We know what the past and present hold, which is that the EPA regulations have a huge benefit for the ecosystem and the humans that eat that fishīarber told ThinkProgress that he and his colleagues always had a feeling that the mercury levels that they were seeing in the 1970s weren’t from natural causes - but what surprised him, he said, is the rate at which mercury levels in fish decreased. They were not from volcanoes they were from anthropogenic contamination.” “That clearly indicates that the mercury levels that we found back in the ’70s were not natural. “We are seeing the mercury come down as mercury pollution has been reduced in U.S. But the sharp drop in mercury levels, Barber said, confirms that high levels in the 1970s were not natural background levels, and were exacerbated by mercury pollution from humans. The oceans, conventional wisdom said, were simply too large - anthropogenic pollution, either from air pollution or waste disposal, could not impact something so vast. In the 1970s, the study continues, it was widely accepted that elevated mercury levels in oceans were not a result of human activity, and instead represented natural background levels - mercury spewed out by underwater volcanoes or some other naturally occurring phenomenon. Looking at samples of bluefish tissue from 2011, and comparing it to samples from 1972, Barber and his colleagues saw a sharp reduction in mercury levels - a drop that mirrored reductions of mercury in “atmospheric deposition, riverine input, sea water, freshwater lakes and freshwater fish across northern North America,” according to the study. Past studies have shown a tight correlation between mercury emitted from coal plants and mercury found in fish, Barber explained. But healthier bluefish aren’t just a public health win - they also add increased economic benefit to coastal communities and the fishing industries that depend on them. Once in water, mercury accumulates throughout the marine food chain, with predators eating mercury-tainted food, causing the mercury to build up in their biological tissues.īluefish, one of the most popular species for commercial and recreational fishing along the East Coast, is a top-level predator known for harboring especially high levels of mercury - so high that the Natural Resources Defense Council recommends limiting consumption of bluefish by pregnant women and children to three servings or less per month. Today, coal-fired power plants are the primary sources of mercury emissions in the United States - toxic pollutants that damage air quality and contribute to ocean pollution once they eventually settle in bodies of water through precipitation. “Here is an example of rules that EPA put in place regarding mercury, and now 30 years later we see these rules potentially have a huge impact on human health and economics.”ĮPA regulations and the Canadian regulations have had a relatively huge impact on coastal ocean fishīeginning in the 1990s, the EPA began more tightly regulating mercury, banning the compound from batteries and controlling the transportation of mercury compounds used in industry. “This shows that the regulations and the Canadian regulations have had a relatively huge impact on coastal ocean fish,” Richard Barber, professor emeritus of biological oceanography at Duke University and co-author of the study, told ThinkProgress.
Mercury levels in Atlantic bluefish have been steadily declining over the past four decades - an indication that federal regulations on mercury pollution are working.Īccording a new study from the National Oceanic and Atmospheric Administration’s Center for Fisheries and Habitat Research, mercury levels in bluefish caught along the mid-Atlantic coastline have dropped 43 percent over the last 40 years, with an average reduction of 10 percent per decade.
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