bluuebunny/crossref_metadata_2025_split huggingface dataset:
Treated wastewater as a source of sediment contamination in gulf of Mexico near-coastal areas: A survey
Authors: Lewis Michael , Weber David , Stanley Roman , Albrecht Barbara 
Published: March 2010

Abstract
The primary objective of this baseline survey was to provide some needed perspective on the magnitude of sediment contamination associated with wastewater outfalls discharged to Gulf of Mexico near-coastal areas. The chemical quality and toxicities of whole sediments and pore waters collected from three coastal rivers and four coastal bays receiving wastewaters were assessed during a 2-year period. Rooted plants, invertebrates, and fish were used to assess the acute and chronic toxicities of sediments associated with a total of 10 industrial, municipal, steam electric-power generation and forest product wastewater outfalls. Effects on bacterial bioluminescence, early seedling biomass, survival, reproduction, fertility, and growth were determined in bioassays ranging from 30 min to 28 d duration. Sediment chemical contamination was localized and decreased with increasing distance from the discharge areas. The major sediment contaminants, with few exceptions, were divalent trace metals, which increased, on average, by 69% below 8 of the 10 outfalls. However, only a few concentrations exceeded proposed threshold sediment quality assessment guidelines. Toxicity to either the plant or animal test species was observed occasionally below 7 of the 10 outfalls, but its detection was dependent on the type of bioassay and the frequency of use. Consequently, a suite of bioassays conducted on multiple occasions appears to be needed for toxicity assessments of sediments collected below wastewater discharges in the Gulf region to ensure relevancy of the results. This is particularly true for low to moderately contaminated sediments where acute toxicity is uncommon, which was the case in this study.
Environmental fate of nonylphenol ethoxylates: Differential adsorption of homologs to components of river sediment
Authors: John Dominic M , House W Alan , White Graham F 
Published: March 2010

Abstract
Nonylphenol ethoxylate (NPEOx) homologs present in commercial mixtures were rapidly adsorbed to and desorbed from native river sediment. Adsorption isotherms, established using high-performance liquid chromatography analysis to monitor individual homologs NPEO3 to NPEO13 simultaneously, were linear for each component adsorbing to native sediment, organic-free sediment, and kaolinite, usually with small positive intercepts on the isotherms indicating an additional low-capacity, high-affinity binding site. The adsorption partition coefficients (Kd) for the native sediment decreased progressively from 1,460 L/kg for NPEO3 to 450 L/kg for NPEO10, then increased again slightly for higher homologs. In contrast, Kd values for organic-free sediment (range 230–590 L/kg) or kaolinite (190–490 L/kg) increased steadily from NPEO3 to NPEO13. Adsorptions to silica and alumina were very weak, but to sewage sludge all components adsorbed strongly (Kd values 12,000–33,000, with a maximum at NPEO7). The adsorption to sewage sludge was related to the low-capacity, high-affinity sites observed for native sediment. Dependence of Kd values on ethoxylate chain length was analyzed, in terms of both possible adsorption mechanisms, and the environmental fate and impact of NPEOxs as endocrine disruptors.
Estrogenicity of benzophenones evaluated with a recombinant yeast assay: Comparison of experimental and rules-based predicted activity
Authors: Schultz T Wayne , Seward Julie R , Sinks Glendon D 
Published: March 2010

Abstract
In a previous study, structure-based rules were formulated to predict estrogenicity of phenolic molecules. The determination of estrogenic activity (EC50) and acute toxicity (LC50) of benzophenones was undertaken, and experimental and predicted estrogenic potency values were compared. The Saccharomyces cerevisiae-based lac-Z reporter assay was used to generate experimental data. Estrogenicity was measured colormetrically as β-galactosidase activity. On the basis of the series of rules, β-galac-tosidase activity was predicted correctly for 14 of the 18 benzophenones tested. As predicted, benzophenone, as well as derivatives with a methyl-, chloro-, or nitro-substituent, exhibited no β-galactosidase activity. As anticipated, 4-hydroxybenzophenone exhibited weak β-galactosidase activity (EC50 value of e-06 M). The 3-hydroxybenzophenone exhibited almost the same activity as the 4-hydroxy derivative, whereas the 2-hydroxy derivative was nonactive. It was observed while replacing the para-hydroxyl group with an amino moiety decreased β-galactosidase activity by a half order of magnitude, replacement of the para-hydroxy moiety with a methoxy group negated activity. The nonsymmetrical trihydroxylated benzophenone exhibited activity near to the monohydrox-yl derivative. Near symmetrical tri- and symmetrical tetrahydroxylated benzophenones were determined to have greater estrogenic activity (EC50 values of e-07 M) than nonsymmetrical molecules. A comparison of estrogenicity (EC50) with acute toxicity (LC50) reveals a less than a 10-fold difference in activities for weaker estrogenic compounds. However, the more hydrophilic, stronger estrogenic compounds typically exhibit a difference of two to three orders of magnitude between EC50 and LC50 values.
Concentrations and dose rate estimates of 134137cesium and 90strontium in small mammals at chornobyl, Ukraine
Authors: Chesser Ronald K. , Sugg Derrick W , Lomakin Michael D , van den Bussche Ronald A , DeWoody J Andrew , Jagoe Charles H , Dallas Cham E , Whicker F Ward , Smith Michael H , Gaschak Sergei P , Chizhevsky Igor V , Lyabik Vitalij V , Buntova Elena G , Holloman Kevin , Baker Robert J 
Published: March 2010

