bluuebunny/crossref_metadata_2025_split huggingface dataset:
An assessment of the ontario ministry of the environment protocols for conducting Daphnia magna acute lethal toxicity tests with pulp and paper mill effluents
Authors: Kovacs Tibor G. , Ferguson Scott M. 
Published: March 2010

Abstract
The Ontario Ministry of the Environment protocols for conducting Daphnia magna acute lethal toxicity tests were evaluated for pulp and paper mill effluents. The evaluation included an interlaboratory study and an intralaboratory assessment using different dilution waters, test containers and pH adjustment. When the tests were conducted under similar conditions, the results (i.e., 48-h LC50s) from four participating laboratories were similar. With one exception, the coefficients of variation for interlaboratory testing ranged from 3.0 to 17%. However, within a laboratory, the ratio of the highest to lowest LC50 values for a particular effluent ranged from 1.9 to 3.8 when using different dilution waters and ranged from 1.3 to 1.9 when the test solution pH was adjusted to the same level as the dilution water pH. The D. magna were found to be 1.5 to 4.0 times less sensitive than rainbow trout and 1.6 to 3.0 times less sensitive than Ceriodaphnia affinis to pulp and paper mill effluents, and dehydroabietic acid.
Predicting concentrations of consumer product chemicals in estuaries
Authors: Lung Wu-Seng , Franco Andres C. , Rapaport Robert A. 
Published: March 2010

Abstract
About 25 to 30% of all United States (U.S.) publicly owned treatment works (POTW) discharges enter estuaries and coastal waters. An expert system has been developed to model the fate and transport of chemicals discharged from POTWs into estuaries. Each POTW has been classified as one of four groups: primary, trickling filter, lagoon and activated sludge in terms of treatment level. The system is designed to calculate concentrations under 7-d 10-year low flow, summer low flow and annual mean flow conditions. To account for varying mixing characteristics and salinity distributions observed in a given estuary, the system includes one-dimensional and two-dimensional (longitudinal and vertical) mass transport algorithms. To date, the modeling framework has been applied to nine estuaries. For validation purposes, biochemical oxygen demand (BOD) concentrations are also predicted based on industrial as well as municipal organic carbon loads. In several estuaries, predicted in-stream BOD levels have been compared to measured BOD data resulting in successful model validation. The validated models are then used to predict linear alkylbenzene sulfonate (LAS) concentrations in estuaries. These LAS concentrations are found to be less than 20 μg/L in these estuaries under the three flow conditions.
Population-specific toxicity responses by the freshwater oligochaete, Stylodrilus heringianus, in natural lake michigan sediments
Authors: Keilty Timothy J. , Landrum Peter F. 
Published: March 2010

Abstract
Sediment reworking rate, mortality and organism dry weight were measured for Stylodrilus heringianus in laboratory microcosms. The experiments were designed to identify potential population-specific response differences to mixed (stirred to obtain a more uniform particle size distribution over depth) and unmixed (passively settled) microcosm sediments. Lake Michigan sediments and worms were collected offshore Benton Harbor, Michigan and Grand Haven, Michigan.
The mixed Benton Harbor sediments were toxic to S. heringianus collected from Grand Haven, whereas there were no significant differences in measured responses between mixed and unmixed sediment microcosms for Grand Haven-collected worms exposed to Grand Haven sediments or Benton Harbor-collected worms exposed to Benton Harbor sediments. Note that the mixing of sediments resulted in increased availability of contaminants sorbed to the fine sediment fraction.
Because contaminant and oligochaete population density data suggest that Grand Haven sediments are less contaminated, the population-specific response suggests that S. heringianus may adapt to the low level long-term stressful conditions (chemical or otherwise). Results also suggest caution and consideration of the history of test organisms in the design and interpretation of toxicity tests.
Chloroacetones in pulp mill chlorination-stage effluents
Authors: McKague A. B. , Bradley D. , Meier H. P. , Monteith D. , Betts J. L. 
Published: March 2010

