Researchers recently identified eight chemicals in different Puget Sound waters found at “concerning levels” for fish and other marine life, requiring more investigation.
They include two that come from tires or other vehicle parts; a pair of herbicides, one of which is used to control algae and weeds; Venlafaxine, an antidepressant drug; and PFOS and two compounds found in plastics.
That’s according to a University of Washington press release out yesterday.
It said that all totaled, researchers using a “‘non-targeted’ approach” in 2018 sampled 205 different chemicals, including 64 never seen before in the inland sea’s waters, in 18 diverse shoreside locations from Port Townsend to Everett to Hood Canal to Olympia from April through October.
Sites included polluted waterways such as Seattle’s Smith Cove and the Thea Foss Waterway in Tacoma, but also a “relatively clean” spot halfway down the canal.
“With such a wide range, we hoped to see a link between contamination and land use,” said coauthor Zhenyu Tian, a research scientist at UW’s Center for Urban Waters.
Previous studies looked at known chemicals in Puget Sound, but this one used a new technique, high-resolution mass spectrometry, to confirm 75 of the 205 compounds, and those included families you would expect to see — best illustrated by 2016 The Late Show skit with Sammy the (Stoned) Salmon — alongside a suite of other “contaminants of emerging concern,” or CECs — pesticides, herbicides and chemicals in tires.
Particles wearing off tires are also being eyed as suspect in why coho are dying in urban streams before they can spawn.
Of note, the octet were found in specific hot spots, and they didn’t always turn up in repeated sampling.
According to C. Andrew James, another Center for Urban Waters researcher and coauthor, their goal is to identify what compounds matter most from “a biological perspective — how a fish or a shellfish will react” and better understand why those eight are where they are.
Their work was published in late December in the journal Environmental Science & TechnologyCoauthor Edward Kolodziej, a UW associate professor, notes that a “huge fraction” of what Pugetropolites consume ends up flushing down the rivers into the Whulge.
“Everyone thinks chemicals hit the ocean and disappear because there’s so much water in the ocean that the concentrations go way down,” Kolodziej said in the press release. “But if you took the concentration of a chemical in wastewater effluent or storm water, it’s not like you can just divide by total water volume of Puget Sound, and that’s the concentration you’d detect in Puget Sound. The concentration in the nearshore is a lot higher because there hasn’t been enough time for mixing to occur. So exposure levels for aquatic organisms in the nearshore can be much higher than you might expect.”
Nearshore environments are very important habitat for young salmon and their forage.
A separate 2018 study by federal and university researchers on CECs not screened out by wastewater treatement plans found that exposure to medications “may result in early mortality or an impaired ability to compete for limited resources” among, most notably, Chinook.