Ambient toxicity testing in the Chesapeake Bay watershed using freshwater and estuarine water column tests
ABSTRACT This study was designed to identify toxic ambient areas in the Chesapeake Bay watershed by using the following three estuarine and two freshwater 8-d water column toxicity tests: sheeps-head minnow, Cyprinodon variegatus, larval survival and growth test; grass shrimp, Palaemonetes pugio, larval survival and growth test; copepod, Eurytemora affinis, life cycle test; fathead minnow, Pimephales promelas, larval survival and growth test; and Ceriodaphnia dubia, survival and reproduction test. Ambient water was collected from the following locations and transported back to our laboratory for testing: Elizabeth River (VA), Patapsco River (MD), Wye River (MD), and Potomac River (three freshwater and two saltwater stations). The Potomac River stations were located at Indian Head (MD), Freestone Point (VA), Possum Point (VA), Morgantown (MD), and Dahlgren (VA). A suite of inorganic and organic contaminants and water quality conditions were evaluated in ambient water during the tests. Results from the water column tests demonstrated no significant ranking of sensitivity among the three saltwater tests, but rather supported the need for multispecies tests because different species displayed varying sensitivity to different types of contaminants. Biological effects were reported from at least one test species tested in ambient water from Elizabeth River, Patapsco River, Indian Head, Morgantown, and Dahlgren. These results demonstrate that selected ambient areas of the Chesapeake Bay watershed are toxic, based on various biological indicators.
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ABSTRACT: The objectives of this study were to identify toxic ambient areas in the Chesapeake Bay watershed by using a battery of water column and sediment toxicity tests. Twenty-five ambient stations in nine river/harbors were tested during 1990 through 1994. Seasonal and annual comparisons were conducted at selected stations. Inorganic and organic contaminants were evaluated in ambient water and sediment concurrently with water column and sediment tests to assess possible causes of toxicity, although absolute causality cannot be established. Multivariate statistical analysis was used to develop a TOX-INDEX at each station for both water column and sediment toxicity data. Water column tests from the 5-year testing period showed that 43% of the time, some degree of toxicity was reported. The most toxic sites based on water column results were located in urbanized areas such as the Elizabeth River, Baltimore Harbor, and the Middle River. Water quality criteria for copper, lead, mercury, nickel, and zinc were exceeded at one or more of these sites. Some degree of sediment toxicity was reported from 70% of the tests conducted during the 5-year period. The Elizabeth River and Baltimore Harbor stations were reported as the most toxic areas based on sediment results. Sediment toxicity guidelines (Long and Morgan effects range median [ER-M] values) were exceeded for one or more of the following metals at these two locations: arsenic, cadmium, chromium, copper, lead, nickel, and zinc. At the Elizabeth River stations 9 of 16 semivolatile organics and 2 of 7 pesticides measured exceeded the ER-M values. Various semivolatile organics exceeded the ER-M values at a number of Baltimore Harbor sites; pyrene and dibenzo (a,h) anthracene were particularly high at one of the stations (Northwest Harbor).Environmental Toxicology and Chemistry 07/1997; 16(8):1606 - 1617. · 2.62 Impact Factor
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ABSTRACT: Various estuarine water column toxicity tests were conducted twice in nine different ambient stations in the Chesapeake Bay watershed over a 2-year period (1991 to 1993) to determine if toxic conditions existed. The following 8-d toxicity tests were conducted: larval sheepshead minnow (Cyprinodon variegatus) survival and growth test; larval grass shrimp (Palaemonetes pugio) survival and growth test; and a copepod (Eurytemora affinis) life-cycle test. During the second year of testing, two 48-h coot clam (Mulinia lateralis) tests were conducted at each station during each testing period. In 1991, the toxicity tests were conducted twice at stations in the Potomac River at Morgantown and Dahlgren, and in the Patapsco River and the Wye River at the Manor House. All of the above tests were conducted during the fall of 1992 and spring of 1993 at two stations in the Wye River, Nanticoke River, and Middle River. Inorganic contaminants, organic contaminants, and water-quality conditions were measured concurrently during the toxicity testing of ambient water. In 1991, reduced growth of sheepshead minnow larvae was reported at both Potomac River stations during the first test. Significant mortality of either the copepod or sheepshead minnow larvae was also reported at the Wye River during both tests. Results from the 1992/93 testing generally showed minimal effects for three of the test species at all stations. Reduced normal shell development was reported for the coot clam at both Middle River stations during the fall and spring tests concurrently with concentrations of various trace metals that exceeded chronic marine water-quality criteria.Environmental Toxicology and Chemistry 10/2009; 14(2):267 - 278. · 2.62 Impact Factor