bluuebunny/crossref_metadata_2025_split huggingface dataset:
Elimination rates of selected di-Ortho, mono-ortho, and non-orthosubstituted polychlorinated biphenyls in rainbow trout (oncorhynchus mykiss)
Authors: Coristine S. , Haffner G.D. , Ciborowski J.J.H. , Lazar R. , Nanni M.E. , Metcalfe C.D. 
Published: March 2010

AbstractIn order to determine the influence of chlorine substitution pattern on elimination rate constants for polychlorinated biphenyls (PCBs), 60 rainbow trout (Oncorhynchus mykiss) were intraperitoneally injected with corn oil spiked with a mixture of 13 tetra- to hexachlorobiphenyls. The mixture consisted of four di-ortho congeners (International Union of Pure and Applied Chemistry no. 52, 47, 101, and 153), five mono-ortho congeners (66, 105, 118, 119, and 156), and four non-ortho congeners (81, 77, 126, and 169). The range in growth-corrected elimination rate constants for the non-ortho-substituted PCBs was 0.003 to 0.015 μg/kg per d. The range of elimination rate constants for the mono-ortho PCBs was 0.007 to 0.012 μg/kg per d, and the range for the di-ortho PCBs was 0.004 to 0.011 μg/kg per d. Multivariate analysis of covariance revealed a highly significant interaction between chlorine substitution pattern and time (p &lt; 0.001), suggesting that substitution pattern influences elimination kinetics. Kow and time also revealed a significant interaction (p &lt; 0.001). As structure can influence rates of chemical elimination, exposure dynamics of PCBs are a function of both hydrophobicity and substitution patterns. The study confirms the observation that the predicted rate of decline of some of the more toxic non-ortho PCBs might be less than that observed for total PCBs.
Bioaccumulation and metabolism of benzo[A]pyrene in three species of polychaete worms
Authors: Driscoll Susan Kane , McElroy Anne E. 
Published: March 2010

Abstract
Polychaete worms which inhabit and ingest contaminated sediments may be exposed to a suite of sediment-sorbed xenobiotics, including polycyclic aromatic hydrocarbons (PAHs) such as benzo[a]pyrene (BaP). This study compared the accumulation and metabolism of sediment-sorbed BaP among various populations of polychaetes, including Leitoscoloplos fragilis, Nereis diversicolor, and Scolecolepides (= Marenzellaria) viridis. After exposure to trace amounts of BaP in sediment, N. diversicolor and S. viridis were found to metabolize BaP extensively, but metabolism of BaP appeared to be much slower in L. fragilis. Within each species, no consistent, significant differences in extent of BaP metabolism were observed between worms collected from contaminated versus reference sites. This result suggests that metabolism of BaP was not induced in worms from contaminated sites. To examine the extent to which metabolism of BaP is inducible in these species, worms were exposed in the lab to 3-methylcholanthrene (3MC), a potent inducer of PAH metabolism in other species. Only one species, S. viridis, showed a small increase in the percent of total tissue BaP that was biotransformed after treatment with 3MC. Whether or not worms were treated with 3MC, biota-sediment accumulation factors (lipid- and organic carbon-normalized tissue to sediment ratios) were highest for L. fragilis.
Effect of sediment organic carbon on the toxicity of a surfactant to Hyalella azteca
Authors: Cano Manuel L. , Dyer Scott D. , Decarvalho Alvaro J. 
Published: March 2010

Abstract
According to current sediment bioavailability models (e.g., equilibrium partitioning), toxicity of sorptive compounds in sediment depends on the free concentration in interstitial water. This free concentration may depend on both the characteristics of the compound and the sediment. For the sorption of anionic surfactants, sediment organic carbon content and cation exchange capacity have been shown to be important factors; however, it is not clear how these factors affect toxicity. Determining toxicity of these compounds in sediment using traditional batch sediment tests has not been entirely successful in the past due to excessive loss of parent material via biodegradation. In this study, effects of organic carbon on anionic surfactant toxicity were determined using highly branched alkylbenzene sulfonate (ABS) as the test compound in order to limit losses from biodegradation. Sediments were amended with peat moss to investigate the effects of organic carbon on surfactant sorption and toxicity to Hyalella azteca. Results support previous hypotheses regarding the effect of organic carbon on bioavailability and toxicity. Apparent sorption coefficients (Kapp) increased with higher organic carbon levels. Likewise, greater sediment concentrations of ABS were required to elicit toxic responses at greater organic carbon concentrations. Toxicity in sediment appeared to be due to interstitial water exposure.
Environmental loads from water-sprinkled softwood timber: 2. Influence of tree species and water characteristics on wastewater discharges
Authors: Borga Peter , Elowson Torbjörn , Liukko Kari 
Published: March 2010

