Huge New Mercury Pathway to Our Oceans Unearthed

We were surprised by how much mercury we detected in Waquoit Bay,” said Lamborg. “We thought, ‘this can’t be right,’ and went back to the lab to check the results several times. We realized that if these numbers are right, then something unusual must be going on.”

After checking and rechecking their methods and data, the research team found total mercury concentrations that were an order of magnitude (at least 10 times) higher than what should be deposited by simple outfall from the atmosphere, and substantially more mercury than could flow in from local streams. The source had to be submarine groundwater pushing mercury out from the sediments.

This shocking revelation from a research team from Woods Hole Oceanographic Institution in Woods Hole, MA. They were looking into mercury contamination in Waquoit Bay in Falmouth, MA. Their study was focused on total mercury, not the toxic forms like methyl mercury. But this is still very important because elemental mercury is transformed into its toxic forms by bacteria and other microbes. So it actually may be present in high concentrations in these toxic forms too, but more research will be required to prove or disprove that possibility.

Hg-ATME is focused on mercury emissions and technically this pathway is through the groundwater and not from industrial emissions. But I would suggest that a good portion of that mercury eminated from power plant stacks and other point sources, fell to the ground in precipitous fashion and percolated down into our groundwater table and migrated toward the sea. So, in essence, this is related to mercury emissions.

More excerpts from the UnderwaterTimes.com News Service story follow.

Woods Hole, Massachusetts (Mar 21, 2007 13:06 EST) Researchers from the Woods Hole Oceanographic Institution (WHOI) have found a new and substantial pathway for mercury pollution flowing into coastal waters. Marine chemists have detected much more dissolved mercury entering the ocean through groundwater than from atmospheric and river sources.
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The lead author of the study is Sharon Bone, a former undergraduate summer student fellow and research assistant in the laboratory of WHOI marine chemist Matt Charette. Bone is now a first-year graduate student at the University of California at Berkeley.

The findings were published online on March 21 by the journal Environmental Science and Technology and will appear in a printed issue later this spring.

Mercury pollution comes mostly from industrial emissions to the atmosphere, especially from coal burning. After getting into the air, mercury particles eventually precipitate with rain or snow onto the land or directly into the oceans. Inland deposits of mercury are also weathered and carried to the coast in runoff from streams and rivers, where they accumulate in the sediments that build up along the shoreline.

This very interesting article can be read in its entirety here.