more than twice as much mercury in environment found

The finding doesn’t indicate a greater risk to human health; scientists already know how much mercury most people are exposed to. But it does show how tighter regulations over the past 4 decades have lowered the total amount of mercury emitted to the global environment—even as some industries in the developing world continue to expand.

Mercury is a dangerous neurotoxin, and it is most harmful when microbes convert the element into a compound called methylmercury. This form of the metal accumulates in food webs, concentrating in fish, which is how most people are exposed. Researchers in developed countries typically know how much methylmercury is in fish, which they use to set consumption advisories.
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