Abstract
The concentration patterns of a number of compounds in the inlet water and wastewater from sprinkling of timber from Scotch pine and Norway spruce have been studied. The timber was separated with respect to species and sprinkled with water from a eutrophic or an oligotrophic receiving water for 18 weeks. Organic and inorganic compounds including dissolved organic carbon (DOC), distillable phenols, resin acids, bacterial phospholipid fatty acids, organic and inorganic phosphorus, nitrogen and sulphur, and a number of metal ions were monitored in the inlet water and wastewater. The toxicity of the wastewater was estimated during the first 2 weeks using a Microtox® test and appeared to decline in parallel with DOC. Most compounds showed both an environmental net load and an absorption by the timber, the loads being smaller and the absorption larger when using eutrophic water. At both sites the loads were generally largest during the first 2 weeks and larger in magnitude at the oligotrophic site and in the spruce wastewater. The initial growth of the bacterial biomass in the pile system was slower at the oligotrophic site, and the results indicated that a rapid growth of the bacterial biomass reduces the initial environmental loads and that this process is associated with the nutrient status of the receiving water.
Occurrence, sources, and fate of trichloroacetic acid in swiss waters
Authors: Müller Stephan R. , Zweifel Hans-Rudolf , Kinnison David J. , Jacobsen Jens A. , Meier Markus A. , Ulrich Markus M. , Schwarzenbach René P. 
Published: March 2010

Abstract
The occurrence, sources, and fate of trichloroacetic acid (TCA) has been investigated in surface waters, ground waters, drinking waters, wastewaters, and rainwater in Switzerland. The concentrations found in surface waters varied between less than 27 ng/L (limit of quantification) and 340 ng/L, whereas the concentrations in ground water were always below 27 ng/L. It was found that the main sources of TCA in surface waters were the effluents of wastewater treatment plants (average concentration, 430 ng/L; range, 40-1060 ng/L). The average TCA concentration in rainwater was 300 ng/L range, (&lt;27-900 ng/L). A dynamic mathematical model revealed that TCA is not significantly degraded in a lake (half-life &gt;230 d). A detailed mass balance in the catchment area of a small lake (Greifensee) and a very rough mass balance over Switzerland indicate that rain is the major source of TCA in Switzerland (&gt;90%), but they also show that about 60 to 80% of the TCA deposited by rain is eliminated, most probably in the soil.
Triphenyltin and its degradation products in foliage and soils from sprayed pecan orchards and in fish from adjacent ponds
Authors: Kannan Kurunthachalam , Lee Richard F. 
Published: March 2010

Abstract
Triphenyltin (TPT) is a fungicide used on a variety of crops throughout the world. In this study, pecan orchards in central Georgia (USA) previously sprayed with commercial TPT hydroxide mixtures were found to have TPT concentrations of 8.5 to 37 μg/g dry weight in foliage and 1.2 to 12 μg/g dry weight in soil. Total phenyltin concentrations (monophenyltin [MPT] + diphenyltin [DPT] + TPT) in foliage and soils immediately after application were up to 72 and 26 μg/g dry weight, respectively. Besides TPT, DPT and MPT were present in the leaves and soils, with MPT generally the predominant compound. The proportion of MPT to TPT in pecan leaves increased with time after spraying, which was indicative of photolytic degradation of TPT. Microbial degradation of radiolableled TPT in soil or sediment samples was slow, with only 5% degraded during a 14-d incubation period. Triphenyltin was absent from the subsurface soils (2 to 15 cm depth) even though it had been sprayed eight to 10 times a year at a rate of 850 g/ha for the past 10 years. In an orchard where the last spraying was carried out approx. 2 years ago, TPT was absent, but MPT was present at approximately the same concentration as recently sprayed orchards. Fish (blue gill, largemouth bass, and channel catfish) from a pond near a recently sprayed pecan orchard had TPT as well as DPT and MPT. The predominate phenyltin in all fish was MPT, with 22 μg/g wet weight in the liver of catfish. Radiolabeled TPT was only slowly metabolized by the fathead minnow, with 2% of the TPT metabolized to DPT after 6 d of exposure via water. Photodegradation appears to be the major factor affecting the fate of TPT in soils.
Toxicity of sediment-associated pyrene and phenanthrene to Limnodrilus hoffmeisteri (oligochaeta: Tubificidae)
Authors: Lotufo Guilherme R. , Fleeger John W. 
Published: March 2010

