bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resistance to cadmium and parasite infection are inversely related in two strains of a freshwater gastropod
Authors: Salice Christopher J. , Roesijadi Guritno 
Published: March 2010

Abstract
Phenotypes that are either resistant or susceptible to infection by the trematode parasite Schistosoma mansont exist in the tropical freshwater snail Biomphalaria glabrata. We tested the hypothesis that a cost of parasite resistance in B. glabrata is greater sensitivity to cadmium toxicity, using parasite-resistant and parasite-susceptible strains exposed to cadmium in the laboratory. Survival analysis showed that time to death for cadmium was significantly shorter in eggs, juveniles, and adults of the parasite-resistant BS90 strain in comparison with the parasite-susceptible NMRI strain. Cadmium exposure increased time to hatch in both strains, but the effect was greater in BS90. Percentage hatch decreased with increased cadmium; BS90 was again more sensitive than NMRI. Comparison of the median effective concentration (EC50) for hatching and median lethal concentrations (LC50s) for survival of juveniles and adults showed that the order for cadmium resistance was adults &gt; juveniles &gt; eggs in NMRI and adults &gt; eggs &gt; juveniles in BS90. Cadmium resistance of F1 and F2 progeny of BS90/NMRI crosses was intermediate to that of parental strains. Numerical estimates indicated that a single genetic factor was responsible for the difference in cadmium resistance in the two strains. These findings were consistent with the hypothesis that greater sensitivity to cadmium is a cost of resisting parasitic infection.
A field validation of two sediment-amphipod toxicity tests
Authors: Perraro Steven P. , Cole Faith A. 
Published: March 2010

AbstractA field validation study of two sediment-amphipod toxicity tests was conducted using sediment samples collected subtidally in the vicinity of a polycyclic aromatic hydrocarbon (PAH)-contaminated Superfund site in Elliott Bay (WA, USA). Sediment samples were collected at 30 stations with a 0.1 m2 grab from which subsamples were taken for sediment toxicity testing and geochemical and macrofaunal analyses. Standard 10-d sediment-amphipod toxicity tests were conducted with Rhepoxynius abronius and Leptocheirus plumulosus. Sediments were analyzed for 33 PAHs, pentachlorophenol, polychlorinated biphenyls, acid-volatile sulfide, simultaneously extracted metals (Cd, Cu, Zn, Pb, Ni), total organic carbon, and grain size. Sediment temperature, oxygen-reduction potential, water depth, and interstitial water salinity were also measured. Polycyclic aromatic hydrocarbons, quantified as total PAH toxic units (TUPAH), were confirmed to be an important common causal agent of the changes in the two toxicity test (% survival R. abronius, % survival L. plumulosus) and five macrofaunal community (number of species, S; numerical abundance, A; total biomass, B; Swartz's dominance index, SDI; Brillouin's index, H) endpoints. Two other macrofaunal community metrics (the complement of Simpson's index, 1 — SI, and McIntosh's index, MI) were less sensitive to TUPAH than the two toxicity test endpoints. The sensitivities of R. abronius and L. plumulosus to TUPAH were statistically indistinguishable. Field validations were conducted by testing the association between or among each toxicity test endpoint, each of seven macrofaunal community metrics (S, A, B, SDI, H, 1 — SI, MI), and TUPAH by (1) Spearman's coefficient of rank correlation, (2) Kendall's coefficient of concordance, (3) G tests of independence, and (4) regression analysis. Some field validations based on multivariable tests of association (e.g., points 2 and 3) among toxicity test, field, and stressor endpoints produced false positive results. Both toxicity test endpoints were validated as indicators of changes in S, A, SDI, and H by all the methods tested. The resolution power of the relationships between the laboratory toxicity test and macrofaunal field endpoints was low (⩽ three classes) but sufficient to discriminate ecologically important effects. We conclude that standard sediment-amphipod toxicity tests are ecologically relevant and that, under the proper conditions, their results can be used for lab-to-field extrapolation.
Hydrocarbon composition and toxicity of sediments following theExxon valdezoil spill in Prince William Sound, Alaska, USA
Authors: Page David S. , Boehm Paul D. , Stubblefield William A. , Parker Keith R. , Gilfillan Edward S. , Neff Jerry M. , Maki Alan W. 
Published: March 2010

