New contamination concerns
As researchers search for answers, health officials continue to learn more about just how extensively PFAS has contaminated Michigan’s fish and wildlife.
Just last month, Wisconsin officials notified residents to limit consumption of Lake Superior smelt after learning the fish were contaminated with PFOS. That’s troubling news for Michigan, too.
Lake Superior smelt are not on Michigan’s fish consumption advisory list, and the state hasn’t tested them for PFAS compounds.
But “we consider the Wisconsin data to be rather reliable,” said Marcus Wasilevich, PFAS response coordinator at the Michigan Department of Health and Human Services, in part because Michigan and Wisconsin researchers obtained similar results when they tested other Lake Superior species.
Michigan regulators are holding off on issuing a smelt advisory of their own as they make plans to collect samples this spring from lakes Superior, Michigan and Huron, and some inland waters. If Michigan’s test results track Wisconsin’s, an advisory could follow.
The news out of Wisconsin is concerning, said Amy Trotter, executive director of the Michigan United Conservation Clubs, whose members include many hunters and anglers. But she agrees with the state’s decision to conduct its own testing before alerting anglers.
“We don't want (needless consumption advisories) to ever be a deterrent from hunting and fishing and taking advantage of the outdoors,” she said.
But the presence of high PFOS levels in a fish relatively low on the food chain, swimming in a large water body where contamination should theoretically be more diffuse, raises new questions about how the chemicals move through ecosystems.
Many environmental toxins grow more concentrated in animals’ bodies as they move up the food chain, in a process called bioaccumulation. Contaminated insects or minnows pass the toxins on to small fish that eat them. Those small fish, in turn, pass the contamination onto bigger species that prey upon them.
But Wisconsin’s discovery of high levels in smelt, a species low on the food chain, indicates that PFAS “doesn't seem to follow the same rules,” Wasilevich said.
Continued sampling and research, Trotter said, is crucial to better understanding where else PFAS has contaminated fish and wildlife, and how species respond once the poison stops flowing. The current MDHHS budget for fish, wild game and home-raised food testing is about $1.2 million. Environmental advocates contend Michigan needs more money and additional lab capacity to build a more robust testing regime.
“We definitely need more research,” Trotter said, “not just on game fish and deer, but the whole suite: birds, reptiles, amphibians.”
A mixed bag
There’s good news and bad news in what researchers know so far.
Fish in the 900-square-mile Huron River watershed are so contaminated, state officials warn against eating even a single serving from an area that spans five counties. But recent sampling indicates fish may quickly flush PFAS from their systems once the chemicals are removed from the water, said Daniel Brown, watershed planner for the Huron River Watershed Council.
After Tribar Manufacturing, a Wixom automotive supplier responsible for much of the Huron River’s contamination, installed filters to clean its effluent, concentrations in some fish samples dropped to about half of previous levels, Brown said.
The fish are still too toxic to eat, but Brown said the test results are “encouraging.” If the trend continues, he hopes Huron River anglers may soon be able to resume eating their catch.
Hoverman, of Purdue, cautioned that not every contaminated water body will heal so quickly once contamination stops flowing. Clark’s Marsh, for example, is relatively stagnant, meaning tainted water will be slow to drain away. And it’s unclear whether PFAS could persist in sediment after the water is clean.
Even the Huron’s promising news, he said, should come with a dose of caution. The PFAS that plagued the river hasn’t disappeared. It has merely flushed out to Lake Erie, after which it will travel to Lake Ontario and, eventually, the Atlantic Ocean. PFAS will eventually be present at low levels in all of the world’s waterways, he said, and researchers simply don’t know how that will affect the species that live there.
“It's really that constant low level of exposure that we need a lot more research on,” he said.
Back in Oscoda, Hock said he’s seen enough research to know the contamination at Wurtsmith needs to be cleaned up — for his sake and that of the fish and deer.
But it’ll be years before the Air Force completes a cleanup plan for Wurtsmith, and years more before cleanup is complete. So Hock has given up agonizing over all the ways it could be hurting him.
“This PFAS stuff is in virtually everything you touch,” he said. “Do I want to live in fear, or do I want to live?”
The Link LonkFebruary 16, 2021 at 12:28AM
https://ift.tt/2Nttith
PFAS is in fish and wildlife. Researchers prowl Michigan for clues. - Bridge Michigan
https://ift.tt/35JkYuc
Fish
No comments:
Post a Comment