Environment
10:49 am
Thu May 5, 2011

Aircraft chemical found in Great Lakes fish

New research finds that fish in the Great Lakes are contaminated with a chemical used in aircraft hydraulic fluids.

Researcher Amila DeSilva works for Environment Canada, which is like the EPA in the U.S.

She says there have been studies on a number of perflourinated chemicals. They’re used to make textiles, upholstery, paper, and many other things. Studies have shown these types of chemicals can have toxic effects in humans. But not much is known about a chemical called perfluoroethylcyclohexanesulfonate - or PFECHS for short.

DeSilva says no one has really studied whether it's toxic.

She wanted to see if PFECHS was in the environment, so she and her colleagues sampled water and fish in the Great Lakes, specifically lake trout and walleye:

“We were really, really surprised to find it in fish. Because, just based on the structure and our chemical intuition we thought, ‘okay, it would be more likely to be in water than in fish’ so when we found it in fish, when you find anything in fish, it’s a whole other ballgame because humans consume fish.”

DeSilva says other perflourinated acids are endocrine disruptors. That means they create hormone imbalances in humans, and they have other toxic effects. She says once these chemicals are released into the environment they don’t degrade, they just build up. That’s why use of some chemicals in this class is highly restricted in the U.S. and Canada.

“PFECHS on the other hand is still approved for use, and mainly because its specialized use in aircraft hydraulic fluid, was believed to not really lead to environmental contamination, it was thought to be contained.”

DeSilva says the company 3M was the largest producer of PFECHS, until it stopped making the chemical 2002. She says Environment Canada believes it is still being made elsewhere, and is still in use on military bases.

DeSilva says her team’s research shows PFECHS contamination may be as widespread as the other perflourinated chemicals. She says the next step is to see whether PFECHS moves up the food chain - to find whether it builds up in people who eat contaminated fish.

-Julie Grant for The Environment Report