Abstract
Ninety-six h LC50 values for 1,1,3-trichloro-, 1,1,3,3-tetrachloro-, pentachloro- and hexachloroacetone for juvenile rainbow trout (Salmo gairdneri) were 2.3, 11.0, 25.0 and &gt;25 mg/L, respectively. Levels in chlorination-stage effluents from eight pulp mills sampled across Canada were as follows: trichloro-, &lt;0.1 to 2.4; tetrachloro-, 0.4 to 6.9; pentachloro-, 0.1 to 7.5 and hexachloro-, &lt;0.1 to 0.6 mg/L. Combined levels ranged from 0.9 to 17.0 mg/L.
Protein-mediated selenium biomethylation in evaporation pond water
Authors: Thompson-Eagle E. T. , Frankenberger W. T. 
Published: March 2010

AbstractSelenium (Se) is a contaminant of agricultural drainage water in the San Joaquin Valley, California and the cause of major toxicity problems among the wildlife. The objective of this study was to investigate the stimulatory properties of proteins and their components with respect to biological Se dissipation. Laboratory studies showed that Se biomethylation is protein-peptidelimited rather than nitrogen-, amino acid- or carbon-limited. Crude casein and its components, ∂-, β-, and κ-caseins and peptides (1 g carbon [C] L−1 pond water) were equally stimulatory producing a &gt;50-fold enhancement in dimethylselenide (DMSe) yield. Dephosphorylation of casein resulted in a 57% reduction in Se volatilization. Dialysis studies indicated that the active ingredient of casein is likely to be a peptide or peptide mixture. Casein did not appear to increase Se methylation through any physicochemical characteristics such as a change in pH or chelation of pond water ions. Alternative protein sources including cottonseed meal, cheese whey and yeast sludge dramatically increased methylation (29-fold, 300-fold and 41-fold, respectively) over unamended samples, with over 10% of the Se inventory converted into DMSe in 17 d. A single casein amendment (0.2 g CL−1) to water columns in the field caused a 38% Se loss from the initial inventory of a San Joaquin Valley evaporation pond in 142 d. Under optimum conditions, protein-mediated deseleinfication of agricultural drainage water is a promising and novel bioremediation technique to permanently remove Se on site.
Effort-allocation analysis of the seven-day fathead minnow (Pimephales promelas) and Ceriodaphnia dubia toxicity tests
Authors: Kszos Lynn Adams , Stewart Arthur J. 
Published: March 2010

Abstract
Water quality-based limits are receiving greater emphasis in National Pollutant Discharge Elimination System permits. These permits often contain requirements for conducting acute or chronic toxicity tests of wastewater and/or ambient receiving waters. In this paper, we analyze the effort (in person-hours per test-ph/t) required to conduct the 7-d fathead minnow (Pimephales pro-melas) larval survival and growth test, the 7-d Ceriodaphnia dubia survival and reproduction test, and various tasks that are associated with these two static-renewal tests (e.g., maintaining cultures of the test animals, water chemistry analyses, quality assurance/quality control needs, sampling, and reporting). This analysis shows that all of these tasks require 53.6 ph/t. For six samples (e.g., five ambient samples plus a control, or five concentrations of an effluent plus a control), the fathead minnow test requires 6.9 ph/t and the Ceriodaphnia test requires 5.8 ph/t. The effort needed to maintain fathead minnow cultures is approximately equal to that needed to maintain C. dubia cultures (5.6 vs. 5.8 ph/t). Effort expended on other components of the testing includes 7.0 ph/t for water chemistry analyses (six samples), 5.5 ph/t for test preparation and takedown, 4.0 ph/t for QA/QC, 6.0 ph/t for report writing, and 7.0 ph/t for sampling. In addition, the analysis explores the economies of scale in conducting the two toxicity tests. Finally, the study provides guidance for those who plan to conduct these tests and for those sponsors who may need a better understanding of the basis for the costs involved.
Mobility of pesticides and their hydrolysis metabolites in soil
Authors: Somasundaram L. , Coats Joel R. , Racke Kenneth D. , Shanbhag Venkatesh M. 
Published: March 2010

