Abstract-To assess the effects of polychlorinated biphenyls (PCBs) on reproduction, female Fundulus heteroclitus were exposed to a mixture of non-ortho-and mono-ortho-PCBs, mimicking the mixture found in fish collected from New Bedford Harbor, Massachusetts, USA, a PCB-contaminated estuary. Exposure was by intraperitoneal injection of the mixture dissolved in corn oil. Doses of 0.76, 3.8, and 19 g PCB mixture per gram of wet weight produced liver concentrations of 2.99, 12.2, and 32.8 g nonortho-and mono-ortho-PCBs per gram of dry liver, with dioxin toxic equivalency concentrations (TEQs) of 0.063, 0.409, and 0.720 ng/g, respectively. Female mortality was 58%, and egg production was reduced by 77% at the highest dose, compared to controls. Food consumption declined with increasing PCB concentration, suggesting that PCBs act indirectly to reduce fecundity through an energetic effect. Pituitary gonadotropin content appeared to be suppressed at the highest dose, but the ability of ovarian follicles to produce estradiol and testosterone in vitro was not impaired. Significant residue-effects linkages were found, with TEQ emerging as a potential indicator of adverse effects. Mortality was directly related, and egg production was inversely related to log 10 TEQ. Multiple regression analysis indicated that egg production was directly related to pituitary gonadotropin content and food consumption.

New Bedford Harbor (NBH), MA, is a Superfund site because of high polychlorinated biphenyl (PCB) concentrations in the sediment. From April 1994 to September 1995, a remedial dredging operation (termed the "Hot Spot") removed the most contaminated sediments (PCB concentrations greater than 4000 microg/g) from the upper harbor. During remediation, a monitoring program assessed the potential environmental impacts to NBH and adjacent Buzzards Bay. The monitoring program was developed with input from federal, state, and local authorities. Site-specific decision criteria were established to assess net PCB transport, water column toxicity, and PCB bioaccumulation in blue and ribbed mussels (Mytilus edulis and Geukensia demissa, respectively). The remediation was completed without exceeding PCB net transport or acute toxicity effects specified in the decision criteria. In addition, PCB bioaccumulation in mussels during this time period was not significantly greater than pre- or post-operational measurements. The results indicated that approximately 14000 cubic yards of highly PCB contaminated sediment were permanently removed with minimal environmental effects. The lessons learned during this operation, as well as previous pilot studies at the site, will be used to make full-scale remedial efforts in NBH more efficient and environmentally protective.

New Bedford Harbor (NBH), located in southeastern Massachusetts, was designated as a marine Superfund site in 1983 due to sediment contamination by polychlorinated biphenyls (PCBs). Based on risks to human health and the environment, the first two phases of the site cleanup involved dredging PCB-contaminated sediments from the harbor. Therefore, a long-term monitoring program (LTM) was developed to measure spatial and temporal chemical and biological changes in sediment, water, and biota to assess the effects and effectiveness of the remedial activities. A systematic, probabilistic sampling design was used to select sediment sampling stations. This unbiased design allowed the three segments of the harbor to be compared spatially and temporally to quantify changes resulting from dredging the contaminated sediments. Sediment was collected at each station, and chemical (e.g., PCBs and metals), physical (e.g., grain size), and biological (e.g., benthic community) measurements were conducted on all samples. This paper describes the overall NBH-LTM approach and the results from the five rounds of sample collections. There is a decreasing spatial gradient in sediment PCB concentrations from the northern boundary (upper harbor) to the southern boundary (outer harbor) of the site. Along this same transect, there is an increase in biological condition (e.g., benthic community diversity). Temporally, the contaminant and biological gradients have been maintained since the 1993 baseline collection; however, since the onset of full-scale remediation, PCB concentrations have decreased throughout the site, and one of the benthic community indices has shown significant improvement in the lower and outer harbor areas.

Blue mussels (Mytilus edulis) were deployed to monitor the levels of bioavailable contaminants during a pilot dredging project in New Bedford Harbor (NBH), Massachusetts. Dissolved and particulate seawater samples also were collected periodically during these deployments. Poly‐chlorinated biphenyl (PCB) congener concentrations in both mussel tissue and seawater samples were among the quantified contaminants. Large differences in the dissolved and particulate PCB concentrations in seawater and tissue residue concentrations in mussels were observed along a gradient from the upper harbor to Buzzards Bay. Bioconcentration factors (BCFs) were calculated for six PCB congeners at two stations in NBH and a reference site in Buzzards Bay. Equations were generated relating the log BCF to the log octanol/water partition coefficient (Kow) for these congeners. A consistent relationship was found between dissolved PCB congener concentrations and tissue concentrations in the mussels. This study demonstrates the utility of the blue mussel as a monitoring organism for quantifying bioavailable contaminants in seawater and for relating PCB tissue residues with seawater concentrations.