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J E Weinstein

Publications and source records attributed to J E Weinstein.

7 recordsLinked to original sources
PubMed2006

Dietary transfer of fluoranthene from an estuarine oligochaete (Monopylephorus rubroniveus) to grass shrimp (Palaemonetes pugio): Influence of piperonyl butoxide.

The objective of this study was to determine the potential for dietary transfer of sediment-associated fluoranthene from tubificid oligochaetes (Monopylephorus rubroniveus) to grass shrimp (Palaemonetes pugio). Grass shrimp, either in the presence or absence of sublethal waterborne concentrations of the metabolic inhibitor, piperonyl butoxide (PBO), were fed fluoranthene-dosed oligochaetes for 5-days. All grass shrimp bioaccumulated fluoranthene; however, bioaccumulation was 3X higher in the presence of PBO. Trophic transfer coefficients (TTCs) were 0.02 and 0.01 in the presence and absence of PBO, respectively. Following the 5-day accumulation period, shrimp in both treatments were allowed to depurate for 3 days. Depuration rates were significantly higher in PBO-exposed shrimp. These results demonstrated that sediment-associated fluoranthene can be transferred through the diet from oligochaetes to grass shrimp, and the presence of PBO enhanced fluoranthene bioaccumulation. However, the comparatively low TTCs suggest that biomagnification of fluoranthene in estuarine food webs is low.

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PubMed2001

Characterization of the acute toxicity of photoactivated fluoranthene to glochidia of the freshwater mussel, Utterbackia imbecillis.

The acute photoactivated toxicity of fluoranthene to the glochidial larvae of the paper pondshell, Utterbackia imbecillis, was characterized in the laboratory using three sets of experiments. Toxicokinetic studies revealed that glochidia rapidly bioaccumulated fluoranthene, reaching an apparent steady state in 4 h. Based on a two-compartment model, uptake (Ku) and depuration (Kd) rate constants were 1394 ml/g/h and 0.769/h, respectively. However, experimental data suggested the presence of a fast and slow depuration compartment with a Kd of 0.290 and 0.031/h, respectively. Replicate 24-h acute toxicity tests designed to determine the overall sensitivity of glochidia to photoactivated fluoranthene were conducted under simulated sunlight (ultraviolet [UV]-A = 69.0 +/- 1.0 microW/cm2) (mean +/- standard deviation [SD]). Mean median lethal concentrations (LC50) of fluoranthene at 8, 16, and 24 h were 5.59 +/- 0.59, 4.09 +/- 0.57, and 2.45 +/- 0.45 micrograms/L, respectively. Mean median lethal doses (LD50) at the same time periods were 14.76 +/- 2.17, 11.66 +/- 2.82, and 6.98 +/- 1.31 micrograms/g dry weight, respectively. Acute toxicity tests designed to elucidate the relationship between the rate of mortality and UV intensity were conducted under one of four different UV intensities (UV-A = 15, 31, 50, and 68 microW/cm2). Regression analysis revealed that the time-dependent mortality of glochidia was inversely related to the product of initial tissue residue of fluoranthene and UV intensity. These findings suggest that glochidia of freshwater mussels are among the most sensitive organisms tested to date to photoactivated fluoranthene and the time-dependent mortality of glochidia can accurately be predicted through evaluation of the product of fluoranthene tissue residue and the light intensity to which the glochidia is exposed.

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PubMed2001

Phototoxicity of anthracene and pyrene to glochidia of the freshwater mussel Utterbackia imbecillis.

