Organochlorine chemical residues and elemental concentrations were measured in piscivorous and benthivorous fish at 111 sites from large U.S. river basins. Potential contaminant sources such as urban and agricultural runoff, industrial discharges, mine drainage, and irrigation varied among the sampling sites. Our objectives were to provide summary statistics for chemical contaminants and to det...

Estrogenic pesticides such as DDT and chlordecone generate deleterious reproductive effects. An "in culture" bioassay was used to assess the estrogenicity of several pesticides. The E-screen test uses human breast estrogen-sensitive MCF7 cells and compares the cell yield achieved after 6 days of culture in medium supplemented with 5% charcoal-dextran stripped human serum in the presence (positi...

Organochlorine pesticide and total polychlorinated biphenyl (PCB) concentrations were measured in largemouth bass from the Tombigbee River near a former DDT manufacturing facility at McIntosh, Alabama. Evaluation of mean p,p'- and o,p'-DDT isomer concentrations and o,p'- versus p,p'-isomer proportions in McIntosh bass indicated that DDT is moving off site from the facility and into the Tombigbe...

Rats were given a single dose of toxaphene (120 mg/kg, equivalent to 1/2 LD50) and sacrificed at 1, 5, and 15 days. Liver weight and hepatic microsomal enzyme activity were increased at day 5 and 15. The level of plasma testosterone was significantly decreased at day 15. In a second experiment rats were given 2.4 mg/kg daily and sacrificed at 1, 3 and 6 months. Liver weight and microsomal enzym...

Xenobiotics suspected of being estrogenic-the PCB aroclor 1242 and the pesticides toxaphene, dieldrin, p,p'-DDD, cis-Nonachlor, trans-Nonachlor, p,p'-DDE, and chlordane-were examined for their ability to override a male-producing incubation temperature and result in female hatchlings in the red-eared slider, a turtle with temperature-dependent sex determination. Compounds were assayed in the en...

Residues of two organochlorines (OCs) -Aroclor 1268 (a highly chlorinated PCB formulation) and toxaphene (a DDT-replacement pesticide) -are major persistent contaminants in St. Simons Sound near Brunswick, Georgia, USA. Although studies have recently documented OC levels in Brunswick area fish that are routinely consumed by humans, little is known about organochlorine body burdens in resident m...