AbstractAn 11-year study of the 1989 Exxon Valdez oil spill found that spill residues on the oiled shorelines rapidly lost toxicity through weathering. After 1990, toxicity of sediments remained at only a few heavily oiled, isolated locations in Prince William Sound (AK, USA), as measured by a standard amphipod bioassay using Rhepoxynius abronius. Data from 648 sediment samples taken during the 1990 to 1993 period were statistically analyzed to determine the relationship between the total concentration of 39 parent and methyl-substituted polycyclic aromatic hydrocarbons (defined as total polycyclic aromatic hydrocarbons [TPAH]) and amphipod mortality and the effect of oil weathering on toxicity. A logistic regression model yielded estimates of the lower threshold, LC10 (lethal concentration to 10% of the population), and LC50 (median lethal concentration) values of 2,600, 4,100, and 10,750 ng/g TPAH (dry wt), respectively. Estimates of the threshold and LC50 values in this field study relate well to corresponding sediment quality guideline (SQG) values reported in the literature. For sediment TPAH concentrations &gt;2,600 ng/g, samples with high mortality values (&gt;90%) had relatively high fractions of naphthalenes and those with low mortality (&lt;20%) had relatively high fractions of chrysenes. By 1999, the median sediment TPAH concentration of 117 ng/g for the post-1989 worst-case sites studied were well below the 2,600 ng/g toxicity threshold value, confirming the lack of potential for long-term toxic effects. Analysis of biological community structure parameters for sediment samples taken concurrently found that species richness and Shannon diversity decreased with increasing TPAH above the 2,600 ng/g threshold, demonstrating a correspondence between sediment bioassay results and biological community effects in the field. The low probability of exposure to toxic concentrations of weathered spill residues at the worst-case sites sampled in this study is consistent with the rapid overall recovery of shoreline biota observed in 1990 to 1991.
An assessment of in vitro androgenic activity and the identification of environmental androgens in United Kingdom estuaries
Authors: Thomas Kevin V. , Hurst Mark R. , Matthiessen Peter , McHugh Mathew , Smith Andy , Waldock Michael J. 
Published: March 2010

Abstract
Environmental androgens are a group of compounds that to date have received very little attention. In this study, a yeast-based androgen screen (YAS) was used to determine the level of in vitro androgenic activity in seven United Kingdom estuaries. Surface water, sediment pore water, and sediment particulate material solvent extracts collected from Southampton Water, the Thames, Mersey, Tees, Tyne, Clyde, and Forth were tested for in vitro androgenic activity. Eleven of the 41 surface water samples collected displayed androgenic activity &gt;2 ng dihydrotestosterone (DHT) equivalents/L (3–9 ng DHT/L), while eight of the 39 sediment pore waters collected showed activity &gt;45 ng DHT/L (51–187 ng DHT/L). High levels of androgenic activity were determined in the solvent extracts of sediments, with 10 of 39 samples exhibiting a level of androgenic activity &gt;454 ng DHT/kg (1,020-15,300 ng DHT/kg). In vitro YAS testing of five selected sewage treatment works (STW) effluents entering these estuaries showed that measurable levels (34–635 ng DHT/L) of androgenic activity were observed in those receiving only primary treatment (Howdon STW and Irvine Valley Sewer) at the time of the survey. A toxicity identification evaluation (TIE) study of Irvine Valley Sewer effluent using the YAS assay was used to identify the natural steroids/steroid metabolites dehydrotestosterone, androstenedione, androstanedione, 5β-androstane-3α, 11β-diol-17-one, androsterone, and epi-androsterone as responsible for 99% of the in vitro activity determined in the effluent.
Application of postexposure feeding depression bioassays withDaphnia magnafor assessment of toxic effluents in rivers
Authors: McWilliam Ruth A. , Baird Donald J. 
Published: March 2010