Abstract
The soil thin layer chromatography technique was employed to assess the mobility of 21 chemicals (6 insecticides, 4 herbicides, and 11 of their hydrolysis metabolites) in 6 different soils. The hydrolysis products of the four studied organophosphorus insecticides were significantly more mobile than their parent compounds, but the metabolites of carbamates, s triazines and phenoxy alkanoic acids were less mobile than their parent compounds. For the chemicals for which significant effects of soil variables were observed, greater levels of organic matter, clay, cation exchange capacity and water holding capacity (at one-third bar) lowered the mobility Soil pH significantly affected mobility of many of the chemicals studied, with increased mobility in soils with higher pH values. Both water solubility and octanol/water partition coefficient (Kow) significantly correlated with the mobility of the chemicals studied, however, Kow was found to be the better predictor of mobility No direct relationship existed between the pKa of the chemicals and their mobility
A field comparison of two methods for measuring DCPA soil evaporation rates
Authors: Majewski Michael S. , Mcchesney Michael M. , Seiber James N. 
Published: March 2010

Abstract
The theoretical-profile-shape (TPS) method for estimating pesticide evaporative flux from soil was compared to the aerodynamic-profile (AD) method in an intraplot field experiment using dacthal (DCPA) herbicide. Flux values measured by the TPS method were approximately 20% higher than values found by the AD method. Linear regression analysis of soil concentration over an 84-d period showed a soil half-life of 33.8 d. Of the amount lost from soil, 52 and 36% were accounted for by volatilization with the TPS and AD methods, respectively. The volatilization half-life of dacthal based on the 21-d cumulative flux measurements from actual and estimated daily fluxes were 59 and 83 d for the TPS and AD methods, respectively. The results were compared to the 138-d prediction of a published environmental fate model.
Paralytic shellfish toxins seem absent in extracts of diarrhetic shellfish toxins
Authors: Stabell Ole B. , Yndestad Magne , Heidenreich Brit 
Published: March 2010

Abstract
It has been assumed that the water-soluble paralytic shellfish toxins are extracted and concentrated by the organic-solvent extraction method used for diarrhetic shellfish toxins. As diarrhetic toxin extracts of mussels with high levels of paralytic toxins are found nontoxic, it appears that paralytic toxins are not present in those extracts.
Degradation and bound residue formation of four atrazine metabolites, deethylatrazine, deisopropylatrazine, dealkylatrazine and hydroxyatrazine, in a Western Tennessee soil
Authors: Winkelmann D. A. , Klaine S. J. 
Published: March 2010

Abstract
Atrazine (2-chloro-4-[ethylamino]-6-[isopropylamino]-1,3,5-triazine) can be degraded to several metabolites in soil that include the dealkylated metabolites, deethylatrazine (DEA), deisopropylatrazine (DIA) and dealkylatrazine (DAA), and the dechlorinated metabolite, hydroxyatrazine (HYA). Biological and physical degradation and soil-bound residue formation from uniformly 14C ring-labeled DEA, DIA, DAA and HYA were characterized in a western Tennessee soil using intact surface soil core microcosms.
Metabolites were applied to soil microcosms at a rate of 0.5 kg/ha (˜1.2 μg/g soil). Concentrations of the dealkylated metabolites in nonirradiated soil microcosms decreased to less than 2% of the applied compound or were not detected after 180 d incubation. Hydroxyatrazine residues decreased to 33% of the applied concentration. In nonirradiated microcosms after 180 d, evolution of 14CO2 from radiolabeled DEA, DIA, DAA and HYA increased to 25, 16, 59 and 21%, respectively, of the total radiolabel added. Irradiated soil microcosms evolved 0.6, 1.7, 0.1 and 0.9%, respectively, of the total radiolabel added. Rates of dissipation for the four metabolites followed first-order kinetics. Half-lives for the dealkylated metabolites, based on extractable residues, ranged from 17 to 26 d, whereas HYA was 121 d. Soil-bound 14C residues increased in concentration in nonirradiated microcosms and ranged from 28% of the applied radiolabel for HYA to 60% for DEA after 180 d. In irradiated microcosms the range was from 24% for HYA to 72% for DAA on day 180. Extractable 14C residues in all microcosms decreased in concentration during this study and, after 180 d, ranged from 4% of the radioactivity added for DAA to 40% for HYA. Extractable 14C residues in irradiated microcosms ranged from 31% of the initial activity for DAA to 68% for HYA at the termination of the study.
Exposure-related patterns of biochemical indicators in rainbow trout exposed to no. 2 fuel oil
Authors: Steadman B. L. , Farag A. M. , Bergman H. L. 
Published: March 2010

