bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of coal pile leachate on Taylor Brook in western Massachusetts
Authors: Tan Barrie , Coler Robert A. 
Published: March 2010

Abstract
The metals in Taylor Brook, a second-order stream that receives the runoff and leachate from a coal pile, were analyzed and evaluated for toxicity. Al, Fe and Mn levels were highest immediately downstream from the coal pile at site 4, where the pH was 4.9. The water at this site was soft (41 ppm). Ca and Mg were predominantly unbound, yet maximum binding with organic acids occurred. The increase in SO4 concentrations (fourfold) and HCO3:SO4 ratios indicated little or no buffer capacity but the SO4:NO3:Cl ratios showed that the effect was local rather than a consequence of acid precipitation alone. The 96-h LC50 values for guppies in water from sites 4 and 3 were 26 and 100%, respectively. The increase of Al (80-fold) was inversely proportional to pH, but this proportionality was more pronounced at site 4 than at site 3. The 36-h LC50 values obtained on the addition of Al and acidity to water from site 3 at the levels measured in water from site 4 were 24% and greater than 100%, respectively. When compared with the values (17% and 49%) derived for site 4 water, the data indicate that the toxicity was principally exerted by aluminum. Residual oxygen data also suggest that fish mortality was primarily a function of Al. Additions of Al (0.3 ppm) to Taylor Brook control site water resulted in increased toxicity to guppies, while added acidity (pH 4.5) had no marked effect.
Acute and chronic effects of water quality criteria-based metal mixtures on three aquatic species
Authors: Spehar Robert L. , Fiandt James T. 
Published: March 2010

Abstract
Acute and chronic toxicity tests were conducted with three aquatic species to determine the effects of metals combined as mixtures at proposed water quality criteria concentrations and at multiples of the LC50 and maximum acceptable toxicant concentration (MATC) obtained from tests on six metals. These studies were the first part of a larger research effort to derive water quality criteria for combined pollutants by the U.S. Environmental Protection Agency.
Arsenic, cadmium, chromium, copper, mercury and lead combined at criterion maximum concentrations caused nearly 100% mortality in rainbow trout and daphnids (Ceriodaphnia dubia) during acute exposures. Fathead minnows were not adversely affected at this or two times this concentration, although a mixture of four to eight times the maximum value caused 15 to 60% mortality. Metals combined at the criterion average concentrations significantly reduced production of daphnid young and growth of fathead minnows after 7 and 32 d, respectively. Embryo hatchability and survival of rainbow trout were reduced at four times this criterion but not at the criterion average concentration.
Acute tests with metals mixed at multiples of the LC50 indicated that the joint action of the metals was more than additive for fathead minnows and nearly strictly additive for daphnids, based on toxic units calculated from the individual components of the mixture. Chronic tests showed that the joint action was less than additive for fathead minnows but nearly strictly additive for daphnids, indicating that long-term metal interactions may be different in fish than in lower invertebrates. Adverse effects were observed at mixture concentrations of one-half to one-third the MATC for fathead minnows and daphnids, respectively, suggesting that components of mixtures at or below no effect concentrations may contribute significantly to the toxicity of a mixture on a chronic basis. These results point out the need for additional studies to determine the type and degree of interaction of toxicants because single-chemical water quality criteria may not sufficiently protect some species when other toxicants are also present.
Survival of daphnia magna and hyalella azteca in cadmium-spiked water and sediment
Authors: Nebeker Alan V. , Onjukka Samuel T. , Cairns Michael A. , Krawczyk Daniel F. 
Published: March 2010

Abstract
Freshwater sediments and water were spiked with cadmium in the laboratory, and toxicity tests were conducted with the cladoceran Daphnia magna and the amphipod Hyalella azteca to determine if Cd in the sediment would cause increased toxicity. The 48-h LC50 values for Daphnia in tests without sediment were 36, 33, 24 and 40 μg/L total Cd. Calculated free ion (Cd2+) LC50 values for the same tests were 28, 25, 18 and 31 μg/L. LC50 values (48-h) determined for total Cd (uncentrifuged water sample) in the sediment-containing beakers were 252, 69 and 122 μg/L for Daphnia. LC50 values for dissolved Cd (centrifuged 10,000 rpm) in the sediment-containing beakers were 61, 27 and 100 μg/L for Daphnia. Higher total Cd LC50 values indicate that Cd adsorbed to soluble organic material was not biologically available. The 96-h LC50 value in tests without sediment for Hyalella was 8 μg/L total Cd; two 10-d LC50 values were less than 2.8 and 6.0 μg/L. LC50 values (96-h) determined for Hyalella for total and dissolved Cd in tests with sediment were 74 and 6.6 μg/L, respectively; the 10-d LC50 for total Cd in tests with sediment was 80 μg/L. No significant mortality of Daphnia or Hyalella occurred in the flow-through tests in which sediment contained the same levels of Cd as in the static tests. Mortality was similar in beakers with and without Cd-spiked sediment, indicating that Cd in the sediment and adsorbed to organic materials was not available to cause increased mortality.
Sediment quality criteria from the sediment quality triad: An example
Authors: Chapman Peter M. 
Published: March 2010

