bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sampling in the Great Lakes for pharmaceuticals, personal care products, and endocrine-disrupting substances using the passive polar organic chemical integrative sampler
Authors: Li Hongxia , Helm Paul A. , Metcalfe Chris D. 
Published: March 2010

Abstract
The passive polar organic chemical integrative sampler in the pharmaceutical configuration (i.e., pharmaceutical-POCIS) was calibrated for sampling at water temperatures of 5, 15 and 25°C to determine the influence of temperature on chemical-specific sampling rates (RS), thus providing more robust estimates of the time-weighted average concentrations of pharmaceuticals and personal care products (PPCPs) and endocrine-disrupting substances (EDS) in surface water. The effect of water temperature and flow on the RS of these analytes was evaluated in the laboratory with a static system. The loss of the test compounds from water by uptake into POCIS was linear over an 8-d period, and these experimental data yielded RS values in the range of 0.07 to 2.46 L/d across the temperature range for the 30 compounds tested. Water temperature and flow influenced POCIS uptake rates, but these effects were relatively small, which is consistent with the theory for uptake into POCIS samplers. Therefore, under a narrow range of water temperatures and flows, it may not be necessary to adjust the RS for POCIS. Except for acidic drugs and sulfonamide antibiotics, RS values were positively correlated with octanol–water partition coefficients (log KOW) of the test compounds. A linear relationship was also observed between RS and chromatographic retention times on a C18 reversed-phase column. These observations may provide a rapid method for estimating the RS of additional chemicals in the POCIS. The application of the RS to POCIS deployed for one month in Lake Ontario, Canada, during the summers of 2006 and 2008 yielded estimates of PPCP and EDS concentrations that are consistent with conventional concentration measurements of these compounds in Lake Ontario surface water. Environ. Toxicol. Chem. 2010;29:751–762. © 2009 SETAC
Leaching potential of nonsteroidal anti-inflammatory drugs in soils
Authors: Xu Jian , Wu Laosheng , Chen Weiping , Chang Andrew C. 
Published: March 2010

Abstract
Nonsteroidal anti-inflammatory drugs (NSAIDs) in soils resulting from application of municipal wastewater or biosolids may migrate through soils intact or be transformed and reach groundwater. In the present study, the leaching potential of four NSAIDs (ibuprofen, naproxen, ketoprofen, and diclofenac sodium) in three U.S. cropland soils was evaluated, and the effect of CaCl2 solution (as an index of salinity), dissolved organic matter (DOM), and polyacrylamide (PAM) amendment was investigated. The soils were spiked with selected NSAIDs, incubated for 24 h followed by 7-d storage in glass flasks, and then packed into stainless steel columns and leached with deionized water (DIW), 10 mM CaCl2, DOM (DOC 34 mg/L), and PAM solution (1.0 mg/L) by gravity. Initial concentrations of ibuprofen, naproxen, ketoprofen, and diclofenac sodium in the three packed soils were 1.93 to 2.07, 1.74 to 2.27, 1.79 to 2.16, and 1.99 to 2.13 mg/kg, respectively. Maximum concentrations of the above NSAIDs in column effluents were 1.23, 0.92, 0.69, and 1.12 mg/L, respectively, when the soil was leached with 10 pore volumes of water, which occupied 17.4, 11.1, 9.6, and 15.2% of the total chemicals in each soil column. Dissolved organic matter or PAM solution did not facilitate the NSAIDs release from soils. The CaCl2 solution, however, reduced the amounts of NSAIDs leached from all three soils. Leaching of NSAIDs differed among the three tested soils. The results suggest that the leaching of NSAIDs through soil to water is significant, and the mobility of NSAIDs in soil is related to their chemicals' characteristics (such as pKa values) and soil properties (such as soil organic matter and clay content). Amending soil with DOM or PAM does not significantly affect the leaching behavior of NSAIDs in soil, whereas increasing the salinity of the irrigation water may decrease the extent of contamination of groundwater posed by NSAIDs. Environ. Toxicol. Chem. 2010;29:800–807. © 2009 SETAC
Volatilization of monoaromatic compounds (benzene, toluene, and xylenes; BTX) from gasoline: Effect of the ethanol
Authors: Cagliari Jóice , Fedrizzi Francieli , Rodrigues Finotti Alexandra , Echevenguá Teixeira Cláudia , do Nascimento Filho Irajá 
Published: March 2010

