Study shows three times more mercury in upper ocean since Industrial Revolution

Researchers led by Carl Lamborg at the Woods Hole Oceanographic Institution found that mercury from human activity (primarily atmospheric emissions produced by coal burning and cement production, as well as gold mining) have resulted in ocean waters down to 100 meters depth being enriched in the toxic element up to 3.5 times the background level caused by the natural breakdown, or weathering, of rocks on land. (Illustration by Jack Cook, Woods Hole Oceanographic Institution)
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