Humans Have Tripled Mercury Levels in the Ocean

Pollution may soon overwhelm deep seas' ability to sequester mercury, which builds up in tuna and other predatory fish

Aug 6, 2014 | By Anne Casselman and Nature magazine

Mercury levels in the upper ocean have tripled since the beginning of the Industrial Revolution, and human activities are to blame, researchers report today in Nature.

Although several computer models have estimated the amount of marine mercury, the new analysis provides the first global measurements. It fills in a critical piece of the global environmental picture, tracking not just the amount of mercury in the world's oceans, but where it came from and at what depths it is found.