New research from the University of Michigan and the
University of Hawaiʻi at Mānoa School of Ocean and Earth Science and Technology
combines biogeochemistry and direct marine ecology observations to show how the
global mercury cycle is colliding with ocean fish—and the human seafood
supply—at different depths in the water.
Mercury—a common industrial toxin—is carried through the
atmosphere before settling on the ocean and entering the marine food web.
Mercury accumulation in the ocean fish that is eaten tends to take place at
deeper depths, scientists found, in part because of photochemical reactions
that break down organic mercury in well-lit surface waters. More of this accessible
organic mercury is also being generated in deeper waters.