bluuebunny/crossref_metadata_2025_split huggingface dataset:
Terrestrial wildlife exposed to agrochemicals: An ecological risk assessment perspective
Authors: Kendall Ronald J. , Akerman J. 
Published: March 2010

Abstract
Ecological risk assessment of wildlife exposed to agrochemicals addresses hazard and exposure to at least qualify and attempt to quantify the ecological risk. To accomplish a present-day ecological risk assessment in wildlife toxicology, data must be available from several disciplines: annlytical toxicology/environmental chemistry, biochemical toxicology, and wildlife ecology/ecotoxicology. This interdisciplinary approach, essential in wildlife toxicology for the assessment of the chemical effects on the reproduction, health, and well-being of wildlife, makes it difficult to rapidly generate the data necessary for ecological risk assessments. However, as the field has evoloed, it has become clear that interdisciplinary cooperation is critical to provide the complex data sets required for the registration and reregistration of pesticide products by the U.S. Environmental Protection Agency. The science of ecological risk assessment for terrestrial wildlife exposed to agrochemicals advanced rapidly during the decade of the 1980s and into the 1990s. The ecological risk assessment process will continue to improve as a result of improved data sets available for conduct of such assessments. Addressing the ecological risks associated with the use of an agricultural chemical involves a complex array of laboratory and field studies, in essence, a research program.
The role of models in ecological risk assessment: A 1990's perspective
Authors: Barnthouse Lawrence W. 
Published: March 2010

Abstract
Previously published reviews of mathematical models available for ecological risk assessment have emphasized population and ecosystem modeling approaches originally developed 20 years ago or more. Discussions of applications have focused on quantifying ecological effects of toxic chemicals and pesticides. This review emphasizes (a) modeling approaches developed within the last decade; (b) applications to a broad array of environmental problems on local, regional, and global scales; and (c) the relevance of different types of models to different components of the risk assessment process.
Biological and abiotic losses of polynuclear aromatic hydrocarbons (PAHs) from soils freshly amended with sewage sludge
Authors: Wild S.R. , Jones K.C. 
Published: March 2010

Abstract
Sewage sludge containing typical indigenous concentrations of polynuclear aromatic hydrocarbons (PAHs) was applied to several different soils in glass microcosms. Biologically active and sterilized soils were monitored for PAH content over a period of approximately 205 d. Agricultural soils with and without previous exposure to sewage sludge were tested, together with a forest soil and a soil from a major roadside. Loss of PAHs from a soil spiked with a PAH standard solution was also investigated. Results indicate the PAH compounds with less than four benzene rings are susceptible to abiotic loss processes. However, losses by these mechanisms were insignificant for compounds with four or more benzene rings. Half-lives for the sludge-applied PAHs were derived and indicated a strong dependence of persistence on chemical structure. Half-lives for phenanthrene and benzo[gle]perylene were between 83 and 193 d and 282 and 535 d, respectively. Mean half-lives correlate directly with log Kow and inversely with log water solubility. Behavior of PAHs was different in each soil, probably due to different soil characteristics and history of PAH exposure. The soil spiked with PAHs provided the lowest half-life values for most PAH compounds, suggesting a higher susceptibility of spiked PAHs to both abiotic and biological degradation.
Pesticide concentration patterns in agricultural drainage networks in the lake Erie Basin
Authors: Richards R. Peter , Baker David B. 
Published: March 2010

Abstract
This paper presents information on pesticide concentrations in Lake Erie tributaries draining agricultural watersheds, information distilled from data sets spanning nearly a decade and including up to 750 samples per tributary. Pesticide concentrations are strongly skewed and approximately lognormal. Average concentrations in tributaries are correlated with the amount applied in the basin, but with important secondary effects from chemical properties and modes of application of the pesticides. During runoff of storm events following application, concentrations rise rapidly, peak about the time of peak discharge, and decline slowly thereafter. These patterns do not match those for nutrients, major ions, or sediment, indicating a different pathway from the fields for pesticides. On an annual basis, elevated monthly average concentrations are usually observed from May to August, and low concentrations are present during the rest of the year. Monthly average concentrations of atrazine and alachlor generally exceed maximum contaminant levels (MCLs) in at least one month following application, but those of other herbicides do not. Annual averages are below MCLs for all compounds. No long-term trends are apparent. Comparisons of patterns in large and small tributaries show that small tributaries have higher maximum concentrations, more frequent concentrations below detection limit, and fewer intermediate concentrations. Smaller tributaries have more strongly skewed distributions and much greater temporal variability in concentrations than do larger rivers.
The aqueous photolysis of triclopyr
Authors: Woodburn Kent B. , Batzer Fred R. , White Frank H. , Schultz Mark R. 
Published: March 2010