Abstract
Free-ranging mammals near the Chornobyl nuclear reactor are experiencing substantial radiation dose rates from intramuscular concentrations of 134137Cs and skeletal 90Sr. Radiocesium concentrations averaged 3,200 Bq/g of dry muscle, compared to a mean of 297 Bq 90Sr/g in bone for mammals in the Exclusion Zone, a region of restricted human activity surrounding the reactor. Estimates of dose rates from intramuscular sources of radiocesium averaged 2.4 mGy/d within 8 km of the reactor and ranged as high as 60 mGy/d. Overall dose rates from internal 90Sr for mammals in the Exclusion Zone averaged 1.0 mGy/d, although doses to specific tissues are likely much higher. Mammals captured 30 km southeast of the reactor averaged only 2 Bq/g of muscle and were receiving an average of 1.4 μuGy/d from internal radiocesium. Dramatic variation exists in the spatial pattern of radiocesium in areas immediately surrounding the reactor and within and between remediated and unremediated regions. The variance of 90Sr for taxa among sites was significantly less than that for 134137Cs. Thermoluminescent dosimeters placed on free-ranging mice showed that dose rates from external sources of radiation were much greater than the dose rates from internal sources of radiocesium. Estimated dose rates in very small areas of the Chornobyl region exceed those reported to impede reproductive success in mammals.
Polychlorinated dioxins and furans in sediments at a site colonized byDreissenain western lake Ontario, Canada
Authors: Marvin Christopher H , Howell E Todd , Reiner Eric J 
Published: March 2010

AbstractPotential impacts of Dreissena on polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzofuran (PCDF) levels in sediment were investigated by comparing PCDD/PCDF levels in colonized sediment with levels in sediment in the same area that was not colonized but that was exposed to similar environmental conditions. Levels of PCDDs/PCDFs were also determined in Dreissena tissues. The particle size distribution of colonized sediment was characterized by silt-size material with peak abundance in the range of 7.5 to 20 μm, whereas noncolonized sediment was coarser in nature (30–60 μm). Total organic carbon (TOC) and concentrations of the PCDD/PCDF congener groups and individual 2,3,7,8-substituted isomers were greater in colonized sediment. A trend was observed toward decreasing concentrations of PCDF congener groups with increased chlorine substitution in mussel tissues in contrast to increasing concentrations of PCDF congener groups with increased chlorination in sediments. The trend in the PCDD congener group profile in mussel tissues appeared more similar to the profile in sediments. Areal estimates of toxicity equivalents (TEQ) in Dreissena biomass at Port Dalhousie, Ontario, Canada (approx. 1,300 pg/m2) were about 0.9% of the TEQ in the top 3 cm of sediment (approx. 135,000 pg/m2). Differences in particle size distribution and PCDD/PCDF levels between colonized and noncolonized sediment suggest that Dreissena may influence chemical and physical properties of sediment they colonize.
USE of outdoor freshwater pond microcosms: I. Microcosm design and fate of pyridaben
Authors: Rand Gary M , Clark James R , Holmes Catherine M 
Published: March 2010