AbstractA bioassay that used postexposure feeding depression in Daphnia magna Straus as an endpoint previously had been developed under laboratory conditions. Laboratory studies revealed that this was a sensitive, robust endpoint, which could potentially be used in an in situ bioassay. This study adapted the laboratory bioassay for use in the field and deployed D. magna in situ at four known or suspected contaminated and reference sites. The bioassay was demonstrated to be reliable for use in the field because more than 90% of test organisms were recovered live from the test chambers after exposure allowing feeding rates to be measured after exposure. At each of the contaminated sites, significant depressions in postexposure feeding rates were recorded. Although depressions in postexposure feeding rates were apparent at all contaminated sites, with the exception of Langholm, no impacts were detected on the benthic macroinvertebrate community, when using the Biological Monitoring Working Party scoring system. This demonstrated that during this study, post-exposure feeding depression was a more reliable and sensitive endpoint to use to detect toxicity than were changes in community structure. Therefore, the postexposure feeding depression bioassay can offer a sensitive, robust, ecologically relevant diagnostic endpoint for use in water-quality assessment schemes.
Comparison of pesticide root zone model 3.12: Leaching predictions with field data
Authors: Russell Mark H. , Jones Russell L. 
Published: March 2010

Abstract
As part of a process to improve confidence in the results of regulatory modeling, predictions of the pesticide root zone model (PRZM) 3.12 were compared with measured data collected in nine different field leaching studies. Reasonable estimates of leaching were obtained with PRZM 3.12 in homogeneous soils where preferential flow is not significant. The PRZM 3.12 usually did a good job of predicting movement of bromide in soil (soil and soil pore-water concentrations were generally within a factor of two of predicted values). For simulations based on the best choices for input parameters, predictions of soil pore-water concentrations for pesticides were usually within a factor of three and soil pore-water estimates within a factor of 11. When the model input parameters were calibrated to improve the simulation of hydrology, predicted pesticide concentrations in soil pore water were usually within a factor of two of measured concentrations. Because of the sensitivity of leaching to degradation rate, the most accurate predictions were obtained with pesticides with relatively slow degradation rates. When conservative assumptions were used to define input pesticide parameters, predictions of pesticide concentrations were usually a factor of two greater than when using the best estimate of input parameters without any built-in conservatism.
Distribution of cytochrome P4501A1–inducing chemicals in sediments of the Delaware River-Bay system, USA
Authors: McCoy Daniel L. , Jones Jennifer M. , Anderson Jack W. , Harmon Michelle , Hartwell Ian , Hameedi Jawed 
Published: March 2010

Abstract
The Delaware River-Bays system, USA, was the subject of a study by the National Oceanic and Atmospheric Administration that involved chemical and biological analyses, including the use of the biomarker P450 human reporter gene system (HRGS) to document the occurrence and distribution of cytochrome P450 (CYP) 1A1-inducing compounds. Sediment extracts from 81 locations along the Delaware River, Delaware Bay and immediate coastline were tested by utilizing HRGS as an inexpensive screening test, and were also analyzed for polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls, with selected stations analyzed for dioxins and furans. Benthic community degradation has been observed when benzo[a]pyrene equivalents (BaPEq) exceeded 60 μg/g. The average levels of BaPEq for the largely industrialized upper, middle, and lower regions of the Delaware River were 107, 62, and 5 μg/g, respectively, excluding outliers. Tributaries leading into river averaged 21 μg/g BaPEq, whereas the central Bay and open coast had relatively low values (2.0 and 0.5 μg/g BaPEq, respectively). The HRGS values were highly correlated with total PAHs measured in the same sediment samples (r2 = 0.81). Overall, contamination levels consistently decreased from the upper and middle river sites as collection locations progressed down through the lower river and bay to the coast. Thus, despite the relatively high contaminant load in the river system, Delaware Bay and the immediate coastline seem to have relatively low levels of contaminants, and, therefore, impacts on the benthic organisms in the bay and coast would not be expected from these findings.
The physiology of copper tolerance in fathead minnows: Insight from an intraspecific, correlative analysis
Authors: Kolok Alan S. , Hartman Melissa M. , Sershan John 
Published: March 2010