The acute toxicity of photoactivated anthracene and pyrene to the glochidial larvae of the paper pondshell (Utterbackia imbecillis) was characterized in the laboratory using two sets of experiments. Acute toxicity tests designed to determine the overall sensitivity of glochidia to anthracene and pyrene were conducted under simulated sunlight (ultraviolet [UV]-A = 70+/-0.5 microW/cm2 [mean +/- standard deviation]). The median lethal concentration (LC50) and median lethal dose (LD50) of anthracene at 24 h were 1.93 (95% CI, 0.87-3.02) microg/L and 1.94 (1.87-2.00) microg/g glochidia, respectively. The LC50 and LD50 for pyrene at 24 h were 2.63 (2.38-2.90) microg/L and 6.36 (5.82-6.94) microg/g glochidia, respectively. Acute toxicity tests designed to delineate the relationship between the rate of mortality and UV intensity were conducted under one of four different UV intensities (UV-A = 15, 31, 50, and 68 microW/cm2). Regression analyses revealed that time to death decreased as tissue residue concentrations and UV intensity increased for both compounds. Based on measured tissue residues, anthracene was 1.5-fold more potent than pyrene and 3-fold more potent than fluoranthene. The lower potency of fluoranthene is in agreement with previously developed structure-activity relationships; however, these relationships predict equal potency between anthracene and pyrene. These findings suggest that glochidia of freshwater mussels are sensitive to photoactivated anthracene and pyrene at environmentally relevant concentrations, that the time-dependent mortality of glochidia can be accurately predicted through evaluating the product of tissue residue and light intensity, and that species-dependent factors may alter the predicted relative potencies of anthracene and pyrene.

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PubMed1995

Seasonal responses of the mixed-function oxygenase system in the American oyster, Crassostrea virginica (Gmelin 1791), to urban-derived polycyclic aromatic hydrocarbons.

Mixed-function oxygenase (MFO) system components (cytochrome P450 and b5, "423 peak" and NADPH cytochrome c reductase) and body burdens of polycyclic aromatic hydrocarbons (PAHs) were determined seasonally in oysters, Crassostrea virginica (Gmelin 1791), collected from an undeveloped estuary (North Inlet, SC) and an urbanized estuary (Murrells Inlet, SC). All MFO system components monitored in oysters from North Inlet demonstrated seasonal variations; levels were lowest during October 1992. Whole oyster PAH tissue levels were always higher in Murrells Inlet oysters compared with North Inlet oysters. Seasonal variation of PAH body burdens was evident in oysters from Murrells Inlet; the highest levels occurred during April 1993. Differences between the two estuaries were seasonally evident in most oyster MFO system components. Reductase activity was highest at the most contaminated Murrells Inlet site during October 1992 and April 1993. This seasonal variation was positively correlated to that of their PAH body burdens. Cytochrome P450 content was also elevated at the most contaminated site during April 1993. These results suggest that reductase activity and cytochrome P450 content in Murrells Inlet oysters were induced by the high PAH body burdens during April 1993 and indicate their potential as molecular biomarkers of PAH contamination.

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PubMed1992

Shell disease and metal content of blue crabs, Callinectes sapidus, from the Albemarle-Pamlico Estuarine System, North Carolina.

Concentrations of 13 elements were determined for three tissues (gill, hepatopancreas, muscle) in diseased crabs from a contaminated estuary (Pamlico River, NC), and in non-diseased crabs from both the contaminated estuary and a relatively uncontaminated area (Albemarle Sound, NC) during the fall 1989 and summer 1990. The diseased crabs had lesions which completely penetrated their dorsal integument, while the non-diseased crabs lacked lesions. Sediments within the contaminated area showed enrichment of arsenic, cadmium, manganese, titanium and vanadium relative to the uncontaminated area. Levels of aluminum, arsenic, cobalt, manganese, nickel, titanium, vanadium and zinc were significantly higher in both gill and hepatopancreas in crabs from the contaminated area. Manganese was always highest in the diseased crabs in all tissues measured. The concentrations of the remaining elements were greater in the gills of diseased crabs, while highest values of these elements in the hepatopancreas varied among the diseased and non-diseased crabs from the polluted area. Conversely, copper levels were always highest in all tissues in crabs from the uncontaminated area, and typically lowest in the diseased crabs. Concentrations of aluminum and arsenic were also significantly greater in the muscle tissue of crabs from the contaminated area, but no distinct trend was evident with regard to diseased versus non-diseased crabs. Arsenic was the only element accumulated by crabs in the contaminated area which has a known toxic affect on the tissue responsible for cuticle synthesis and repair (hypodermis) in crustaceans. Metals also accumulated could possibly act synergetically to compromise normal metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)

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