Abstract
The aqueous photolysis of triclopyr was examined in both pH 7-buffered water and natural river water under artificial lights and midsummer sunlight (40°N latitude). The pseudo-first-order half-lives in pH 7-buffered water and natural river water averaged 0.5 and 1.3 d, respectively, at 25°C. Diffuse mercury lamps and midsummer sunlight produced similar rates of triclopyr decay and photoproduct distribution for a given solution. The photolysis of untreated river water produced a significantly different distribution of photoproducts compared to sterile, pH 7-buffered water. The photolysis of triclopyr in river water generated oxamic acid as the major photoproduct and a number of other low-molecular-weight carboxylic acids as minor products. Photolysis in sterile, pH 7-buffered water produced 5-chloro-3,6-dihydroxy-2-pyridinyloxyacetic acid as the major photoproduct, with minor amounts of oxamic acid and other low-molecular-weight acids.
Bioaccumulation of organic and inorganic selenium in a laboratory food chain
Authors: Besser John M. , Canfield Timothy J. , La Point Thomas W. 
Published: March 2010

Abstract
Aquatic organisms accumulated selenium (Se) from inorganic and organic Se species via aqueous and food-chain exposure routes. We measured aqueous and food-chain Se bioaccumulation from selenate, selenite, and seleno-L-methionine in a laboratory food chain of algae (Chlamydomonas reinhardtii), daphnids (Daphnia magna), and fish (bluegill, Lepomis macrochirus). Selenium concentrations were monitored radiometrically with 75Se-labeled compounds. All three organisms concentrated Se more strongly from aqueous selenomethionine than from either inorganic Se species. Bioconcentration factors (BCFs) estimated from 1 μg Se/L Se-methionine exposures were approximately 16,000 for algae, 200,000 for daphnids, and 5,000 for bluegills. Algae and daphnids concentrated Se more strongly from selenite (BCFs = 220–3,600) than selenate (BCFs = 65–500) whereas bluegills concenrated Se about equally from both inorganic species (estimated BCFs = 13 to 106). Bioaccumulation of foodborne Se by daphnids and bluegills was similar in food chains dosed with different Se species. Daphnids and bluegills did not accumulate Se concentrations greater than those in their diet, except at very low dietary Se concentrations. Food-chain concentration factors (CFs) for daphnids decreased from near 1.0 to 0.5 with increases in algal Se concentrations, whereas CFs estimated from bluegill exposures averaged 0.5 over a range of foodborne Se concentrations. In exposures based on selenite, bluegills accumulated greater Se concentrations from food than from water. Aqueous and food-chain Se uptakes were approximately additive, and depuration rates were similar in aqueous, food-chain, and combined exposures. Our results suggest that bluegills in Secontaminated habitats accumulate inorganic Se species primarily via food-chain uptake, although organoselenium compounds such as Se-methionine may contribute significantly to Se bioaccumulation by bluegills via both aqueous and food-chain uptake.
The effect of ivermectin on the invertebrate fauna associated with cow dung
Authors: McCracken D.I. , Foster G.N. 
Published: March 2010

