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Images: How Does Toxic Mercury Get into Fish?

WHOI biogeochemist Carl Lamborg studies how various forms of mercury get into and cycle through the ocean and freshwater lakes and rivers, focusing particularly on the toxic form of mercury that accumulates in fish.
(Photo by Danielle Fino, Woods Hole Oceanographic Institution)

Carl Lamborg used sediment traps to try to find the source of toxic monomethyl mercury (MMHg) in low-oxygen zones of the ocean.The tube-shape traps were suspended at depths above, in, and below the low-oxygen zone and left in place for four days. Particles drifting down through the water fell into the traps. After recovering the traps, Lamborg analyzed the material in them for the presence of elemental mercury and monomethyl mercury. He found very little of either, leaving the source of MMHg in the low-oxygen zone a mystery.
(Illustration by Jack Cook, Woods Hole Oceanographic Institution)

The long blue drogue at the bottom of a sediment trap line helps keep the line, and the traps attached to it, vertical in the water. The orientation is important so the traps gather material falling from the ocean above them. (Photo by Tyler Goepfert, Woods Hole Oceanographic Institution)

WHOI biogeochemist Carl Lamborg (right) helps deploy sediment traps to be suspended at three depths to catch particles drifting down through the water. Lamborg later analyzed the captured material for the presence of mercury. (Photo by Tyler Goepfert, Woods Hole Oceanographic Institution)