Abstract
An outdoor freshwater microcosm study was conducted in which pyridaben, an insecticide-miticide, was directly applied to water to determine its fate and biological effects on an aquatic community. The following paper describes the design, specific techniques, and fate of pyridaben in microcosms including model prediction of the estimated environmental concentration, whereas the subsequent paper describes the responses of biota. An analysis of variance design was used with four treatments in which pyridaben was applied as an aqueous suspension (75% wettable powder) at three concentrations (0.34, 3.4, 34.0 μg/L) plus an untreated control to 24 microcosm tanks (23 m3). Each treatment was replicated six times. Pyridaben was applied to each microcosm once in April and once in May 1993 to simulate actual crop application. The Exposure Analysis Modeling System predicted that as a result of a drift (5.0%) exposure scenario, the half-life of pyridaben in water was 30 to 34 h. The model also predicted negligible concentrations of pyridaben in sediment after drift. Surface runoff was not considered an important source of pyridaben to aquatic systems, because the Pesticide Root Zone Model predicted a maximum runoff concentration of 0.1 μg/L. The half-life in microcosm water for the low, middle, and high treatment concentrations for both applications ranged from 11.8 to 28.5 h. After both applications at 3.4 μg/L, pyridaben was not detected in sediment within 24 h, whereas at 34.0 μg/L the half-life of pyridaben in sediment was 9.8 d.
Comparative study of toxicity testing and macroinvertebrate assessment of petroleum storage and manufacturing site and receiving water
Authors: T. Vernon Beaty  , McFee Wayne E , Flemming Charmaine A , Giffin Mark 
Published: March 2010

AbstractToxicity tests were performed on runoff associated with manufacturing activity and effluent from chemical and petroleum storage tank containment areas. Toxicity tests and macroinvertebrate surveys were used to assess the quality of receiving streams. The sensitivity of Ceriodaphnia dubia and Brachionus calyciflorus to these effluents was compared. The 95% confidence limits of the probit LC20 (concentration inversely predicted to kill 20% of test organisms), probit E100 (effect predicted by the probit model at 100% effluent), and linear E100 (effect predicted by a first-order binomial model at 100% effluent) were used as toxicity criteria and compared, and the results of effluent and receiving water toxicity tests and macroinvertebrate assessments were compared. B. calyciflorus was unaffected by effluents that were toxic to C. dubia. The toxicity criteria generally agreed, but most disagreements involved LC20s with infinite inverse confidence limits, a problem that made the LC20 impractical. Even though discharges were frequently toxic, few downstream samples were toxic, and macroinvertebrate assessments failed to detect impact at most stations. Sensitivity of macroinvertebrate assessments was adversely affected by land development around the study sites. The macroinver-tebrate indices were difficult to interpret because their variances were not known.
USE of cholinesterase in aporrectodea caliginosa (Oligochaeta; Lumbricidae) to detect organophosphate contamination: Comparison of laboratory tests, mesocosms, and field studies
Authors: Booth Lynn H , Hodge Simon , O'Halloran Kathryn 
Published: March 2010

Abstract
Acute and sublethal enzyme responses were assessed in the earthworm Aporrectodea caliginosa (Savigny) exposed to chlorpyrifos and diazinon in the laboratory, mesocosms, and field exposures. The aim of this work was to evaluate whether cholinesterase (ChE) activity has potential as a biomarker of organophosphate exposure in earthworms. No mortality or population changes were found at the recommended field application rates of the pesticides in the three experimental systems. Cholinesterase activity was severely inhibited in earthworms exposed to sublethal doses in laboratory tests. However, no effects of the pesticides on ChE were found in the mesocosm or natural worm populations.
Temporal trends in ethoxyresorufin-o-deethylase activity of brook trout (Salvelinus fontinalis) fed 2,3,7,8-tetrachlorodibenzo-p-dioxin
Authors: Cormier Susan M , Millward Michael R , Mueller Cornelia , Subramanian Bhagya , Johnson Rodney D , Tietge Joseph E 
Published: March 2010