Abstract
On each of four dates between May and September 1988, ivermectin was mixed into 60 × 1 kg pats of cattle dung, such that each contained 2, 1, 0.5, or 0 mg ivermectin per kilogram. The pats were then placed on pasture in a stratified, random, block plot and exposed for 15, 30, 45, 60, or 90 d. Twelve pats and a soil sample from below each were lifted at the end of these exposure periods and invertebrates extracted from both dung and soil. This study concentrated on the differences between experimental pats with regard to the numbers and types of Diptera and Coleoptera present. A total of 65 taxa were identified, and the data sets obtained for the dung and the soil were analyzed separately, using two multivariate techniques—TWINSPAN and DECORANA. The major factors determining the fauna of the dung pats and of the soil below them were found to be length of exposure on pasture, exposure date, and ivermectin presence/absence. The presence of ivermectin in the dung markedly changed the fauna in and below treated pats, particularly affecting cyclorrhaphan fly larvae. It is suggested that the incorporated multivariate methods have great potential for use in environmental contamination studies, as they analyze complex data sets objectively and allow the identification of faunal characteristics of treated and untreated sites.
Statistical analysis of theCeriodaphniatoxicity test: Sample size determination for reproductive effects
Authors: Oris James T. , Bailer A. John 
Published: March 2010

AbstractAn analysis of sample size requirements for the Ceriodaphnia dubia reproduction toxicity test is presented. Sample size requirements for detecting nominally specified biological effect sizes in the presence of different variance models are examined over a range of false positive error rates (α) and false negative error rates (β). Mean total young produced per female from control organisms in 53 separate toxicity tests yields a mean (22.52) and variance (68.25) that are used in sample size determinations. Results from these calculations demonstrate that in tests using the currently accepted sample size of 10 organisms per concentration, hypothesis-testing techniques are capable of detecting a range of 31 to 100% reproductive inhibition relative to controls. This wide range of minimum detectable inhibition values indicates that the ability to detect biologically significant levels of reproductive inhibition in this test is constrained by the statistical properties (i.e., power) associated with the currently accepted test protocol. It is suggested that the design of the Ceriodaphnia toxicity test be based not only on a minimum level of control reproductive output (as currently recommended), but also on the ability to detect a specified level of reproductive inhibition.
Bioavailability of fluoranthene in freshwater sediment toxicity tests
Authors: Suedel Burton C. , Rodgers John H. , Clifford Philip A. 
Published: March 2010

Abstract
To examine equilibrium-partitioning model predictions of interstitial water concentrations of fluoranthene as part of the equilibrium-partitioning (EqP) approach to sediment quality criteria development, the bioavailability (toxicity) of fluoranthene-amended sediment (a nonpolar organic compound) to Hyalella azteca, Daphnia magna, and Chironomus tentans was determined. Fluoranthene was added to three freshwater sediments with similar organic carbon content (0.44-0.50%). Although sediments were from divergent sources (Water Research Field Station [WRFS], Trinity River [TR], and Lake Fork [LF]), sediment physical and chemical characteristics did not vary appreciably, leading us to hypothesize (based on EqP theory) that fluoranthene-amended sediment toxicity would not vary between sediments. Predicted interstitial water concentrations from the equilibrium-partitioning model were similar to measured interstitial water concentrations for WRFS and TR sediment, but the model underpredicted measured values for LF sediment by a factor of two. EC50s for Daphnia magna, Hyalella azteca, and Chironomus tentans in interstitial water were a factor of two to five greater for LF than for WRFS and TR sediments. Factors other than organic carbon content of sediments (e.g., dissolved organic carbon content in interstitial water) probably contributed to the variability in bioavailability of fluoranthene. Based on 10-d sediment toxicity tests with Hyalella azteca, Daphnia magna, and Chironomus tentans, organic carbon-normalized sediment concentrations were better predictors of toxicity than interstitial water and bulk sediment fluoranthene concentrations. In 10-d aqueous-phase tests with fluoranthene, Chironomus tentans and Hyalella azteca were twice as sensitive as Daphnia magna. The response of freshwater organisms to fluoranthene-amended sediment was similar to that of marine organisms exposed to fluoranthene in other studies. The EqP approach for sediment-quality criteria accurately predicted sediment toxicity for WRFS and TR sediments but not for LF sediment, indicating the model may be overly protective for some bottom sediments. Factors other than organic carbon content may be important in affecting neutral organic compound bioavailability.
Comparative uptake kinetics and transport of cadmium and phosphate in Phleum pratense-Glomus deserticolum associations
Authors: Arnold Paul T. , Kapustka Lawrence A. 
Published: March 2010

