The Legacy of the Mercury Mines

The most dangerous form of mercury is not liquid mercury, the well-known quicksilver valued by miners, but a compound called methylmercury. When mercury sits in the sediments of oxygen-poor waters of lakes and wetlands, bacteria produce this potent neurotoxin from the mercury. It is taken up by algae, then it concentrates as it moves from algae, to zooplankton, to prey fish, to predator fish, and finally to humans. To protect the public from the dangers of eating contaminated fish, warning signs near local ponds and reservoirs instruct anglers not to eat their catch.
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