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Mercury in fish causes concern By Mark Freeman Unhealthy levels of mercury found in fish caught last spring in Galesville and Cooper Creek reservoirs in Douglas County have Oregon health officials warning against eating any fish caught there. The Oregon Health Division issued its advisories this week for people who regularly or frequently eat fish caught in Galesville, a popular largemouth bass-fishing lake near Azalea, and in Cooper Creek, which sports a popular spring bass and crappie fishery just outside Sutherlin. The agency recommends that anglers instead release all the fish they catch there, but it also sets some guidelines for people who still wish to eat some of the fish they catch. Levels of mercury found in the tissues of Galesville fish were twice the threshold that health division officials consider as worthy of a public warning. In Cooper Creek, the mercury levels were slightly less but some fish caught there showed levels of more than three times the warning thresholds. When ingested, the element can cause brain and nerve damage to growing fetuses, infants and small children as well as attacking the nervous system, livers and kidneys of adults. Children, pregnant and nursing women, and women of child-bearing age are most susceptible to the effects of mercury. The mercury is considered to originate from natural sources within the rocks and soil of the reservoir�s watersheds and has accumulated in the fish over time through the food chains, according to Ken Kauffman, a state environmental health specialist who conducted the health analyses that led to the warnings. "There�s always mercury in fish, no matter where you get them," Kauffman said. "It�s a matter of how much." For the largemouth bass in Galesville, as well as the largemouth and the black crappie in Cooper Creek, how much is considered too much, Kauffman said. Most healthy adults can safely eat as much as one 8-ounce piece of fish from either reservoir each week. Most children, however, should limit their eating of Galesville and Cooper Creek fish to no more than a 4-ounce serving every seven weeks, while most women should not eat more than one 8-ounce serving a month. The two reservoirs are part of 14 Oregon water bodies where health advisories are listed, according to Kauffman. But such tests have been done on only about 100 of Oregon�s 35,000 identified water bodies, he said. In Jackson County, fish caught from Applegate Lake have been tested and shown to contain mercury, but not at levels warranting a health advisory, Kauffman said. No tests have been conducted for mercury at Lost Creek, Willow, Agate, Emigrant, Hyatt and Howard Prairie lakes, he said. The lack of testing, Kauffman added, is because of a lack of state funding. Mercury is a worldwide health issue and so prevalent in the aquatic food chain that is present in virtually all fish, including those caught in the ocean. Because the element builds up over time, older and larger fish tend to have higher concentrations of mercury. Since mercury chemically bonds with muscle tissue, it cannot be removed or significantly reduced by fish-cleaning methods, cooking, brining and even smoking them. The mercury levels in both reservoirs do not pose hazards for swimming or other activities. Largemouth bass in Galesville had, on average, .69 parts per million of mercury and some of the tested fish had levels as high as .86 ppm, Kauffman said. At Cooper Creek, the average mercury level was .63 ppm, and the worst fish tested contained 1.12 ppm, he said. Health officials generally issues warnings when fish levels average .35 ppm or greater. Sport-fishing rules allow anglers to keep one Galesville bass over 15 inches a day to eat. Cooper Creek has the standard bass limit of up to five per day, but no more than three over 15 inches long. There are no limits on crappie in Cooper Creek. The naturally present mercury likely leaches and erodes slowly from soil and rocks, accumulating in underwater sediment and eventually entering the food chain at its lowest levels and accumulating in fish. The levels are not expected to diminish or disappear in the foreseeable future, state health division spokeswoman Bonnie Widerburg said. If future tests show significant changes in mercury levels, the advisories will be amended, she said. Staff writer Mark Freeman covers the outdoors for the Mail Tribune. Call him at 776-4470, or e-mail him at [email protected] ) Mail Tribune Home | Ottaway Newspapers, Inc. | Dow Jones & Co., Inc. | Privacy | Contact Us Copyright � 2001 Mail Tribune, Inc.