Abstract
Broad-scale comparative data for sediment chemistry, sediment bioassays and bottom fish histopathology are used to derive quantitative site-specific sediment criteria for three representative chemical contaminants in Puget Sound, Washington. The criteria, in terms of concentrations at or below which biological effects have been shown to be minimal, are (dry weight sediment): lead, 50 μg/g (ppm); combustion polyaromatic hydrocarbons, 3.8 μg/g; total polychlorinated biphenyls, 0.1 μg/g.
Tracking river plumes with volatile halocarbon contaminants: The St. Clair river-lake St. Clair example
Authors: Kaiser Klaus L. E. , Comba Michael E. 
Published: March 2010

Abstract
The concentrations of seven widespread, volatile, halocarbon contaminants–tetrachloroethylene (C2Cl4), carbon tetrachloride (CCl4), 1,1,1-trichloroethane (C2H3Cl3), trichloroethylene (C2HCl3), chloroform (CHCl3), bromodichloromethane (CHBrCl2) and Freon 12 (CCl2F2)–were determined in the lower reaches of the St. Clair River and throughout Lake St. Clair. The results indicate large inputs of carbon tetrachloride and tetrachloroethylene and smaller loadings of chloroform, 1,1,1-trichloroethane and trichloroethylene from the St. Clair River, particularly the South Channel, Bassett Channel and Chenal Ecarte, to Lake St. Clair. In total, daily loadings of more than 100 kg are indicated, resulting in a lake burden of approximately 1,000 kg of these halocarbons.
The plumes of contaminated river water, particularly for carbon tetrachloride and tetrachloroethylene, extend approximately 15 km into the shallow, well-mixed lake. At that range, the halocarbon levels generally drop to near-background concentrations, suggesting significant removal of the waterborne contaminants through volatilization.
Biolog, biodeg, and fate/expos: New files on microbial degradation and toxicity as well as environmental fate/exposure of chemicals
Authors: Howard Philip H. , Hueber Amy E. , Mulesky Barbara C. , Crisman Jenny S. , Meylan William , Crosbie Erin , Gray D. Anthony , Sage Gloria W. , Howard Karen P. , Lamacchia Anthony , Boethling Robert , Troast Richard 
Published: March 2010

Abstract
The environmental fate/exposure data base (EFEDB) has been under development with U.S. Environmental Protection Agency support since 1979. It was initiated because of the difficulty of identifying environmental release, fate and exposure information using traditional literature searches. Two new components (BIOLOG and BIODEG), which contain microbial toxicity and biodegradation information, and an update of the overall EFEDB file are described. In addition, a chemical fate/exposure file (FATE/EXPOS) is discussed; it contains production and use data as well as physical-chemical properties, chemical fate data and monitoring information. EFEDB has been greatly expanded since its initial development, and considerable conversions are planned to make most of the files available through the Chemical Information System (CIS). A major goal of EFEDB was to provide a source of data for constructing structure-activity correlations and BIODEG is one of the first steps in providing evaluated data for such correlations. FATE/EXPOS provides sorting capabilities for setting priorities in testing or regulation based on easily obtainable information about exposure potential.
Combined and separate effects of cadmium, lead and zinc on ALA-D activity, growth and hemoglobin content indaphnia magna
Authors: Berglind Rune 
Published: March 2010

