Study: ‘Chemicals Are Forever’ Barely Found in Arctic Fish in Alaska
UAF CFOS graduate Carolyn Hamann shows saffron cod caught in small nets during LTFP field work near Beaufort Beach in Prudhoe Bay. (Photo by Kyle Gatt/UAF)
Fairbanks, Alaska (UAF) – A new study has found minute levels of chemical contamination in a small sample of Arctic coastal fish species, an encouraging finding for populations that depend on them for subsistence food.
The study looked for the presence of PFAS, which is short for per- and polyfluoroalkyl substances, which are a broad class of harmful synthetic chemicals that do not biodegrade naturally.
This property has earned them the nickname “forever chemicals” because they persist and accumulate in the environment, polluting sites throughout Alaska and around the world.
“Once these materials are in the water, it’s pretty much impossible to get out of, and they can build up in the tissues of fish and wildlife,” said Kevin Fraley, a fisheries ecologist with the Wildlife Conservation Society and lead author of the study. . “In Alaska, we eat a lot of wild foods, which makes it very interesting to know how much is there.”
The study analyzed muscle tissue from fish species important for subsistence fishing.
They were collected during separate, long-term research projects conducted by the University of Alaska Fairbanks and the Wildlife Conservation Society.
The samples, collected near Kotzebue and Prudhoe Bay, were tested for 24 PFAS compounds as well as total mercury levels.
Alaska does not have health guidelines for PFAS contamination of fish.
Other states have advised different measures at pollution levels from 9 to 47 micrograms per kilogram.
All fish tested from samples from the Chukchi and Beaufort Seas were well below those levels.
Dolly Varden at both sites was virtually free of chemicals, with only trace amounts of one contaminant present in the Beaufort sample.
The highest levels detected were in the Beaufort Sea whitefish, which had 2.8 µg/kg PFAS.
Other species tested included Arctic flounder, saffron cod, econo (also known as shepherd’s fish), humpback whitefish, and lesser sisko.
These levels contrast dramatically with some Arctic sites in Canada and Europe, where fish samples had PFAS levels in excess of 30 μg/kg in some locations.
Mercury levels were also low in the Alaskan samples, with all species tested well below the limits specified in Alaska’s fish consumption guidelines for vulnerable groups, which include children and pregnant women.
“Given the importance of Alaskan fisheries resources, it is great to see that the fish examined as part of this study had minimal levels of contaminants,” said Trent Sutton, a fisheries biologist at the UAF College of Fisheries and Oceanography. Investigator in the long-term nearshore fish monitoring program in the Beaufort Sea.
Besides Sutton, one of the contributors to the study was Caroline Hamann, who graduated from UAF this year with a master’s degree in fisheries.
For this project, Hamann led the sampling effort for fish populations in Prudhoe Bay through the Beaufort Sea Watch Program.
The study was funded by the Western Division of the American Fisheries Association, Alaska Hilcorp, and the National Park Service.
(tags for translation)Juneau