Mercury levels have tripled in world's oceans since Industrial Revolution

About two-thirds of the world's ocean mercury resides in water that is shallower than 3,300 feet, however, which suggests that toxic sources of mercury have been gradually polluting ocean water for centuries. And over time, this mercury is slowly sinking and spreading, resulting in fish coming into contact with it and absorbing it into their tissue.

"Nobody's attempted to do a more comprehensive overview of all the oceans and get an estimate of total mercury in the surface and some deeper waters before," said David Streets, an energy and environment policy scientist at Argonne National Laboratory in Lemont, Illinois, to Scientific American. Streets was not involved in the study.
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