Exeter University who is one of the study’s co-authors, “We do not fully understand the risks to human health of ingesting plastic, but this new method [used in the study for detecting selected plastics] will make it easier for us to find out.”
In October 2020 the Guardian reported that at least 14 million tons of microplastics are likely sitting on the ocean floor—“more than 30 times as much plastic at the bottom of the world’s ocean than there is floating at the surface,” according to an estimate based on new research, Graham Readfearn reported.
As the Guardian report noted, “Stemming the tide of plastic entering the world’s waterways and ocean has emerged as a major international challenge.” In September 2020, leaders from more than seventy countries signed a voluntary pledge to reverse biodiversity loss which included, as a goal, stopping plastic entering the ocean by 2050. The United States, Brazil, China, Russia, India, and Australia did not sign that pledge.
Media coverage of both the study on microplastics in seafood and the research on PFAS in the Arctic Ocean has predominantly come from independent news sources as well as journals and websites aimed at members of the scientific community. Of the articles covering the presence of PFAS in Arctic waters, many simply summarize the findings of the research. However, Truthout and Chemical & Engineering News each took their coverage further by including professional opinions on the significance of the study and addressing remedies to the problem.
Lack of corporate news attention could stem from the idea that the research findings are nothing new or simply confirm what many have previously assumed. However, the significance of these PFAS pollutants potentially being airborne deserves greater recognition because this poses greater challenges for abatement efforts. The Exeter and Queensland researchers’ findings about micro- and nano-plastics in seafood likewise require publicizing despite the findings confirming certain earlier assumptions, because the evidence they present could prove crucial in mobilizing political will to address an issue that is barely visible and that few people recognize as a serious problem. Outside of coverage by the Guardian, no major news outlet has paid attention to the topic of microplastics in seafood.
Robby Berman, “Study Found Plastic in Every Seafood Sample It Analyzed,” Medical News Today, August 29, 2020.
Graham Readfearn, “More Than 14m Tonnes of Plastic Believed to be at the Bottom of the Ocean,” The Guardian, October 5, 2020.
Daniel Ross, “More Traces of Cancer-Causing PFAS in Arctic Raise Alarm over Global Spread,” Truthout, October 18, 2020.
Sharon Lerner, “PFAS Chemical Associated with Severe COVID-19,” The Intercept, December 7, 2020.
Student Researchers: Eduardo Amador, Kolby Cordova, and Natalia Fuentes (Sonoma State University)
Faculty and Community Evaluators: Peter Phillips (Sonoma State University) and Polette Gonzalez
Illustration by Anson Stevens-Bollen.