Abstract
Several biochemical indicators were evaluated as monitoring techniques in rainbow trout (Oncorhynchus mykiss) exposed to No. 2 fuel oil (2FO) for their ability to predict the exposure concentration. The principal factor affecting the response of the ratio of liver weight to body weight, microsomal and cytosolic protein, reduced glutathione (GSH), 7-ethoxyresorufin O-deethylation (EROD) and metallothionein (MTN) was the length of exposure, not the exposure concentration. Two patterns of response were observed, depending on the length of exposure. In rainbow trout exposed for 3 d to 12 to 100 mg/L 2FO, cytoplasmic protein and EROD activity were elevated and GSH was depleted; in fish exposed for 21 d, liver size, microsomal and cytoplasmic protein, EROD activity, GSH and MTN were all increased. The appearance of an MTN response due to 2FO exposure causes us to question the use of this protein as a metal bioindicator. Furthermore, we did not observe a dose-dependent response in any of the biochemical responses and suggest that toxicity was responsible for the lack of concentration dependence. This lack of a concentration-dependent response will complicate the use of these biochemical indicators in a biomonitoring program.
Measurement of aquatic contamination by utilizing microsomal enzyme preparations from Carp (Cyprinus carpio) in the Salmonella assay
Authors: Blevins R. Dean 
Published: March 2010

Abstract
The Salmonella typhimurium/mammalian microsome test has provided a simple and sensitive short-term assay for the detection of environmental mutagens. Metabolic activation of precarcinogens is usually achieved by incubating the compound to be tested, the bacterial strain and mammalian liver homogenates with NADPH. The results presented here utilize Salmonella typhimurium strain TA100, the precarcinogen 2-aminofluorene and microsomal enzyme preparations prepared from liver homogenate of carp (Cyprinus carpio) taken from aquatic environments of northeastern Tennessee. Those environments range from virtually unpolluted to extremely polluted. The results show that the precarcinogen 2-aminofluorene is activated either partially or totally in the presence of liver homogenates of carp taken from polluted aquatic environments (e.g., microsomal enzyme preparations made from rat liver with 2-aminofluorene produced 808 revertants; whereas the liver preparations made from carp, taken from the Pigeon River, with 2-aminofluorene produced 2,786 revertants). Revertant colony results correlated well with the degree of pollution within those waters. An increase (data were statistically different at the 0.05 level of significance) of TA100 revertant colonies was observed as aquatic contamination worsened. All data pairs of collecting sites in their order of increasing contamination, as well as those between collecting sites, were statistically different at the 0.05 level of significance.
Effects of environmental variables on binding of a PCB congener by dissolved humic substances
Authors: Jota Mary Anne T. , Hassett John P. 
Published: March 2010

Abstract
The magnitude of the binding interaction of dissolved organic matter with 2,2′,5,5′-tetrachlorobiphenyl is affected by several environmental parameters: pH, ionic strength of the aqueous media, molecular weight and the source of the binding agent. Temperature has little effect. The binding constant for Aldrich humic acid is on the order of 1 × 105. Humic acids extracted from soil and water samples have lower binding capabilities than Aldrich humic acid (KDOC range: 0.24 × 105-0.64 × 105), whereas the fulvic acid and dissolved organic matter samples have KDOCs near the method detection limit (0.086 × 105 and 0.0076 × 105, respectively). Thermodynamic studies show the binding interaction to be entropy driven with ΔH° similar to that of van der Waals's interaction.
Effects of dietary exposure to methyl parathion on egg laying and incubation in mallards
Authors: Bennett Richard S. , Williams Bill A. , Schmedding Dave W. , Bennett Jewel K. 
Published: March 2010

Abstract
An outdoor pen study was conducted with mallards (Anas platyrhynchos) to evaluate the effects of an 8-d dietary exposure to methyl parathion (400 ppm) on egg laying and incubation when treatment was initiated at different times in the nesting cycle. Treatment groups were defined as egg laying (chemical initiated after fourth egg laid in nest), early incubation (initiated after day 4 of incubation), late incubation (initiated after day 16 of incubation) and control (no chemical). Forty-eight pairs (12/group) were allowed to nest and hatch broods. In the egg laying group, daily egg production was reduced significantly during the treatment period compared to controls, but 4 of 10 hens resumed production post-treatment. One of ten control hens abandoned its nest, whereas 17 of 23 hens in the early and late incubation groups either died or exhibited changes in incubation behavior, with 7 hens abandoning their nests and 6 displaying reduced nest attentiveness for one or more days during treatment. Reproductive parameters were not significantly different between treatment groups, but the number of hatchlings per nest was 61, 43 and 58% of controls for the egg laying, early incubation and late incubation groups, respectively. This study showed that nesting success may be impacted by short dietary exposures to methyl parathion, particularly during early incubation.
Toxic effects on algal phosphate uptake
Authors: Nyholm Niels 
Published: March 2010