Abstract
The main objective of present study was to assess the evaporation profile of monoaromatic compounds, namely, benzene, toluene, and xylenes (BTX) from gasoline–ethanol-blend fuels. The vapors from two river sand columns contaminated with gasoline and gasoline–ethanol were monitored for 77 d. Standards mixtures (batch tests) of benzene, toluene, and xylenes with different ethanol contents were also analyzed for evaporation rates studies. The instrumental analysis was performed via gas chromatography. The concentration of benzene in the vapor phase of the gasoline–ethanol column was decreased by 89.09%, considering the entire experimental period, whereas the toluene and xylenes concentrations were increased by 239.34 and 251.78%, respectively. In the batch tests, the benzene concentration in the vapor phase varied from 0.4 to 0.9 mg/L for ethanol concentrations (v/v) of 5 and 10%, respectively. For ethanol concentrations higher than 10%, no important changes in the benzene concentration were observed. The toluene exponentially increases between 20 and 30% ethanol concentration. and the maximum concentration of xylenes was observed when the ethanol concentration was 20% (v/v). These results suggest that the benzene evaporation behavior is preferentially affected by the interactions among ethanol and other aromatic compounds rather than the ethanol concentration itself. The evaporation behaviors of toluene and xylenes are directly dependent on the ethanol content. Environ. Toxicol. Chem. 2010;29:808–812. © 2009 SETAC
Bioaccumulation and biotransformation of pyrene and 1-hydroxypyrene by the marine whelk Buccinum undatum
Authors: Beach Daniel G. , Quilliam Michael A. , Rouleau Claude , Croll Roger P. , Hellou Jocelyne 
Published: March 2010

Abstract
The fates of a phenolic contaminant and its hydrocarbon precursor have rarely been compared, especially in an invertebrate species. Two groups of Buccinum undatum were exposed to equimolar amounts of pyrene and 1-hydroxypyrene over 15 d through their diets. Tissue extracts from the muscle and visceral mass were analyzed by liquid chromatography with fluorescence and mass spectrometry detection. Nine biotransformation products were detected in animals from both exposures. These included 1-hydroxypyrene, pyrene-1-sulfate, pyrene-1-glucuronide, pyrene glucose sulfate, two isomers each of pyrenediol sulfate and pyrenediol disulfate, and one isomer of pyrenediol glucuronide sulfate. These compounds represent a more complex metabolic pathway for pyrene than is typically reported. Diconjugated metabolites were as important in animals exposed to pyrene as in those exposed to 1-hydroxypyrene. Biotransformation products represented &gt;90% of the material detected in the animals and highlight the importance of analyzing metabolites when assessing exposure. A mean of only 2 to 3% of the body burden was present in muscle compared with the visceral mass of both groups. The analytical methods were sufficiently sensitive to detect biotransformation products both in laboratory control whelks and in those sampled offshore. The tissue distribution of [14C]pyrene was also studied by autoradiography. Radioactivity was present primarily in the digestive and excretory system of the whelks and not in the gonads or muscle tissue. Environ. Toxicol. Chem. 2010;29:779–788. © 2009 SETAC
Potato (Solanum tuberosum) greenhouse tuber production as an assay for asexual reproduction effects from herbicides
Authors: Olszyk David , Pfleeger Thomas , Lee E. Henry , Plocher Milton 
Published: March 2010

Abstract
The present study determined whether young potato plants can be used as an assay to indicate potential effects of pesticides on asexual reproduction. Solanum tuberosum (Russet Burbank) plants were grown from seed pieces in a mineral soil in pots under greenhouse conditions. Plants were treated with herbicides (cloransulam, dicamba, glyphosate, imazapyr, primsulfuron, sulfometuron, or tribenuron) at simulated drift levels [≤0.1 × standard field application rates (f.a.r.)], approximately 14 d after emergence (DAE). Plant height was measured approximately 14 d after treatment (DAT). Production of small tubers and shoot dry weight were determined at approximately 28 DAT. Imazapyr, sulfometuron, and tribenuron caused significant reductions in tuber fresh weight, with the effective concentrations producing a 25% potato tuber fresh weight (EC25) of 0.00038, 0.0016, and 0.0021 × f.a.r. of 1,124, 52, and 9 g active ingredient hectare−1 (g a.i. HA−1), respectively. Primisulfuron, dicamba, and cloransulam also significantly reduced tuber fresh weight, but with higher EC25 values of 0.011, 0.07, and 0.010 to 0.2 × f.a.r. of 40, 558, and 18 g a.i. HA−1, respectively. Glyphosate had little effect on tuber fresh weight, with a significant reduction in only one experiment. Sulfometuron reduced tuber fresh weight at an EC25 value lower than the EC25 values for shoot dry weight or plant height. For other herbicides, the reduction in tuber fresh weight occurred within the range of EC25 values for other responses. Although additional experiments are required to develop further a phytotoxicity test, these results indicated that tuber production in young potato plants (harvested approximately 42 DAE) may be an effective assay for below-ground asexual reproductive responses to herbicides, especially acetolactate synthase inhibitors. Environ. Toxicol. Chem. 2010;29:111–121. © 2009 SETAC
Site-specific probabilistic ecological risk assessment of a volatile chlorinated hydrocarbon-contaminated tidal estuary
Authors: Hunt James , Birch Gavin , Warne Michael St. J. 
Published: March 2010

