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S. Goodbred

Publications and source records attributed to S. Goodbred.

3 recordsLinked to original sources

Sperm quality biomarkers complement reproductive and endocrine parameters in investigating environmental contaminants in common carp (Cyprinus carpio) from the Lake Mead National Recreation Area

Lake Mead National Recreational Area (LMNRA) serves as critical habitat for several federally listed species and supplies water for municipal, domestic, and agricultural use in the Southwestern U.S. Contaminant sources and concentrations vary among the sub-basins within LMNRA. To investigate whether exposure to environmental contaminants is associated with alterations in male common carp ( Cyprinus carpio ) gamete quality and endocrine- and reproductive parameters, data were collected among sub-basins over 7 years (1999–2006). Endpoints included sperm quality parameters of motility , viability, mitochondrial membrane potential, count, morphology, and DNA fragmentation; plasma components were vitellogenin (VTG), 17ß-estradiol, 11-keto-testosterone, triiodothyronine, and thyroxine. Fish condition factor, gonadosomatic index, and gonadal histology parameters were also measured. Diminished biomarker effects were noted in 2006, and sub-basin differences were indicated by the irregular occurrences of contaminants and by several associations between chemicals (e.g., polychlorinated biphenyls, hexachlorobenzene , galaxolide, and methyl triclosan) and biomarkers (e.g., plasma thyroxine, sperm motility and DNA fragmentation). By 2006, sex steroid hormone and VTG levels decreased with subsequent reduced endocrine disrupting effects. The sperm quality bioassays developed and applied with carp complemented endocrine and reproductive data, and can be adapted for use with other species.

Lake Mead National Recreation Area↗

The response of hydrophobic organics and potential toxicity in streams to urbanization of watersheds in six metropolitan areas of the United States

Semipermeable membrane devices (SPMDs) were deployed in streams along a gradient of urban land-use intensity in and around six metropolitan areas: Atlanta, Georgia; Raleigh–Durham, North Carolina; and Denver–Fort Collins, Colorado, in 2003; and Dallas–Fort Worth, Texas; Milwaukee–Green Bay, Wisconsin; and Portland, Oregon, in 2004 to examine relations between percent urban land cover in watersheds and the occurrence, concentrations, and potential toxicity of hydrophobic compounds. Of the 142 endpoints measured in SPMD dialysates, 30 were significantly (alpha = 0.05) related to the percent of urban land cover in the watersheds in at least one metropolitan area. These 30 endpoints included the aggregated measures of the total number of compounds detected and relative toxicity (Microtox® and P450RGS assays), in addition to the concentrations of 27 individual hydrophobic compounds. The number of compounds detected, P450RGS assay values, and the concentrations of pyrogenic polycyclic aromatic hydrocarbons (PAHs) were significantly related to percent urban land cover in all six metropolitan areas. Pentachloroanisole, the most frequently detected compound, was significantly related to urban land cover in all metropolitan areas except Dallas–Fort Worth. Petrogenic PAHs and dibenzofurans were positively related to percent urban land cover in Atlanta, Raleigh–Durham, Denver, and Milwaukee–Green Bay. Results for other endpoints were much more variable. The number of endpoints significantly related to urban land cover ranged from 6 in Portland to 21 Raleigh–Durham. Based on differences in the number and suite of endpoints related to urban intensity, these results provide evidence of differences in factors governing source strength, transport, and/or fate of hydrophobic compounds in the six metropolitan areas studied. The most consistent and significant results were that bioavailable, aryl hydrocarbon receptor agonists increase in streams as basins become urbanized. Potential toxicity mediated by this metabolic pathway is indicated as an important factor in the response of aquatic biota to urbanization.

Georgia, North Carolina, Colorado, Texas, Wisconsi↗

Pesticide and PCB residues for loggerhead shrikes in the Shenandoah Valley

The decline in loggerhead shrike ( Lanius ludovicianus ) populations is widespread and coincides with the use of organochlorines that began in the late 1940's and increased until the 1970's (Morrison 1981; Robbins et al. 1986; Tate 1986). An inhabitant of farmland areas, loggerhead shrikes prey on invertebrates and small vertebrates (Bent 1950), and thus risk exposure to pesticides and other agricultural chemicals. The role of contaminants in the decline of loggerhead shrikes has only been partially assessed (Busbee 1977; Anderson and Duzan 1978; Morrison 1979; Rudd et al. 1981). Studies of the nesting and winter ecology of loggerhead shrikes (Luukkonen 1987; Blumton 1989) during 1985-88 in the Shenandoah Valley, Virginia provided the opportunity to collect eggs and carcasses for contaminant residue analysis. In this paper we provide pesticide and polychlorinated biphenyl (PCB) residue data for eggs and carcasses collected.

Shenandoah Valley↗