AbstractChanges in ethoxyresorufin- O-deethylase (EROD) activity were monitored through an extended 6-month dietary exposure to determine the relationship between EROD activity and uptake of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in brook trout, Salvelinus fontinalis. Brook trout were fed labeled TCDD during a 4-week loading phase and an 11-week maintenance phase to achieve whole-body concentrations of 0, 75, 150, 300, 600, and 1,200 pg TCDD/g fish. A spawning phase followed during which no TCDD was introduced. The TCDD had an extended half-life, with maximal levels detected in the late loading-early maintenance phases and 81 d after TCDD had been removed from the diet. Accumulation in liver increased as whole-body target concentration increased but was generally less than half of anticipated whole-body target concentrations. The EROD activity demonstrated a dose-dependent increase. Positive correlations were observed between EROD activity and TCDD body burdens for both males and females. For males, maximal induction was attained early in the maintenance phase and maintained during latter phases. For females, induction was characterized by a biphasic pattern. Maximal induction was attained during late loading-early maintenance, with an attenuated response observed just before spawning. In addition, the induction response was modulated by sex, as induction was lower in females when compared with males. If sexual biases are considered, increased EROD activity may serve as an indicator of level of TCDD exposure and a sublethal predictor of effects of exposure.
Behavior of trace metals in the sediment pore waters of intertidal mudflats of a tropical wetland
Authors: Yu Kai-Tung , Lam Michael Hon-wah , Yen Yu-Fong , Leung Amy PK 
Published: March 2010

Abstract
Vrtical profiles ofdissolvedCd, Cr, Cu, Pb, Zn, Fe, and Mn in the sediment pore waters of the intertidal mudflats of the Mai Po and Inner Deep Bay Ramsar Site of Hong Kong, People's Republic of China, were measured using the polyacrylamide gel diffusive equilibration thin film (DET) technique. The ranges of concentrations of dissolved Cd, Cr, Cu, Pb, Zn, Fe, and Mn in the pore water of the top 0 to 20 cm of sediment were 2.2 to 10.0 nM, 346.0 to 950.0 nM 243.8 to 454.8 nM, 23.2 to 51.2 nM, 39.8 to 249.5 μM, and 13.4 to 20.7 μM, respectively. Enrichment of these trace metals was observed in the upper 0- to 7-cm layer. Profiles of conditional distribution coefficient, log(KD), of the trace metals and results of multiple regression analysis have revealed that reduction of Mn (hydrous) oxides was the major remobilization mechanism for Cd, Cr, Cu, Pb, and Zn in the mudflats. Benthic diffusive fluxes of these trace metals from the mudflats were also estimated on the basis of the concentration gradients of trace metals between surface sediments and the overlying water column. The magnitude of the estimated diffusive fluxes followed the order Zn &gt; Cr &gt; Cu &gt; Pb &gt; Cd.
Impact of storm-water outfalls on sediment quallity in corpus Christi Bay, Texas, USA
Authors: Carr R Scott , Montagna Paul A , Biedenbach James M , Kalke Rick , Kennicutt Mahlon C , Hooten Russell , Cripe Geraldine 
Published: March 2010

Abstract
To determine the quality of sediments and extent of contaminant impacts, a Sediment Quality Triad (SQT) study was conducted at 36 sites in the Corpus Christi Bay, Texas, USA, system. Fifteen of the 36 sites were located near storm-water outfalls, but 13 other sites (i.e., industrial and domestic outfalls, oil field–produced water discharges, and dredging activity) and eight reference sites were also evaluated. Sediment samples were collected and analyzed for physical–chemical characteristics, contaminant concentrations (metals, polycyclic aromatic hydrocarbons [PAHs], polychlorinated biphenyls [PCBs], and pesticides), toxicity (amphipod and mysid solid phase and sea urchin pore-water fertilization and embryological development tests), and a benthic index of biotic integrity (BIBI) composed of 10 independent metrics calculated for each site. This large data matrix was reduced using multivariate analysis to create new variables for each component representing overall means and containing most of the variance in the larger data set. The new variables were used to conduct the correlation analysis. Toxicity was significantly correlated with both chemistry and ecological responses, whereas no correlations between the benthic metrics and sediment chemistry were observed. Using the combined information from the SQT, four of the five most degraded sites were storm-water outfall sites. Although estuaries are naturally stressful environments because of salinity and temperature fluctuations, this ecosystem appears to have been compromised by anthropogenic influences similar to what has been observed for other heavily urbanized bay systems along the Texas and Gulf coast.
Variables determining the impact of diazinon on aquatic insects: Taxon, developmental stage, and exposure time
Authors: Stuijfzand Suzanne C , Poort Liesbeth , Greve Gerdit D , van der Geest Harm G , Kraak Michiel H S 
Published: March 2010

