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National Water-Quality Assessment Program (NAWQA)
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States List:
New York
Ohio and Michigan
South Carolina

State of Mississippi - In 2000, the State of Mississippi convened a Fish Advisory Task Force to develop procedures regarding fish consumption advisories for organochlorine compounds and other contaminants. Recommendations by the Task Force to the Mississippi Departments of Environmental Quality and Health were based on USEPA risk-based assessment guidelines, rather than old FDA standards. Fish tissue data from the NAWQA Program in the Mississippi Embayment played an important role in this change of approach and new advisories because it demonstrated that elevated organochlorine levels have persisted in fish in this part of the country longer than anticipated by most managers. Concentrations of total DDT collected from 30 of the 41 sites sampled in the Mississippi Embayment exceeded guidelines established to protect wildlife. In fact, fish collected in 1995 showed that the highest concentrations of total DDT in fish tissue throughout the entire Mississippi River drainage were in the Mississippi Embayment study area. Streams demonstrating elevated levels in fish by USGS, such as some in the Delta region in Mississippi, are included in the preliminary state fish-consumption advisories, minimizing necessary sampling by the State and, therefore, resulting in cost-effective and timely management decisions.

State of New York - NAWQA findings documented the occurrence of PCBs in the Mohawk River in the vicinity of Utica and Little Falls, New York. These results contributed to decisions by the New York State Department of Health to issue fish consumption advisories on carp and selected game fishes, including largemouth bass and tiger muskellunge.

Lake Erie Drainage, Ohio and Michigan - NAWQA findings in the Lake Erie-Lake Saint Clair Drainages show that certain organochlorine contaminants were 10 to 100 times more concentrated in fish than in the streambed sediments of streams and major rivers. DDT, chlordane, dieldrin, PCBs, and the trace metal, mercury were the most frequently detected contaminants in fish in these drainages. Fish-consumption advisories are posted in the Lake Erie Drainage due to the prevalent contamination by mercury and PCBs.

State of Washington - NAWQA scientists, participating on a multi-agency team studying Lake Roosevelt, a popular fishing area in Washington State, collected several species of fish to evaluate mercury contamination. The results led to a site-specific health advisory for mercury by the Washington State Department of Health, cautioning people about the consumption of walleye and possible adverse health effects from mercury.

The Washington State Departments of Ecology and Health, along with the Spokane Regional Health District, issued fish-consumption advisories for rainbow trout and mountain whitefish caught in the Spokane River from Upriver Dam, Washington, to the Idaho state line because of elevated levels of PCBs and lead. The first advisory was issued for lead in August 2000 following the release of NAWQA information on lead and other heavy metals. A second advisory was released in early 2001 for PCBs following a joint study by the State and USGS that looked at PCB occurrence, as well as more detailed surveys on the extent to which heavy metals spread downstream from Idaho's historic mining activities.

In the Yakima River Basin, results of a NAWQA study revealed elevated concentrations of the insecticide DDT in water, streambed sediment, and fish tissue. These findings were a potential concern, especially to the health of local Native Americans who rely on fish as a major food source, and for fish-eating birds. The Washington State Department of Health issued a statement on the health effects that may result from consuming fish in the Yakima River Basin and conducted a study on DDT in breast milk.

State of Texas - High levels of PCBs detected in fish in the Donna Canal in south Texas in the early 1990s led to a ban on possession and consumption of fish. Subsequent extensive sampling studies by the State of Texas continued to reveal high levels in fish but no information on potential sources. The Texas Natural Resource Conservation Commission approached the NAWQA Program in 1998 and requested suspended-sediment chemistry and coring methods to locate the PCB source. USGS sampling narrowed the potential source to a 90-meter stretch along the approximately 4-mile long Donna Canal. The State turned the results over to their Superfund Program to begin the process of assessment and clean up.

For a period of four years following the discovery of high levels of PCBs in fish tissue in the Donna Canal by the USEPA, the Texas Natural Resource Conservation Commission, in cooperation with the Texas Department of Health and Texas Parks and Wildlife Department, conducted a series of investigations aimed at identifying the source of PCB contamination in the Donna Canal and associated reservoirs. Unfortunately, the subsequent (three) water, (two) fish and (three) bottom sediment sampling efforts brought us no closer to finding a source of the PCBs. Later (in 1998) after the first Superfund Site Discovery and Assessment investigation yielded equally empty results, we felt it was time to get help. Today, I am pleased to say that, not only have we been able to narrow the potential source of PCB contamination to an area of the canal approximately 90 meters long, the suspended sediment sampling results from [USGS] studies have enabled us to refocus our Superfund Site Discovery and Assessment investigation efforts and I am confident that this project will be in remediation mode by this Fall. Of course, the real benefactors of your work are the people of the Rio Grande Valley who will have one public health problem less to contend with (Roger Miranda, Texas Natural Resource Conservation Commission, March 2001).

State of Florida - The USGS assessment (Water Quality in Southern Florida, 1996-98) indicates that mercury has accumulated in game fish and other parts of the food web because human influences and natural conditions in the Everglades region enhance the methylation of mercury to its organic form, methylmercury. The enrichment of methylmercury enhances mercury uptake by fish and other biota. As a result, the Everglades ecosystem has one of the highest ratios of methylmercury to total mercury in bottom sediment in 21 NAWQA basins studied nationwide.

As the largest freshwater wetland in the continental US, and one identified as being critically endangered by farming, drought, development and drainage in its watershed, the Florida Everglades has the misfortune to exhibit some of the highest concentrations of mercury in its fish and wildlife…The contributions of the USGS NAWQA Project team have been of vital importance to the [South Florida Mercury Science] Program. The USGS has brought together scientists of many disciplines and enabled the South Florida Mercury Science Program to develop a deeper understanding of the scope, scale, status and trends of mercury problems in Florida. This has thereby greatly enhanced our ability to model and manage the factors that contribute to this problem (Dr. Thomas Atkeson, Florida Department of Environmental Protection, April 2001).

State of South Carolina - Concentrations of mercury in clams and fish liver tissue from the Edisto River were 24 and 8 times greater, respectively, than the South Carolina action level for issuance of a fish-consumption advisory. The South Carolina Department of Health and Environmental Control (2000) has issued fish-consumption advisories because of high levels of mercury in 49 rivers and reservoirs in the Santee River Basin, including the Edisto River.

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