Abstract
Acute and sublethal toxicities of sediment-spiked pyrene and phenanthrene to Limnodrilus hoffmeisteri Cleparéde were investigated. Phenanthrene was acutely toxic at high sediment concentrations (10-d median lethal concentration of 297.5 μg g−1; 252.2-348.3, 95% confidence interval [CI]). Pyrene was not acutely toxic, even at concentrations as high as 841 μg g−1. A significant impact of pyrene and phenanthrene on the feeding activity of L. hoffmeisteri was demonstrated through daily collection of egested fecal material during 5- and 10-d experiments. A short (5-d) exposure detected toxic effects more efficiently than a 10-d exposure, yielding IC25 values (estimated concentration causing a 25% reduction of measured endpoint in relation to the control[s]) of 58.9 μg g−1 (32.1-89.4, 95% CI) for pyrene and 28.4 μg g−1 (10.0-41.3, 95% CI) for phenanthrene. Effects on burrowing behavior and reproduction were assessed in a 28-d sediment exposure. Low burrowing avoidance (&lt;25%) was detected in high phenanthrene concentrations (143-612 μg g−1) but was not detected with pyrene. Offspring production was significantly reduced in dosed sediments yielding IC25 values of 59.1 μg g−1 (38.3-112.5, 95% CI) for pyrene and 40.5 μg g−1 (12.1-165.5, 95% CI) for phenanthrene. Decreases in egestion rates in the presence of nonpolar contaminants should be quantified when investigating the effects of bioturbation by deposit feeders on the flux of contaminants from sediment into the water column.
Comparison of nonplanar and coplanar PCB congener partitioning in seawater and bioaccumulation in blue mussels (Mytilus edulis)
Authors: Bergen Barbara J. , Nelson William G. , Pruell Richard J. 
Published: March 2010

Abstract
The partitioning of 18 nonplanar and three coplanar (International Union of Pure and Applied Chemistry [IUPAC] numbers 77, 126, and 169) polychlorinated biphenyl (PCB) congeners was quantified in New Bedford Harbor, Massachusetts, USA. Concurrently, bioaccumulation of these congeners was measured in blue mussels deployed for 7 and 28 d in New Bedford Harbor, and bioconcentration factors (BCFs) were calculated for each congener. The PCB concentrations measured in the dissolved and particulate fractions of seawater samples were used to calculate partition coefficients (Kp) for each congener. These values were correlated with reported octanol/water partition coefficients (Kow). No significant differences (p &gt; 0.05) were observed in the relationships between Kp and Kow for the coplanar congeners relative to the nonplanar congeners. Coplanar congeners reached steady state faster than the nonplanar congeners; however, after 28 d a similar relationship was observed between BCF and Kow in coplanar and nonplanar congeners. These data indicate that coplanar PCBs partition in seawater and accumulate in mussels similarly to nonplanar PCBs with the same number of chlorines.
A bleached-kraft mill effluent fraction causing induction of a fish mixed-function oxygenase enzyme
Authors: Burnison B. Kent , Hodson Peter V. , Nuttley Donna J. , Efler Sue 
Published: March 2010