AbstractExposure to a sublethal (150 μg/L) concentration of copper (Cu) can reduce the critical swimming speed (Ucrit) of some fathead minnows (Pimephales promelas). The reduction is not consistent from one individual to the next, however, as some individuals experience dramatic reductions, while others maintain performance at preexposure levels. The objective of this experiment was to determine whether fish that experienced dramatic reductions in Ucrit were physiologically different from more resistant individuals. Individual variation in gill Na+-K+ activated adenosine triphosphatase (ATPase) activity was not significantly associated with variation reduction in Ucrit. Whole-body Cu was significantly related to reduction in Ucrit, and the relationship was surprisingly negative with the greatest reductions in Ucrit occurring in the fish with the lowest whole-body Cu concentrations. Whole-body Na+ was also significantly related to reduction in Ucrit, as the fish with the greatest whole-body Na+ experienced the smallest reduction in Ucrit. Fathead minnows are differentially susceptible to sublethal concentrations of Cu; this difference appears to be related to Na+ ionoregulation as well as the capacity of the fish to accumulate Cu.
Effect of soil copper content and pH on copper uptake of selected vegetables grown under controlled conditions
Authors: Ginocchio Rosanna , Rodríguez Patricio H. , Badilla-Ohlbaum Ricardo , Allen Herbert E. , Lagos Gustavo E. 
Published: March 2010

Abstract
A one-year greenhouse experiment was conducted to study the transfer of copper from contaminated agricultural soils to edible and nonedible structures of lettuce, tomato, and onion plants. Study soils were selected from two basins of central Chile (Santiago and Cachapoal) to represent two similar total soil copper gradients with different pH values. Results showed that free ionic Cu and Cu in saturation extracts were very low in comparison to total Cu contents of study soils (&lt;0.002% and &lt;0.04%, respectively). The concentrations of free ionic copper and of copper in saturation extracts were correlated to total Cu levels and to soil pH. Mean copper concentrations were higher in lettuce than in tomato and onion plants and in vegetables grown on acidic soils of the Cachapoal basin. However, copper levels in edible tissues of tomato and lettuce plants were similar to copper levels described for plants grown on unpolluted soils except for onion bulbs, which had higher values. This indicates that copper translocation to edible, above-ground structures seemed to be well regulated, as their concentrations were fairly constant. The study shows that Cu concentration in study vegetables depends on various factors, including plant species and tissue; site-specific soil factors, such as pH, organic matter, dissolved organic carbon, and conductivity; and several Cu pools, such as total, extractable, and free ionic Cu. Thus, our results support the intensity/capacity concept in that Cu concentration in plants or plant tissues depends not only on the availability of free copper ions in soil solution but also on other soil copper pools that supply the element to the soil solution.
Analysis of trace organic contaminants in sediment, pore water, and water samples from Onsan Bay, Korea: Instrumental analysis and in vitro gene expression assay
Authors: Koh Chul-Hwan , Khim Jong Seong , Villeneuve Daniel L. , Kannan Kurunthachalam , Giesy John P. 
Published: March 2010