Abstract
Several variables determine the impact of a pesticide onaquatic invertebrates. In this study, aquatic insects weresubjected to the common insecticide diazinon; we analyzed the variables taxon, developmental stage, and exposure time. Effects of diazinon on the caddis fly Hydropsyche angustipennis and the midge Chironomus riparius were determined in the laboratory during different exposure times (48 and 96 h) using mortality, activity, and growth as end points. Last instars of both species displayed a clear behavioral response at concentrations much lower than those affecting survival. Doubling the exposure time from 2 to 4 d decreased survival of midges and caddis flies by a factor 1.4 to 8.4. The 96-h 50% lethal concentrations were: 1.3 μg/L (first instar of the caddis fly), 29 μg/L (fifth instar of the caddis fly), 23 μg/L (first instar of the midge) and 167 μg/L (fourth instar of the midge). Within the spectrum of tested insects (nine species for which 48-h 50% lethal concentrations have been reported in the literature), H. angustipennis is the second most sensitive, and C. riparius the most tolerant species. However, the ranking of species strongly depends on the developmental stage; differences between species are often smaller than differences between instars of one species. The large difference in sensitivities between young and old larvae imply that the impact of a pesticide strongly depends on the season of occurrence. Runoff from pesticide applications on crops is more likely to occur in spring and summer and may have a relatively greater impact on insect communities since young larvae prevail in these seasons. In addition, recovery of typical riverine insects such as H. angustipennis from incidental exposure will be slow, considering their relatively long life cycle.
Accumulation of silver from the diet in two marine benthic predators: The snow crab (Chionoecetes opilio) and American plaice (Hippoglossoides platessoides)
Authors: Rouleau Claude , Gobeil Charles , Tjälve Hans 
Published: March 2010

Abstract
The kinetics and fine-scale tissue distribution of a single dose of 110mAg ingested with food were determined in snow crab and American plaice through the techniques of in vivo gamma counting and whole-body autoradiography. Metal that was retained after the first 3 d was distributed in all the soft tissues of snow crab, whereas it concentrated in gut, liver, and gallbladder of the American plaice. In snow crab, the biological half-life of retained Ag, which represented 67–100% of the ingested dose, was greater than 1000 d. In contrast, in American plaice the retained fraction represented only 4–16% of the ingested dose and the biological half-life ranged from 13 to 102 d. Modeling the trophic accumulation of Ag for snow crab and American plaice living in the St. Lawrence Estuary, assuming realistic values for food ingestion rates and Ag concentration in benthic organisms of lower trophic levels, reveals that continuous feeding on Ag-contaminated prey would result in much higher metal levels in the snow crab than in the American plaice. Measurement of Ag concentrations in snow crab and American plaice from the St. Lawrence Estuary, an environment receiving significant inputs of anthropogenic Ag, confirmed this prediction. The similarity between laboratory-based predictions and field data strongly suggests that predation is the major transfer route of Ag towards these marine benthic predators.
Dose-dependent stimulation of hepatic retinoic acid hydroxylation/oxidation and glucuronidation in brook trout,Salvelinus fontinalis, after exposure to 3,3′,4,4′-tetrachlorobiphenyl
Authors: Boyer Patrick M , Ndayibagira Aristocle , Spear Philip A 
Published: March 2010

AbstractExtremely low stores of vitamin A have been reported in fish and birds inhabiting regions contaminated by coplanar polychlorinated biphenyls (PCBs) and other organochlorines, suggesting many possible effects on retinoid biochemical pathways. Metabolic imbalances associated with biologically active retinoids (e.g., retinoic acid) could be associated with teratogenesis, edema, growth inhibition, reproductive impairment, immunosuppression, and susceptibility to cancer. Sexually mature brook trout were injected intraperitoneally with the coplanar PCB 3,3′,4,4′-tetrachlorobiphenyl (TCBP) and again 4 weeks later. At 8 weeks, retinoic acid metabolism was measured in liver microsomes. To our knowledge, retinoic acid conjugation by UDP-glucuronyltransferase is described here for the first time in fish. A substantial rate of glucuronidation was detected in the microsomes from control brook trout, which tended to increase over the dose range of TCBP. Glucuronidation was significantly greater in fish receiving the 10 μg/g body weight dose level. Metabolism through the cytochrome P450 system was also dose-dependent, resulting in significantly greater production of 4-hydroxyretinoic acid at the 10 μg/g dose level. In contrast, subsequent oxidation to 4-oxo-retinoic acid was greatest at the 1 μg/g dose level and did not increase further at higher doses. Liver stores of dehydroretinyl palmitate/oleate were significantly decreased at the 5 and 10 μg/g dose levels.