Abstract
Pulp mill effluents contain a myriad of chemicals that have the potential to cause deleterious effects on aquatic biota in receiving waters. Some of these chemicals evoke an acute lethal response of exposed biota while others evoke sublethal responses. One such sublethal response is the induction of mixed-function oxygenases (MFO) in fish, specifically the CYP1A1 enzyme ethoxyresorufin-o-deethylase (EROD). We followed the partitioning of the inducing chemicals in pulp mill effluent fractions by Toxicity Identification Evaluation (TIE), or bioassay-driven chemical analysis. This procedure was eventually modified to a more direct technique involving centrifugation, filtration, cleanup procedures, and C18 solid-phase adsorption. The extracts from the fractionation of two pulp mill effluents after secondary treatment were tested for EROD-inducing activity in a 4-d rainbow trout bioassay. The methanol extracts of particulates/colloids showed significant inducing capacity in Mill A effluent but not in Mill B effluent. The C18 methanol extracts induced activity from both effluents, with extracts from Mill A causing the greatest response. The particulate/colloidal extract (Mill A) was used as the source material for chemicals which caused EROD induction. The fraction was purified by solid-phase extraction techniques and reverse-phase high-performance liquid chromatography. The majority of the EROD activity was found in the moderately nonpolar region of the chromatogram (Kow = 4.6 to 5.1).
Survival and cover-seeking response of northern bobwhites and mourning doves dosed with aldicarb
Authors: Hawkes Anthony W. , Brewer Larry W. , Hooper Michael J. , Kendall Ronald J. , Hobson James F. 
Published: March 2010

Abstract
Survival and cover-seeking responses of wild northern bobwhites (Colinus virginianus) and mourning doves (Zenaida macroura) dosed with aldicarb were investigated. Acute toxicity range-finding tests were conducted to establish optimum dose levels for subsequent dose–release activities. Estimated median lethal dose values derived for doves and bobwhites were 0.82 and 1.48 mg/kg body weight, respectively. Wild mourning doves and northern bobwhites were orally administered aldicarb or a vehicle blank and monitored for 7 d posttreatment to determine survival and cover-seeking response. Doves receiving the highest aldicarb concentration (1.07 mg/kg bodyweight) had a significantly lower survival rate than did controls. However, when mortalities attributable to acute toxicity were removed from the analysis, there were no differences in daily survival rates among treatment groups. All bobwhite treatment groups had lower survival rates than controls. When acute mortalities were removed from the survival analysis, the 1.36-mg/kg bodyweight treatment group still had a significantly lower survival rate than controls. Postdose observations of behavior indicate that mourning doves and northern bobwhites receiving a lethal dose of aldicarb are limited in their cover-seeking ability due to the rapid onset of physical impairment associated with this compound.
Development of a plant bioassay to assess toxicity of chemical stressors to emergent macrophytes
Authors: Powell Rebecca L. , Kimerle Richard A. , Moser E. Michelle 
Published: March 2010

Abstract
A static renewal bioassay has been proposed to evaluate the effects of chemical stressors on the growth of emergent macrophytes. Bioassay methods were developed using Oryza sativa L. (domestic rice) as the test species and boron as the test compound. After culturing O. sativa in a natural sediment for 2 weeks, the plants were continuously exposed to various concentrations of boron dissolved in the dilution water. At the end of the exposure period the plants were evaluated. Endpoints included visual observations, dry weight, residue, and chlorophyll concentration in the leaf tissue. Dose–response relationships were established for each endpoint; however, dry weight appears to be the least sensitive endpoint. Exposure duration also significantly influenced toxic values. The bioassay procedure was then used to screen several other emergent macrophytes for toxicity to boron. Visual observations and residue indicated treatment differences for each of these species; however, dry weight and chlorophyll concentration did not confirm the differences. Oryza sativa plants exposed to water naturally contaminated with boron accumulated similar concentrations of boron in their leaf tissue as plants exposed to laboratory-prepared solutions of boron. Based on the data presented here, this bioassay appears to be useful in evaluating the potential toxicity of chemical stressors to emergent macrophytes.
Evaluating the environmental fate of a variety of types of chemicals using the EQC model
Authors: Mackay Donald , Di Guardo Antonio , Paterson Sally , Cowan Christina E. 
Published: March 2010