Abstract
Mycorrhizal plants (timothy grass, Phleum pratense with Glomus deserticolum) were compared to nonmycorrhizal timothy grass to determine the effect of the mycorrhizal condition on the uptake and transport of cadmium. Companion experiments were conducted to ascertain phosphate uptake kinetics of mycorrhizal and nonmycorrhizal plants. Divalent cation competition experiments also were employed in this study. Comparisons of the high-affinity uptake mechanisms between mycorrhizal and nonmycorrhizal plants identified higher levels of phosphate uptake were due to an increase in the number of uptake sites rather than to differences in affinity. The respective values for Km for high-affinity phosphate uptake were 2.5 ± 1.3 μM P (mycorrhizal) and 3.4 ± 1.3 μM P (non-mycorrhizal), but these values were not statistically different at the α = 0.05 level. High-affinity Cd2+ uptake differed significantly between mycorrhizal (4.5 ± 2.8 μM) and nonmycorrhizal (2.8 ± 1.1 μM) plants. Presence of Ca2+ at 1.0 mM concentration conferred considerable competitive protection in both the mycorrhizal and the nonmycorrhizal conditions. The effect of Ca2+ was an approximate fourfold increase in the respective Km values.
Alternatives for the no-observed-effect level
Authors: Hoekstra J.A. , van Ewijk P.H. 
Published: March 2010

Abstract
This paper questions the usefulness of the no-observed-effect level (NOEL) as a summary statistic for ecotoxicological experiments. Quantification of the NOEL depends critically on size and variability of an experiment: smaller and less precise experiments lead to higher values for the NOEL, which gives the wrong signal to suppliers of a NOEL. The NOEL will generally lie in a dose range where possible effects cannot be excluded, even within the context of the experiment. Hence it does not form a suitable starting point for extrapolation to field situations. Alternative methods of finding a dose with a negligible effect are discussed. A two-step procedure is proposed that involves finding the dose whose effect is at most 25%, followed by linear extrapolation to a dose whose effect is acceptably small. The procedure leads to higher values if efforts are made to increase the power of the experiment.
Application of the computer-automated structure evaluation (CASE) program to the study of structure-biodegradation relationships of miscellaneous chemicals
Authors: Klopman Gilles , Balthasar D. M. , Rosenkranz H. S. 
Published: March 2010

AbstractThe computer-automated structure evaluation (CASE) methodology has been used to investigate the correlation between chemical structure and rate of biodegradation. A training set consisting of 283 diverse organic chemicals of known biodegradation activity was evaluated. Computer-automated structure evaluation identified six major activating fragments that contained oxygen in a carbonyl or hydroxyl group, suggesting that the presence of oxygen plays a significant role in biodegradation. The training set predicts the biodegradation categories correctly 74% of the time for an independent validation set of 27 chemicals. By also using a data base of diverse chemicals whose activity was based on acclimated inocula, two prediction results were obtained for each of the 27 chemicals of an independent validation set. Analysis of the results showed that the chemicals could be grouped into five prediction categories. Two of these categories included chemicals for which both data bases predicted exactly the same activity, whereas a third category contained two chemicals for which no conclusion was made. The other two categories include chemicals of intermediate activity, that is, chemicals that can undergo slow or fast biodegradation, depending on the conditions. In addition, the identification of activating structural fragments has provided information on mechanisms for biodegradation in the environment.
Lead and cadmium accumulation in eggs and fledgling seabirds in the New York bight
Authors: Burger Joanna , Gochfeld Michael 
Published: March 2010

