Associated Press
A dioxin find at the bottom of Michigan's Saginaw River could be the highest level of such contamination yet discovered in U.S. rivers and lakes, according to a federal scientist involved in cleanup efforts downstream from a Dow Chemical Company plant.
A crew testing the Saginaw and Tittabawassee rivers discovered the sample, which measured 1.6 million parts of dioxin per trillion parts of water, the Saginaw News and the Detroit News reported last week.
That level is about 20 times higher than any other find recorded in the U.S. Environmental Protection Agency archives.
"There may be more surprises out there," said Milton Clark, a health and science expert for the EPA. "I'd be surprised if there's not more surprises out there."
State guidelines require corrective action on contamination above a thousand parts per trillion.
Dioxins are toxic byproducts of the manufacture of chlorine-based products, and some have been linked to cancer and other health problems.
Dow is already removing three dioxin concentrations along a six-mile (ten-kilometer) stretch of the Tittabawassee, a Saginaw River tributary that winds through Dow's plant in Midland, Michigan.
The company also plans to remove the latest find, Dow spokesperson John C. Musser said.
"We don't believe there's any imminent or significant human health or environmental threat," Musser said.
Michigan health officials were worried enough about last week's announcement that they extended a fish consumption advisory already in effect for the Tittabawassee River to include the entire Saginaw River and a portion of Lake Huron's Saginaw Bay, where both rivers' water ends up.
The advisory warns against eating carp, catfish, and white bass—fish that feed near the riverbed where contaminants are buried. It also suggests women of childbearing age and children avoid eating certain other types of fish.
Copyright 2007 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
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