Abstract
The multimedia equilibrium criterion model, which can be used to evaluate the environmental fate of a variety of chemicals, is described. The model treats chemicals that fall into three categories. In the first the chemicals may partition into all environmental media, in the second they are involatile, and in the third they are insoluble in water. The structure of the model, the process equations, and the required input data for each chemical type are described. By undertaking a sequence of level I, II, and III calculations, increasing information is obtained about the chemical's partitioning, its susceptibility to transformation and transport, and the environmental process and the chemical characteristics that most influence chemical fate. Output data, consisting of tables and charts, give a complete picture of the chemical's fate in an evaluative or generic environment. The model is illustrated by applying it to two chemicals, pyrene, which is a chemical of the first type, and lead, which is of a second type. The role of this model as a tool for assessing the fate of new and existing chemicals is discussed.
Bioconcentration and metabolism of [14C]3-chloro-P-toluidine hydrochloride by Bluegill Sunfish
Authors: Spanggord Ronald J. , Gordon G. Ross , Schocken Mark J. , Starr Robert I. 
Published: March 2010

Abstract
Bluegill sunfish (Lepomis macrochirus) were continuously exposed to 0.1 μg/ml of uniformly radiolabeled [14C]3-chloro-p-toluidine hydrochloride (CPTH) for 28 d, after which the fish were transferred to flowing untreated water for a 28-d depuration period. At periodic intervals during the treatment and depuration periods, samples of water and fish were analyzed for [14C] residues to determine the degree of CPTH absorption. Samples of bluegill that were exposed to the radiolabeled chemical for 28 d were analyzed to determine the distribution of the radiolabel and to isolate and identify possible metabolites. The steady-state concentrations in the bluegill tissues were reached by day 7 of exposure to the radiolabeled compound, with mean concentrations in the edible, nonedible, and whole-body tissues determined to be 2.9, 12.0, and 7.5 μg/g of tissue, respectively. Bioconcentration factors of 33×, 150×, and 88× were calculated for the three types of tissues. About 64% of the accumulated radiolabeled CPTH and metabolites were eliminated from the fish on day 28 of depuration. The distribution of radioactivity was found to be similar in all tissue groups. One metabolite was confirmed as N-acetyl-3-chloro-p-toluidine, with two metabolites suggested to be 4-acetamido-2-chlorobenzoic acid and 4-amino-2-chlorobenzoic acid. The N-acetylated breakdown product has been previously reported to occur in both mammals and birds; thus, the metabolism of CPTH in fish may parallel that observed in these other species. Although the effects of biomagnification cannot be fully assessed at this time, we can conclude that when bluegill sunfish are continuously exposed to sublethal levels of CPTH, bioconcentration will not occur to an appreciable extent, and that residues will be rapidly excreted upon removal of the fish from the CPTH source. Furthermore, published information pertaining to various aquatic organisms indicates that bioaccumulation will not be a problem if the bioconcentration factor is below 100.
Aerobic biodegradation of [14C]3-chloro-P-toluidine hydrochloride in a loam soil
Authors: Spanggord Ronald J. , Gordon G. Ross , Starr Robert I. , Elias Donald J. 
Published: March 2010

AbstractDegradation of the pesticide 3-chloro-p-toluidine hydrochloride (CPTH) occurred in a loam soil when applied at concentrations of 3.5 and 35 μg/g. The compound degraded according to pseudo-first-order kinetics, with a calculated rate constant of 2.74 × 10−2 h−1, at a soil temperature of 22°C; this rate constant yielded a half-life of 25 h. The loss of radiolabeled CPTH from soil was suggested to be controlled by both irreversible binding to the soil colloids and microbial transformation. Mineralization of the radiolabeled CPTH was interpreted as involving two zero-order kinetic rates; an initial rate of carbon dioxide release was estimated to be 0.33% d−1 (half-life of 152 d), followed by a slower rate of 0.07% d−1, which resulted in a half-life of 718 d. Approximately 13% of the radiolabeled CPTH that was applied to soil at 3.5 μg/g was mineralized to [14C] carbon dioxide during the 99-d incubation period. A primary metabolite was identified as N-acetyl-3-chloro-p-toluidine (ACPTH); this metabolite reached a maximum concentration at the 1-d sampling period, and degraded with a pseudo-first-order rate constant of 2.67 × 10−2 h−1; the half-life for ACPTH was calculated to be 26 h. When CPTH was applied to soil at 35 μg/g, the compound was also mineralized in soil by a similar metabolic pathway to that observed at the lower concentration. However, the rate of mineralization was slower, which suggests that elevated soil concentrations of CPTH may affect the viability of certain microorganisms.