Abstract
The inhibitory effects on growth and phosphate uptake by two toxicants, 3,5-dichloro-phenol and potassium dichromate, were studied in batch culture experiments with the freshwater green alga Selenastrum capricornutum. The EC50 figures for inhibition of phosphate uptake were considerably smaller than corresponding figures for growth inhibition, but threshold toxicities did not differ as much. Toxic inhibition of phosphate uptake may potentially influence interspecies competition among phytoplankton.
Fate of triclopyr ester (Release®) in a boreal forest stream
Authors: Thompson D.G. , Staznik B. , Fontaine D.D. , Mackay T. , Oliver G.R. , Troth J. 
Published: March 2010

Abstract
The fate of triclopyr butoxyethyl ester was investigated following direct aerial application to a boreal forest stream. The average deposit monitored at the stream surface was 3.67 kg acid equivalent (a.e.)/ha (range = 3.35-3.99 kg a.e./ha). Residues of triclopyr as the butoxyethyl ester (TBEE), triclopyr acid (TRI) and pyridinol metabolite (PYR) were determined in various aquatic substrates. Streamwater residues of TBEE resulting from direct overspray were characterized by instantaneous maxima (0.23-0.35 mg/L). A series of diminishing pulses of chemical associated with inputs upstream of the sampling site were observed. Average concentrations of TBEE in stream water ranged from 0.05 to 0.11 mg/L during the first 12 to 14 h post-application and declined to levels below the limits of quantification (0.001 mg/L) within 72 h post-application. Transient residues of TRI were observed in stream water, with a maximum concentration (0.14 mg/L) 6 h post-application. The PYR residues did not exceed limits of quantification (0.05 mg/L) in any sample. Results indicate that natural dissipation mechanisms reduce both the period and the concentrations to which aquatic organisms would be exposed.
Aquatic hazard assessment of the toxic fraction from the effluent of a petrochemical plant
Authors: Dorn Philip B. , VanCompernolle Remi , Meyer Charles L. , Crossland Norman O. 
Published: March 2010

Abstract
Effluent hazard assessment guidelines were applied to determine the environmental safety of discharged chloroether fractions from a chemical plant effluent. The chloroether fraction was identified as a mixture of pentachloroethers (2,5,6-trichlorohexyl 1′,3′-dichloroisopropyl ether [PCE 1,3] and 2,5,6-trichlorohexyl 2′,3′-dichloropropyl ether [PCE 2,3]), tetrachloropropyl ethers (TCPE; a mixture of l,3,1′,3′-tetrachloroisopropyl ether, 1,3-dichloroisopropyl 2′3′-dichloropropyl ether, and 2,3,2′,3′-tetrachloropropyl ether), 1,2,5,6 tetrachlorohexane (TCH), and related components. The fractions were identified in a toxicity identification evaluation (TIE). The chloroether mixture was acutely toxic between 1.5 and 20 mg/L and had no observed effect concentrations (NOEC) for chronic toxicity from 1 to 3.2 mg/L. Individual chloroether components showed acute toxicity (LC50) from 1.5 to 56 mg/L. Acute toxicity predictions from U.S. Environmental Protection Agency (U.S. EPA) structure-activity relationships (SAR) were within a factor of four. Acute to chronic ratios for specific chloroether components were between 3 and 14. Sediment studies showed moderate sorption of TCPE with a log Koc between 2.7 and 2.9. The log Kow was 3.2 for TCPE, and the bioconcentration potential (logBCF) for the mixture was &lt; 2.7. Laboratory and field stream experiments confirmed laboratory predictions for toxicity, with NOEC for trout growth &gt; 0.26 mg/L and effects on Gammarus feeding at 0.44 mg/L of the mixture.