Abstract
Groundwater contaminated with volatile chlorinated hydrocarbons (VCHs) was identified as discharging to Penrhyn Estuary, an intertidal embayment of Botany Bay, New South Wales, Australia. A screening-level hazard assessment of surface water in Penrhyn Estuary identified an unacceptable hazard to marine organisms posed by VCHs. Given the limitations of hazard assessments, the present study conducted a higher-tier, quantitative probabilistic risk assessment using the joint probability curve (JPC) method that accounted for variability in exposure and toxicity profiles to quantify risk (δ). Risk was assessed for 24 scenarios, including four areas of the estuary based on three exposure scenarios (low tide, high tide, and both low and high tides) and two toxicity scenarios (chronic no-observed-effect concentrations [NOEC] and 50% effect concentrations [EC50]). Risk (δ) was greater at low tide than at high tide and varied throughout the tidal cycle. Spatial distributions of risk in the estuary were similar using both NOEC and EC50 data. The exposure scenario including data combined from both tides was considered the most accurate representation of the ecological risk in the estuary. When assessing risk using data across both tides, the greatest risk was identified in the Springvale tributary (δ = 25%)—closest to the source area—followed by the inner estuary (δ = 4%) and the Floodvale tributary (δ = 2%), with the lowest risk in the outer estuary (δ = 0.1%), farthest from the source area. Going from the screening level ecological risk assessment (ERA) to the probabilistic ERA changed the risk from unacceptable to acceptable in 50% of exposure scenarios in two of the four areas within the estuary. The probabilistic ERA provided a more realistic assessment of risk than the screening-level hazard assessment. Environ. Toxicol. Chem. 2010;29:1172–1181. © 2010 SETAC
Similarity, independence, or interaction for binary mixture effects of nerve toxicants for the nematode Caenorhabditis elegans
Authors: Svendsen Claus , Siang Pia , Lister Lindsay J. , Rice Annabel , Spurgeon David J. 
Published: March 2010

Abstract
Intensive agriculture can require the simultaneous use of more than one pesticide, resulting in the presence of mixtures in soils and waters. To assess mixture effects, concentration addition (CA) for similar acting chemicals and independent action (IA) for dissimilar acting chemicals are the most frequently used models. While the mechanistic basis for the selection of CA and IA for a given mixture appears appealing (similar vs dissimilar action), it has not yet been established how similar chemicals need to be in their effect before CA should be viewed as the most appropriate model. Here this is investigated in studies of the toxicity of binary mixtures of five different pesticides from three classes that have the same putative mode of action (neuroexcitation) but different molecular mechanisms in binary mixture tests with the nematode Caenorhabditis elegans. Effects of exposure on nematode survival were limited at the concentrations tested. Data analysis, therefore, focused on reproductive toxicity. Both CA and IA were found to be valid models for prediction of the toxicity of the 10 mixtures, although for seven CA provided a mathematically better fit. Both models could describe the toxicity for four mixtures; however, evidence for interaction was found in the remaining six cases. Where interactions occurred, these could be explained by information on the potential mechanisms of compound toxicokinetics—particularly when mixtures comprised a metabolically activated and a metabolically deactivated chemical and/or cases where the relative potencies of the two tested chemicals differed greatly. It is concluded, therefore, that detailed analysis of toxicokinetics and toxicodynamics can aid further understanding of interactions in mixtures. Environ. Toxicol. Chem. 2010;29:1182–1191. © 2010 SETAC
Chronic toxicity of fluorotelomer acids to Daphnia magna and Chironomus dilutus
Authors: Phillips Michelle M. , Dinglasan-Panlilio Mary J.A. , Mabury Scott A. , Solomon Keith R. , Sibley Paul K. 
Published: March 2010