AbstractThe single and combined effects of cadmium, lead and zinc on δ-aminolevulinic acid dehydratase (ALA-D) activity, growth and hemoglobin content were studied in Daphnia magna. The ALA-D activity was enhanced by Cd and inhibited by Pb. The binary combinations, Pb:Cd and Pb:Zn, were powerful inhibitors of ALA-D. However, in the combination of the highest concentrations of lead and zinc the activity of ALA-D was enhanced. The stimulation by cadmium was abolished in the presence of zinc. All tertiary combinations of Pb, Cd and Zn inhibited ALA-D activity. Lead alone did not decrease the hemoglobin content in D. magna even at 260 μg/L Pb, but in combination with zinc the decrease was abolished. Tertiary combinations of Cd, Pb and Zn were not more powerful in affecting the hemoglobin content than were the binary combinations. Growth was not affected by Cd, Pb or Zn in any of the combinations used.
Comparison of short-and long-term sexual reproduction tests with the marine red alga champia parvula
Authors: Thursby Glen B. , Steele Richard L. 
Published: March 2010

Abstract
A 2-d exposure test using the marine red alga Champia parvula was developed to assess the toxic effects of pollutants entering the marine and estuarine environments. The initial exposure was followed by a 5- to 7-d recovery period to allow the development of any cystocarps (evidence of sexual reproduction, the endpoint measured). The 2-d exposure test was validated by comparison with a previously developed 2-weed tests in which “no sexual reproduction” was used as the reproductive endpoint. The 2-d procedure is intended for use in testing both single compounds and complex effluents. Complex effluents, however, cannot be accurately tested with the 2-week test; therefore, only single compounds were used to compare the two procedures. Nine single compounds were tested. Concentrations that resulted in a 95% or greater decrease from the control response with the 2-d exposure were considered the best estimate of the no sexual reproduction response from the 2-week test. All of the single compounds tested, except cadmium, yielded essentially the same results with both tests.
Physical and chemical factors that influence the anaerobic degradation of methyl parathion in sediment systems
Authors: Wolfe N. L. , Kitchens B. E. , Macalady D. L. , Grundl T. J. 
Published: March 2010

Abstract
The kinetics of disappearance of methyl parathion (0,0-dimethyl-0-p-nitrophenyl phosphorothioate) were studied in anaerobic sediment samples in the laboratory as a function of methyl parathion concentration, pH and Eh. The disappearance of methyl parathion is described by first-order kinetics and amino methyl parathion (0,0-dimethyl-0-p-aminophenyl phosphorothioate) was identified as a reduction product. In the strongly reducing sediments, the half-lives were on the order of a few minutes. In water isolated from the sediment, no reaction could be detected over the period of a week. Also, there is no apparent correlation between the first-order disappearance rate constants and the pH of the sediment samples. In heat-sterilized sediments, the disappearance rate constants are retarded about two orders of magnitude relative to nonsterile sediments. In chemically treated sediments, first-order disappearance rate constants are comparable to those in the nonsterile system.
Comparison of computer model predictions with unsaturated zone field data for aldicarb and aldoxycarb
Authors: Jones Russell L. , Black Gary W. , Estes Tammara L. 
Published: March 2010

Abstract
The ability of the Pesticide Root Zone Model (PRZM) to simulate the movement of aldicarb or aldoxycarb residues was evaluated using the soil properties and amounts of rainfall and irrigation measured in 34 unsaturated zone field study plots. Maximum leaching depth values obtained from the PRZM simulations agreed relatively well with those observed in the field experiments. Where irrigation water was applied in spatially nonuniform patterns to a field (as in furrow or flood irrigation), simulations show that the placement of the pesticide in relation to irrigation water must also be considered. The comparisons presented in this paper show that PRZM (if supplied with the proper degradation rates and appropriate soil, weather and agricultural parameters) can be used to assess movement of pesticides in agricultural environments. When used in conjunction with multiple year rainfall records, this model can be used to develop probability distributions of pesticide movement in the unsaturated zone. PRZM can also be linked to a ground water solute transport model to provide predictions of pesticide concentrations and transport in ground water. These techniques are useful in performing risk assessments and in developing potential management practices when needed.
Toxicological studies of benomyl and carbendazim in rainbow trout, channel catfish and bluegills
Authors: Palawski Donald U. , Knowles Charles O. 
Published: March 2010

