MESSAGE FROM ASSOC PROF PAMELA S EVERS ATTORNEY AT LAW This article has been offered by web posting to UNCW students for educational purposes only Articles posted may have been edited for clarity and format by Pamela S Evers Fish Nationwide Contaminated With Mercury WASHINGTON DC August 24 2009 ENS Scientists found mercury contamination in every fish sampled in 291 streams across the country reports a new study by the U S Geological Survey About a quarter of the fish tested were found to contain mercury at levels exceeding the criterion for the protection of people who consume average amounts of fish established by the U S Environmental Protection Agency More than two thirds of the fish exceeded the U S EPA level of concern for fish eating mammals according to the study released on Friday This study shows just how widespread mercury pollution has become in our air watersheds and many of our fish in freshwater streams said Secretary of the Interior Ken Salazar This science sends a clear message that our country must continue to confront pollution restore our nation s waterways and protect the public from potential health dangers The USGS scientists studied mercury contamination in fish bed sediment and water from 291 streams sampled from 1998 to 2005 Atmospheric mercury is the main source to most of these streams coal fired power plants are the largest source of mercury emissions in the United States but 59 of the streams also were affected by gold and mercury mining Some of the highest levels of mercury in fish were found in the tea colored or blackwater streams in North and South Carolina Georgia Florida and Louisiana areas associated with relatively undeveloped forested watersheds containing abundant wetlands compared to the rest of the country A blackwater stream has a deep slow moving channel that flows through forested swamps and wetlands As vegetation decays in the water tannins are leached out resulting in transparent acidic water that is darkly stained resembling tea or coffee A swamp fed blackwater stream in northern Florida Photo by Tim Ross High levels of mercury in fish also were found in relatively undeveloped watersheds in the Northeast and the Upper Midwest Elevated levels of mercury also were observed in areas of the Western United States affected by mining Mercury a neurotoxin is one of the most dangerous contaminants in U S waters The main source of mercury to natural waters is mercury that is emitted into the atmosphere by coal fired power plants and factories and deposited onto watersheds by precipitation But the USGS says atmospheric mercury alone does not explain the contamination found in the fish in U S streams Naturally occurring watershed features like wetlands and forests help convert mercury to the toxic form methylmercury Methylmercury is taken up by aquatic organisms resulting in the contamination of fish that eat those organisms This study improves our understanding of where mercury ends up in fish in freshwater streams said USGS scientist Barbara Scudder The findings are critical for decision makers to effectively manage mercury sources and to better anticipate concentrations of mercury and methylmercury in unstudied streams in comparable environmental settings Since USGS studies targeted specific sites and fish species the findings may not be representative of mercury levels in all types of freshwater environments across the United States the agency says All 50 states have mercury monitoring programs and 48 states issued fish consumption advisories for mercury in 2006 the most recent year of national scale reporting to the EPA The EPA regulates mercury emissions to air land and water In February the EPA announced that it intends to control air emissions of mercury from coal fired power plants by issuing a rule under the Clean Air Act Click here to view the USGS report Fish and shellfish are an important part of a healthy diet according to the EPA and nutrition experts Fish and shellfish contain high quality protein and other essential nutrients are low in saturated fat and contain omega 3 fatty acids Yet some fish and shellfish contain higher levels of mercury that may harm an unborn baby or young child s developing nervous system the EPA warns By following these three EPA recommendations for selecting and eating fish or shellfish women and young children will receive the benefits of eating these foods and also reduce their exposure to the harmful effects of mercury 1 Do not eat shark swordfish king mackerel or tilefish because they contain high levels of mercury These are larger fish that have lived longer than smaller fish and so have had more time to accumulate methylmercury in their bodies Safest are fish small enough to fit whole in a pan 2 Eat up to 12 ounces or two average meals a week of a variety of fish and shellfish that are lower in mercury Five of the most commonly eaten fish that are low in mercury are shrimp canned light tuna salmon pollock and catfish Another commonly eaten fish albacore tuna has more mercury than canned light tuna So when choosing two meals of fish and shellfish the EPA advises women and children to eat only one average meal of albacore tuna per week 3 Check local advisories about the safety of fish caught by family and friends in your local lakes rivers and coastal areas If no advice is available eat up to six ounces per week of fish you catch from local waters but don t consume any other fish during that week Regular consumption of types of fish that are high in methylmercury can result in mercury accumulation in the bloodstream over time Methylmercury is removed from the body naturally but it may take over a year for the levels to drop significantly says the EPA so mercury may be present in a woman s bloodstream before she becomes pregnant For this reason women who are trying to become pregnant should avoid eating fishes that are high in mercury For a national listing of fish advisories from the Environmental Protection Agency click here
View Full Document
Unlocking...