Abstract
Saturated and unsaturated fluorotelomer carboxylic acids (fluorotelomer acids: FTAs) represent important intermediates in the degradation of fluorotelomer alcohols to perfluorinated carboxylic acids (PFCAs). Recent studies have detected FTAs at low concentrations (ng/L) in precipitation and surface waters; however, information regarding chronic toxicity is lacking. The present study assessed the chronic toxicity of the 8:2 saturated fluorotelomer carboxylic acid (8:2 FTCA) to Chironomus dilutus and the 10:2 saturated and unsaturated fluorotelomer carboxylic acids (10:2 FTCA and 10:2 fluorotelomer unsaturated carboxylic acid [FTuCA]) to Daphnia magna in separate life-cycle tests. In D. magna tests the FTCA was consistently more toxic than the FTuCA. Lethal concentrations (LC50s) were 150 and &gt;60 µg/L for FTuCA and FTCA, respectively. Reproduction was significantly reduced relative to the controls, with respective median effective concentrations (EC50s) for time to first brood and mean number of offspring/female of 287 and 214 µg/L for FTuCA and 50 and 48 µg/L for FTCA. In tests with C. dilutus, EC50s for survival and growth at 20 d were 2,610 and 1,250 µg/L. Total emergence and time to first emergence, the most sensitive endpoints, yielded EC50s of 440 and 890 µg/L. Few adults emerged and no reproduction occurred at the two highest concentrations (600 and 1540 µg/L). Mean number of eggs/female was not affected. These results represent the first chronic toxicity data for FTCAs and additional evidence that FTCAs are more toxic than some PFCAs. While the results indicate that current environmental concentrations of FTAs likely pose negligible risk to aquatic biota, additional quantification of FTAs in surface waters and assessment of their toxicity is needed before meaningful assessments of potential risks to aquatic biota are possible. Environ. Toxicol. Chem. 2010;29:1123–1131. © 2010 SETAC
Heavy metals, hematology, plasma chemistry, and parasites in adult hellbenders (Cryptobranchus alleganiensis)
Authors: Huang Chuan-Chin , Xu Yi , Briggler Jeffery T. , McKee Mike , Nam Paul , Huang Yue-wern 
Published: March 2010

Abstract
Ozark (Cryptobranchus alleganiensis bishopi) and eastern hellbenders (C. a. alleganiensis) from seven rivers in Missouri, USA, were collected to investigate essential information on hematology, parasites, and plasma chemistry and levels of select heavy metals (Hg, Pb, Cd, Cr, and Co) in the animals&apos; blood. The body masses of Ozark hellbenders were much smaller than those of eastern hellbenders. Blood parasites were detected in Ozark hellbenders, but not eastern hellbenders. The higher frequency in occurrence of eosinophils in Ozark hellbenders (8.8–16.8%) than in eastern hellbenders (highest at 6.6%) might result from the infection of parasites. Seven of the 18 hematology and plasma parameters (hematocrit, basophils, eosinophils, K, P, Ca, and chloride) showed significant differences between subspecies. The blood levels of heavy metals Co, Hg, and Pb differed significantly between subspecies. Ozark hellbenders had higher blood levels of Co (p &lt; 0.001), while blood levels of Hg and Pb were higher in eastern hellbenders. The levels of chromium (Cr) and cadmium (Cd) were not different between subspecies and among rivers. The eastern hellbenders at Niangua River and the Ozark hellbenders at the North Fork of the White River had lower Hg levels compared to eastern and Ozark hellbenders at other sites. All together, our findings provide important baseline information for managing this endangered species. Environ. Toxicol. Chem. 2010;29:1132–1137. © 2010 SETAC
Perinatal exposure to bisphenol-A changes N-methyl-D-aspartate receptor expression in the hippocampus of male rat offspring
Authors: Xu Xiao-Hong , Wang Ya-Min , Zhang Jing , Luo Qing-Qing , Ye Yin-Ping , Ruan Qin 
Published: March 2010

