West Virginia regulators say a contaminant that Brooke County fishermen spotted in Buffalo Creek is a clay-like substance used in natural gas drilling.
Department of Environmental Protection spokeswoman Kathy Cosco says the bentonite also was found this week in the Ohio River. She says it may have come from a western Pennsylvania gas well.
The Intelligencer says exposure to bentonite may cause skin, eye, gastrointestinal or respiratory irritation.
The DEP will test samples to see what other chemicals might be present.
Water departments along the river are taking precautions.
Wheeling Public Works Director Russell Jebbia says the amount of bentonite seems to be so small that it's unlikely to have any impact.
Spokesman Kevin Sunday says the Pennsylvania Department of Environmental Protection was unable to find the substance.
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