Scientists have discovered bacteria living in Antarctic sea ice that could play a role in mercury contamination of fish, birds, and other marine species.
The bacteria, Nitrospina, can transform mercury found in sea ice — originating from sources such as coal-fired power plants — into the more toxic methylmercury. The heavy metal pollutant—which impacts brain development and can cause mental and physical ailments—accumulates in higher concentrations in marine life as it moves up through the food chain. The findings were published Monday in the journal Nature Microbiology by scientists at the University of Melborne, the U.S. Geological Survey, and Lawrence Livermore National Lab. John Moreau, a geomicrobiologist at the University of Melbourne who helped lead the study, said in a statement that the findings beg further study into the sources and behavior of mercury in the oceans, “particularly in a warming climate and when depleted fish stocks means more seafood companies are looking south.”
Antarctic sea ice.