Abstract
Benomyl and carbendazim exhibited high acute toxicity to channel catfish, Ictalurus punctatus (Rafinesque), but were much less toxic to rainbow trout, Salmo gairdneri (Richardson), and bluegills, Lepomis macrochirus (Rafinesque). Changes in water temperature, pH, and water hardness altered the acute toxicity to fish of both compounds; however, the alterations were less marked in channel catfish than in rainbow trout. Carbendazim injected intraperitoneally was not readily metabolized and was the major radioactive product excreted by the three fish species. The rapid depuration of radiocarbon into the containment water and the storage of residues in the gall bladder of each species indicated that both branchial and biliary excretion were major pathways for the elimination of carbendazim by fish. In the carbendazim residue dynamic studies, rainbow trout had the highest uptake rate constant and bioconcentration factor of the three species. Much less carbendazim was accumulated by channel catfish than by the other two species, but this residue level (0.44 μg/g) appeared to be lethal after 48 h of exposure. The elimination rate constant and biological half-life of carbendazim were similar for rainbow trout and bluegills; however, the elimination rate constant was larger and the biological half-life shorter in channel catfish than in the other two species. It was concluded that benomyl and carbendazim were selectively toxic to channel catfish compared with rainbow trout and bluegill, but because of the instability of benomyl and the fast elimination of carbendazim, the possibility of these compounds excessively bioconcentrating in fish was remote.
The relationship between aquatic toxicity QSARs and bioconcentration for some organic chemicals
Authors: Mccarty L. S. 
Published: March 2010

Abstract
Aquatic toxicity testing is conducted largely by means of a single experimental protocol-the concentration-response toxicity test. This procedure has a number of well-known limitations resulting from the fact that the relationship between the waterborne toxicant concentration and the actual body toxicant concentration which is producing the observed biological response is unknown. Hence quantifying the influence of chemical potency, physical, chemical and biological factors and elapsed time on the outcome of toxicity tests is difficult. Interpretation, and even more significantly, predictability may be severely restricted. Using, and further quantifying, the links between octanol-water partition coefficients, bioconcentration and acute and chronic toxicity quantitative structure-activity relationships (QSARs) for narcotic organic chemicals has allowed the following conclusions to be made: (1)Establishing internal toxicant concentrations related to acute and chronic effects, as estimated in this paper, will allow the toxicological significance of body burdens of certain organic chemicals, both singly and in certain mixtures, to be determined.(2)Chemical potency, as determined in the exposed organism, appears to be essentially constant for each of the biological responses and organic chemical groups examined.(3)The acute and chronic QSARs discussed herein are all parallel, each having a slope of unity.(4)It appears, as a first approximation, that a one-compartment, first-order kinetics model could provide a quantitative means of studying aquatic toxicity test results, both retrospectively and prospectively.(5)Bioconcentration and toxicity kinetics appear to be similar, but the internal toxicant concentration endpoint is different, fixed for toxicity and variable for bioconcentration.
Biodegradation data evaluation for structure/biodegradability relations
Authors: Howard Philip H. , Hueber Amy E. , Boethling Robert S. 
Published: March 2010

Abstract
Previous attempts at structure/biodegradability relations (SBRs) and available biodegradation data are reviewed and it is concluded that (1) not enough rate data on large numbers of chemicals are available to develop quantitative SBRs and (2) attempted qualitative SBRs have suffered from either poor documentation of the biodegradation evaluation or they have used limited biodegradation test data. Because of the poor reproducibility of biodegradation tests, a weight-of-evidence evaluation procedure is proposed. A system for collecting and evaluating biodegradation data from screening tests, biological treatment simulations, grab sample tests and field studies is described and study-specific and summary biodegradability codes in combination with reliability codes are developed that can be used for structure/biodegradability relations.
Reduction in bioavailability of organic contaminants to the amphipod pontoporeia hoyi by dissolved organic matter of sediment interstitial waters
Authors: Landrum Peter F. , Nihart Sheila R. , Eadie Brian J. , Herche Lynn R. 
Published: March 2010