Abstract
Bisphenol-A (BPA) is one of the most common environmental endocrine disrupters with mixed estrogen agonist/antagonist properties. The toxicity of BPA has been extensively evaluated in a variety of tests in rodents, including developmental and reproductive toxicity, and carcinogenicity. The objective of the present study is to evaluate whether or not perinatal maternal exposure to BPA at 0.05, 0.5, 5, 50, and 200 mg/kg/d affects N-methyl-D-aspartate (NMDA) receptor (NMDAR) subunits NR1, NR2A, 2B, estrogen receptor beta (ERβ), and aromatase cytochrome P450 (P450arom) protein expressions of hippocampus in male rat offspring during postnatal development. Western-blotting analyses showed that perinatal exposure to BPA significantly affected the expression of NMDAR subunits. At the lower doses of 0.05 to 50 mg/kg/d, BPA concentration dependently inhibited the expression of NMDAR subunits. However, at the higher dose (200 mg/kg/d), the effects of BPA on these subunits were different, with a stronger inhibition of NR1 expression and a slighter inhibition of NR2A, 2B expression when compared with those at the lower dosage of BPA. In addition, perinatal exposure to BPA inhibited the expression of ERβ protein, but increased P450arom protein expression in a concentration-dependent manner, especially during the early postnatal period (the first 1–3 postnatal weeks). No significant influence of BPA on P450arom was observed at postnatal week 8. These data suggest that environmental BPA exposure may affect the development of the brain, enhancing the local biosynthesis of estrogen in the brain, inhibiting ERβ and NMDAR expressions. Environ. Toxicol. Chem. 2010;29:176–181. © 2009 SETAC
Comparing methods for analyzing overdispersed count data in aquatic toxicology
Authors: Noe Douglas A. , Bailer A. John , Noble Robert B. 
Published: March 2010

Abstract
Endpoints in aquatic toxicity tests can be measured using a variety of measurement scales including dichotomous (survival), continuous (growth) and count (number of young). A distribution is assumed for an endpoint and analyses proceed accordingly. In certain situations, the assumed distribution may be incorrect and this may lead to incorrect statistical inference. The present study considers the analysis of count effects, here motivated by the Ceriodaphnia dubia reproduction study. While the Poisson probability model is a common starting point, this distribution assumes that the mean and variance are the same. This will not be the case if there is some extraneous source of variability in the system, and in this case, the variability may exceed the mean. A computer simulation study was used to examine the impact of overdispersion or outliers on the analysis of count data. Methods that assumed Poisson or negative binomially distributed outcomes were compared to methods that accommodated this potential overdispersion using quasi-likelihood (QL) or generalized linear mixed models (GLMM). If the data were truly Poisson, the adjusted methods still performed at nominal type I error rates. In the cases of overdispersed counts, the Poisson assumed methods resulted in rejection rates that exceeded nominal levels and standard errors for regression coefficients that were too narrow. The negative binomial methods worked best in the case when the data were, in fact, negative binomial but did not maintain nominal characteristics in other situations. In general, the QL and GLMM methods performed reasonably based on the present study, although all procedures suffered some impact in the presence of potential outliers. In particular, the QL is arguably preferred because it makes fewer assumptions than the GLMM and performed well over the range of conditions considered. Environ. Toxicol. Chem. 2010;29:212–219. © 2009 SETAC
Chronic, dietary polybrominated diphenyl ether exposure affects survival, growth, and development of Rana pipiens tadpoles
Authors: Cary Coyle Tawnya L. , Karasov William H. 
Published: March 2010

Abstract
Levels of polybrominated diphenyl ethers (PBDEs) in the environment have been increasing rapidly over the past two decades; however, the toxicology of these compounds to aquatic organisms is poorly understood. Because amphibians play a role in both aquatic and terrestrial food webs, and are currently undergoing worldwide population declines, it is of interest to determine how PBDEs may affect amphibian health. This is the first study that reports chronic, dietary effects of environmentally relevant levels (7–277 ng/g wet food) of PBDEs in amphibians throughout larval development. Beginning at the free-swimming stage (Gosner Stage [GS] 25), Rana pipiens tadpoles were orally exposed to a technical pentabromodiphenyl ether mixture (DE-71) through metamorphic climax (GS 42). On exposure day 43, a subset of tadpoles was removed for body residue analysis. Sum PBDEs in whole-body tissue correlated linearly to dietary concentrations with BDE-99 represented as the highest contributing congener in both diet and tissue. Survival among all treatments compared to the control was decreased by DE-71 exposure. Further, growth and development were delayed in all but the highest treatment, perhaps indicating greater PBDE tolerance among those individuals that survived the highest treatment. Time to metamorphic climax was delayed, on average, 22 to 36 d in DE-71-treated tadpoles compared to control tadpoles. Additionally, size at metamorphosis was smaller in the highest treatment, suggesting that individuals that survived and metamorphosed similarly to the controls did so with a trade-off in size. At environmentally relevant levels, PBDEs induced mortality as well as sublethal effects on developing tadpoles through dietary exposure. Environ. Toxicol. Chem. 2010;29:133–141. © 2009 SETAC