PORTLAND, Maine (AP) - A new study says a former open pit mine that's now a federal Superfund site in Brooksville, Maine, has caused elevated levels of toxic heavy metals in the surrounding coastal estuary.
The Dartmouth University study focusing on the Callahan Mine found elevated levels of copper, zinc, cadmium and lead in the sediment, water and small killifish.
Researchers said levels of toxic metals in small killifish were high enough to have an impact on larger fish that feed on them, increasing the potential for harm to humans. They also found uneven concentrations of heavy metals, suggesting a continuing source of contamination that's yet to be identified.
The Callahan mine closed in 1972, and Maine is currently reviewing mining regulations.
The study appears in Archives of Environmental Contamination and Toxicology.
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