Abstract
We measured lead and cadmium concentrations in eggs and in the breast feathers of fledglings of common tern (Sterna hirundo), roseate tern (S. dougallii), Forster's tern (S. forsteri), black skimmer (Rynchops niger), and herring gull (Larus argentatus) nesting in mixed-species colonies in the New York Bight in 1989. Metal concentrations in fledgling feathers represent in part metals sequestered in the egg by females and accumulation from food brought back to chicks by parents, and thus may be a measure of local metal acquisition. There were significant interspecific differences in lead in eggs, and lead and cadmium in fledgling feathers. Herring gulls had the most lead in eggs (up to means of 6,740 ng/g, dry weight), whereas the terns had the least (mean of 318 ng/g, dry weight). Cadmium concentrations were generally low in all examined eggs (&lt;22 ng/g, dry weight). Lead concentrations were high in fledgling feathers (up to 4,090 ng/g, dry weight) in some populations of all species. Cadmium was highest in fledgling feathers of herring gull and skimmers. Among fledgling terns, the roseate tern (a federally endangered species) had the highest concentrations. For all species except herring gull, the feathers of fledglings had higher levels of metals than did eggs.
Aqatic toxicity equivalency factors for chlorinated phenolic compounds present in pulp mill effluents
Authors: Kovacs T. G. , Martel P. H. , Voss R. H. , Wrist P. E. , Willes R. F. 
Published: March 2010

AbstractAquatic toxicity equivalency factors (TEFs) for chlorinated phenolic compounds present in blached kraft mill effluents were estimated using published chronic toxicity data for fathead minnows, rainbow trout, zebra fish, American flagfish, and sea urchins. To provide the most consistent and reliable approach for estimating relative toxicity, each set of toxicity data employed for TEF determination encompassed only data relating to a common toxic end point, a single aquatic test species, and a common method of testing and of statistical analysis. The TEF values were determined as a ratio of the chronic threshold values for the mono-to pentachloro-substituted phenolics to that for pentachlorophenol, where the threshold values were obtained from linear regression equations relating chronic toxicity to the number of chlorine substituents for a given chlorinated phenolic. Using this approach, the TEF values for monochloro-, dichloro-, trichloro-, tetrachloro-, and pentachloro-substituted phenolic compounds were determined to be 0.04, 0.1, 0.2, 0.5, and 1.0, respectively.
Identification of methyl parathion toxicity in colusa basin drain water
Authors: Finlayson B. J. , Harrington J. A. , Fujimura R. , Isaac G. 
Published: March 2010

Abstract
The cause of toxicity to young striped bass Morone saxatilis and mysids Neomysis mercedis from an agricultural drain (Colusa Basin Drain, Sacramento River Valley, CA) containing tail water from rice fields was investigated. Previous studies had postulated that toxicity was due to one or more of the insecticides carbofuran, malathion, and methyl parathion used on rice in California. The discharge of insecticide-tainted agricultural drain water into the Sacramento River may have contributed to the decline of the striped bass population in the Sacramento-San Joaquin Estuary, either directly by mortality or indirectly by reducing food items such as mysids. Trace metals cadmium, copper, and zinc from abandoned mining operations may also have contributed toxicity. Water samples were collected from the Colusa Basin Drain and upstream and downstream from the Sacramento River, analyzed for insecticides and trace metals, and tested for toxicity. No significant toxicity to striped bass was observed for either water body, and no significant toxicity to Neomysis mercedis was observed for the Sacramento River sites. However, Colusa Basin Drain water was significantly toxic to Neomysis mercedis, which was attributed to lethal (up to three times the 96-h LC50 value) concentrations of methyl parathion. The trace metals, carbofuran, and malathion were present at less than acutely toxic concentrations. The addition of 2 ppt salinity appeared to increase survival of both test organisms. This study clearly demonstrates the need for reducing environmental levels of methyl parathion.
Measurement of tributyltin contamination of sediments and Crassostrea virginica in the southern chesapeake bay
Authors: Espourteille Francois A. , Greaves John , Huggett Robert J. 
Published: March 2010

Abstract
Tributyltin concentrations in sediments and American oysters, Crassostrea virginica, from the southern Chesapeake Bay have been determined. Concentrations in both sediments and oysters were correlated with commercial shipping and recreational boating activity. Sediment concentrations as high as 4,000 μg kg−1 dry weight were observed in a marina. Detection limits in sediment were 1 to 14 μg kg−1, depending on sediment type. Tributyltin was found in all Crassostrea virginica, including [those from] locations where the compound could not be detected in sediment. Concentrations in Crassostrea virginica ranged from &lt; 10 μg kg−1 dry weight on the Atlantic Coast of Virginia to 5,600 μg kg−1 in the Elizabeth River, Virginia.