Sunday, April 17, 2011

Revised Maryland Fish Advisories: You Can Eat More Striped Bass

     Baltimore, MD -- Revised fish consumption advisories from the Maryland Department of the Environment show that a healthy diet can include more striped bass than previously recommended. MDE’s revised advisories increase the recommended meal limits for striped bass for nearly every population group for fish caught in the Chesapeake Bay or in Maryland’s Atlantic coastal waters. The new recommendations stem from recent test results that showed a significant decline in levels of contaminants in striped bass from Maryland waters. Also, MDE data suggest that contaminant levels are even lower in striped bass fillets prepared, as the Department has long recommended, without fatty portions of the fish.
     “Anyone who enjoys eating Maryland striped bass will welcome this news,” said Governor Martin O’Malley. “This is good news for anglers who catch fish to feed themselves and their families and for businesses that benefit from recreational fishing. It’s also heartening for everyone working to restore the Chesapeake Bay.”
     “Maryland's fish consumption advisories help us make the best choices about what fish we eat and how often we eat them as part of a healthy diet," said MDE Acting Secretary Robert M. Summers. "Contamination has decreased in the striped bass we tested, and although we do not have the data to identify a specific explanation for the decline, PCBs have been banned in the United States since 1979, and we're encouraged by this positive indication of the improving quality of our waters."
     The striped bass, also known as rockfish, is the iconic species of Maryland sport fishing. Its population, once so threatened that a moratorium was placed on its harvesting, has rebounded in recent years.
     The revised advisories being announced also include recommendations on the consumption of bluefish caught in Maryland’s Chesapeake Bay and Atlantic Coast.

The advisories: old versus new     Under the new advisories, the recommended meal limits for the general population for smaller striped bass caught in the Chesapeake Bay increased by 50 percent, from two per month to three per month. Also, the advisories no longer include the “avoid” recommendation that had existed for women and children for certain striped bass.
     The differences between the old and new advisories reflect a significant decline in the level of polychlorinated biphenyls (PCBs) in striped bass analyzed by MDE. Median PCB levels fell by more than half between fish analyzed from 2001 to 2005 and fish analyzed in 2009 and 2010 (see Table 2). MDE does not have the information needed to draw specific conclusions about the factors that led to these results, but the Department is encouraged by this data and will continue to track contaminant levels in striped bass and other fish.

Fillet preparation affects PCB levels     When filleting, MDE recommends removing fatty portions where PCBs tend to concentrate, including the belly flap and the dark meat along the side of the fillet. To evaluate this recommendation in striped bass, MDE compared PCB levels in non-fatty dorsal fillet samples to whole fillet samples. PCB levels were reduced by 75 to 91 percent in the dorsal samples, with the general trend being a greater reduction with increasing size of fish. These results support the value of the filleting recommendations and give Marylanders a good reason to consider how they prepare striped bass fillets, in addition to following the meal limits in the striped bass advisory.

New bluefish advisories      MDE is also releasing an advisory for bluefish caught in Maryland’s Chesapeake Bay and Atlantic coastal waters. MDE has been able to obtain PCB data on bluefish smaller than 15 inches and greater than 28 inches but not on fish between 15 and 28 inches. Based on the available data for bluefish, MDE recommends a limit of two meals per month for bluefish less than 15 inches in length, but to avoid consumption of bluefish 15 inches and longer. These advisories could change as MDE learns more about the medium-size bluefish.

General information about MDE’s fish consumption advisories     Fish can be an important part of a healthy diet. They are a good source of high-quality protein and nutrients and are low in saturated fat. They are high in helpful omega fatty acids. A well-balanced diet that includes a variety of fish can contribute to a child’s proper growth and development. The American Heart Association recommends that adults eat fish at least twice a week for a healthier heart.
     MDE’s fish consumption advisories provide recommended limits on how often certain fish can be eaten and still enjoy the health benefits while minimizing health risks. They are intended for people who eat Maryland fish on a regular basis, including people who fish in local waters to provide food for themselves and their families and people who eat Maryland fish caught by sport fishermen.
     To develop the advisories, MDE analyzes fish tissue for two contaminants which can pose health risks and which are known to accumulate in fish: PCBs and methylmercury.
     PCBs, which have been banned in the United States since 1979, are synthetic oils that were primarily used as insulating fluids in heavy-duty electrical equipment. They enter the environment in multiple ways, including releases through faulty and broken equipment and unauthorized dumping. PCBs are very stable; once they are in the environment, they take a long time to break down and are still present in our environment today. The manufacture of PCBs was banned because of accumulation in the environment and risks to human health. They are taken up into the bodies of small organisms and fish. As a result, people who eat the fish may be exposed to PCBs that have accumulated in the fish.
     Methylmercury is a form of mercury, a metal that occurs naturally but is also released into the environment by some industrial processes and the burning of coal and municipal solid waste. Mercury is converted to methylmercury by bacteria in water and soil. Fish absorb methylmercury as they feed. It builds up more in some types of fish than others.
     Both contaminants are thought to pose risks to developing brains, and PCBs are suspected to cause cancer in humans. The PCB and methylmercury data from fish sample testing are used in mathematical equations that factor in health risks to calculate the recommended number of meals. Updated statistical assumptions and new test results, as they become available, are being used in calculations to determine revised advisories. MDE expects to issue revised consumption advisories for other species and waterbodies in the near future.
     The advisories include separate categories for women and children because pregnant women, babies, and young children are particularly vulnerable to the effects of methylmercury and PCBs because of the potential harmful effect on developing brains.
     The advisories for a species can also differ for the size of the fish. Larger fish tend to accumulate higher levels of contaminants than smaller fish.
     MDE publicizes fish consumption advisories in a number of ways, including information on the Department’s website, postings at fishing locations as practical, and through outreach to target audiences such as anglers, through the guidebook typically distributed with fishing licenses, and to pregnant women and to children, through WIC centers.
     To view this press release and related charts visit http://www.mde.state.md.us/programs/PressRoom/Pages/041311.aspx

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