AbstractPersistent organic pollutants and alkylphenols (APs) were determined in sediment and water samples from Onsan Bay, Korea, by using instrumental analysis and in vitro gene expression cell bioassay. Polycyclic aromatic hydrocabons (PAHs) were the predominant compounds in sediments with concentrations as great as 573 ng/g dry weight. The PAH concentrations were elevated in sediment from inland rivers that flow through Onsan City (mean: 116 ng/g dry wt) and discharge into Onsan Bay. Concentrations of polychlorinated biphenyls (PCBs) in sediments ranged from &lt;1.00 to 56.2 ng/g dry weight. Among different organochlorine (OC) pesticides analyzed (hexachlorobenzene, hexachlorocyclohexanes, chlordanes, and DDTs), DDT concentrations were the greatest, ranging from &lt;0.01 to 7.58 ng/g dry weight. The spatial gradient of contaminant concentrations suggested that streams and rivers are the major sources of PCBs, PAHs, and APs to the bay. Maximum concentrations of nonylphenol, octylphenol, and bisphenol A in sediments were 860, 11, and 204 ng/g dry weight, respectively. Screening of Onsan Bay sediment samples for dioxinlike activity with the H4IIE-luc in vitro cell bioassay revealed that 17 of 22 samples contained significant dioxinlike activity. Further fractionation of sediment extracts indicated that mid-polar and more polar fractions were responsible for the significant dioxinlike activity. Based on a mass balance analysis, PAHs apparently accounted for only a small portion of dioxinlike responses elicited by sediment extracts. Only one raw extract of sediment elicited a significant estrogenic response by MVLN cells. The combination of instrumental analysis and in vitro bioassay was useful to assess sediment quality and characterize the causative agents or potential toxic compounds present.
Nonylphenol polyethoxylate adjuvant mitigates the reproductive toxicity of fomesafen on the freshwater snailLymnaea stagnalisin outdoor experimental ponds
Authors: Jumel Audrey , Coutellec Marie-Agnes , Cravedi Jean-Pierre , Lagadic Laurent 
Published: March 2010

AbstractThe influence of nonylphenol polyethoxylates (NPEO), formulated astheadjuvant Agral® 90, on the effects of the diphenyl ether herbicide fomesafen in the pond snail Lymnaea stagnalis was investigated, with particular attention to the reproductive performances and underlying energetic and hormonal processes. Separate short-term exposures to low concentrations of fomesafen and fomesafen-Agral mixture were performed in the laboratory. Outdoor experimental ponds (mesocosms) were used for long-term exposures to higher chemical concentrations. At the concentrations used in the studies, NPEO were known as nontoxic in L. stagnalis. Fomesafen was mixed with the adjuvant in the 3:7 ratio recommended for agricultural uses (nominal herbicide concentrations of 22 and 40 μg/L in laboratory and mesocosm, respectively). In mesocosms, multiple application of fomesafen, leading to maximal herbicide concentrations of 60.33 ± 2.68 μg/L in water, resulted in reduced number of egg masses and altered glycogen metabolism in contaminated snails. These changes, as well as affected steroid-like levels in fomesafen-exposed snails, support the hypothesis of impaired neuroendocrine functions. When Agral 90 was added to the herbicide, results obtained in mesocosms showed that the adjuvant softened the impact of fomesafen. In mesocosms treated with the fomesafen-Agral mixture, significantly lower herbicide levels were found in the water (30.33 ± 14.91 μg/L at the end of the contamination period). Consequently, internal exposure of the snails to fomesafen was reduced when the herbicide was mixed with the adjuvant. Mitigation of the effects of fomesafen by the adjuvant may therefore result from nonionic surfactant activity of NPEO that prevented fomesafen from reaching the snails.
Demographic responses of the polychaeteDinophilus gyrociliatusto chromium exposure
Authors: Mauri Marina , Simonini Roberto , Baraldi Elena 
Published: March 2010

AbstractThe effects of chromium on the life history and demography of Dinophilus gyrociliatus (Polychaeta) were studied on a control and three treated cohorts kept in artificial seawater enriched with nominal concentrations of chromium at 1.0, 1.4, and 1.6 μg/ml. Survival and fecundity were significantly reduced by chromium. Fecundity was higher in the chromium treatments than in the control group at the beginning of the reproductive period; however, overall, the highest fecundity was observed in the control. Life expectancy, net growth rate, and generation time were also significantly reduced by chromium. The population growth rate (&LD) was higher in the treated animals than in the controls. The differences in &LD between the treated animals and the controls (ΔΛ) were almost completely due to the differences in the life tables observed during the first three weeks of life. The differences in survival between the treated and control animals did not contribute to ΔΛ. The contribution to ΔΛ of the slight increase in age-specific fecundity in the early reproductive events compensated for the marked decrease in overall fecundity in the treated animals. The complex effects of chromium enrichment on D. gyrociliatus underline the importance of analyzing both individual and population responses when assessing the effects of pollutants on organisms. Our results confirm that D. gyrociliatus might serve as an indicator species in confined areas of polluted seawater such as lagoons and harbors.