Mercury in Fish Predicted To Soar
Researchers have suspected for some time that emissions from coal-fired power plants in energy-hungry, rapidly industrializing China and India were a major environmental threat: according to the study, over the past two decades, emissions during the combustion of coal, which contains elemental mercury, have declined in North America and Europe, but “increased substantially” in East Asia and India. But exactly how airborne mercury from Asia has been entering deep ocean fish caught thousands of miles away has not been understood until now.
“Mercury researchers typically look skyward to find a mercury source from the atmosphere due to emissions from land-based combustion facilities,” USGS scientist and coauthor David Krabbenhoft said in a statement. “In this study, however, the pathway of the mercury was a little different. Instead, it appears the recent mercury enrichment of the sampled Pacific Ocean waters is caused by emissions originating from fallout near the Asian coasts. The mercury-enriched waters then enter a long-range eastward transport by large ocean circulation currents.”
In mid-depth ocean, the study showed, decomposing algae interact with mercury to form lethal methylmercury that enters the food chain, eventually contaminating tuna and other food fish.
via Mercury in Fish Predicted To Soar | Environmental Working Group.