Abstract
Dissolved organic matter (DOM) in aquatic systems is known to reduce the bioavailability of heavy metals. Recent studies have shown similar reductions in bioavailability of organic contaminants. The mechanism for reduction, with Aldrich humics, was to reduce the freely dissolved, bioavailable, xenobiotic concentration by partitioning to DOM. This mechanism was also found to apply to organic contaminants in the presence of DOM from interstitial waters. A reverse-phase separation technique was used to measure the sorbed xenobiotic, and by difference from the total, the freely dissolved concentration of a contaminant permitting the calculation of a partition coefficient (Krp). Equilibrium partitioning of selected polycyclic aromatic hydrocarbon and poly-chlorinated biphenyl congeners to the DOM, in interstitial waters from several geographical sources, ranged over several orders of magnitude for a single compound. The reduction in bioavailability was measured by reduction in the conditional uptake rate constant for organic xenobiotics in the presence of DOM, for the amphipod Pontoporeia hoyi (the major benthic invertebrate in the Great Lakes). Reduction in the conditional uptake rate constant versus controls was used to calculate a biologically determined partition coefficient (Kb). The log Krp was well correlated with log Kb, log Kb = 1.54(0.15) + 0.723(0.03) log Krp (r2 = 0.74, n = 195) over a range of three orders of magnitude in measured partition coefficient for individual compounds using DOM from different sources.
Uptake and excretion of zinc by several tissues of the lobster (Homarus Americanus)
Authors: Waiwood B. A. , Zitko V. , Haya K. , Burridge L. E. , Mcleese D. W. 
Published: March 2010

Abstract
Lobsters, Homarus americanus, were exposed in a flow-through system to a sublethal concentration of zinc (Zn++) for 4 d and then transferred to flowing unspiked sea water for 7 d. The concentrations (μg/g dry weight) of Zn++ after the four days of exposure were in the order gill &gt; green gland &gt; haemolymph &gt; hepatopancreas &gt; crusher tissue &gt; crusher muscle &gt; pincer tissue &gt; shell &gt; testes &gt; heart &gt; pincer muscle &gt; abdominal (tail) muscle. After 7 d in unspiked water the concentration of Zn++ in each of the tissues decreased, but did not return to pre-exposure levels. In terms of the total tissue burden the level of Zn++ in only the hepatopancreas continued to increase during the depuration phase. The data were analysed using a four-compartment model with haemolymph as the “central” compartment. The exchange of Zn++ between gills and water was rapid, between gills and haemolymph was somewhat slower, and between haemolymph and tail muscle was extremely slow.
Avoidance behavior of mallards and northern bobwhite exposed to carbofuran-contaminated food and water
Authors: Kononen D. W. , Hochstein J. R. , Ringer R. K. 
Published: March 2010

Abstract
Food and water avoidance experiments were conducted on mallards (Anas platyrhynchos L.) and northern bobwhite (Colinus virginianus L.) exposed to a range of dietary carbofuran concentrations. A dietary avoidance concentration 50 (analogous to an LC50) was calculated for each avoidance experiment. This statistic describes the dietary toxicant concentration threshold at which, when exceeded, exposed animals are likely to discriminate between untreated and treated feed or water. The food avoidance concentration 50s (FAC50s) for mallards and bobwhite were 10 and 159 ppm, respectively. The water avoidance concentration 50 (WAC50) for mallards was 3 ppm. For bobwhite the WAC50 for carbofuran was estimated to exceed 50 ppm.
In situ variations in oyster mutagenicity and tissue concentrations of polycyclic aromatic hydrocarbons
Authors: Pittinger Charles A. , Buikema Arthur L. , Falkinham Joseph O. 
Published: March 2010

Abstract
Variations in oyster mutagenicity were monitored in a series of in situ relocation experiments and compared with tissue concentrations of polycyclic aromatic hydrocarbons (PAHs). Oysters (Crassostrea virginica) were relocated among three rivers in the southern Chesapeake Bay and sampled over a 2-week exposure period. Extracts of oyster tissues were assayed for mutagenic activity by the Salmonella typhimurium microsomal test and analyzed for selected PAHs by gas chromatography. Oysters relocated to the polluted Elizabeth River (Norfolk, VA) from a pristine site (Ware River, VA) accumulated mutagenic activity and PAHs within 3 d following relocation. Mutagenicity increased over a 14-d period while tissue levels of most PAHs stabilized or declined after 3 d. Extracts of native oysters from the Elizabeth River exhibited comparable levels of mutagenic activity as 14-d relocated oysters. In elimination experiments, PAH levels and mutagenic activity of Elizabeth River oysters decreased following relocation to the Ware River and were not detected after 14 d. Regression analyses did not detect a significant association between slopes of mutagenicity dose-responses and tissue levels of PAHs. Marginal associations with numbers of Salmonella revertants per plate were detected in comparisons with sums of PAH tissue levels, and with tissue levels of benzofluoranthene.