bluuebunny/crossref_metadata_2025_split huggingface dataset:
Volatile sulfides and their toxicity in freshwater sediments
Authors: Brouwer Henry , Murphy Tom 
Published: March 2010

Abstract
Three forms of volatile sulfides (free hydrogen sulfide, acid-volatile sulfides [AVS] and a new form, heat-volatile sulfides [HVS]), were measured and their relationships discussed. Purging of some contaminated sediments with nitrogen at 22°C failed to remove all of the free H2S, even after 6 h. With freshly H2S-spiked uncontaminated sediment, purging of H2S was complete after 2 h; however, if the spiked sediment was allowed to stand for 53 d, H2S continued to be purged, even after 43 h. The H2S likely originates from equilibrium reactions involving reduced sulfur species in the sediment. Uncontaminated sediment spiked with H2S was found to be highly toxic using a sediment-contact bioassay employing Photobacterium phosphoreum. Addition of Fe3+, which sequesters the S2−, reduced the toxicity. Two other bioassays (ATP-TOX and Toxi-Chromotest), both involving a DMSO/methanol extract of the spiked sediment, showed greatest toxicity with spiked sediment that had been standing for 22 d. The results indicate that reduced sulfur species in sediment may be a cause of toxicity observed in contaminated anoxic sediments.
Investigating the influence of incomplete separation of sediment and water on experimental sorption coefficients of chlorinated benzenes
Authors: Schrap S. Marca , Haller Manuela , Opperhuizen Antoon 
Published: March 2010

Abstract
The influence of incomplete separation of water and sediment in batch sorption experiments was investigated with five chlorinated benzenes (sediment/water ratios between 0.25 and 50 g/L). Only the sorption coefficients of the most hydrophobic chemical, hexachlorobenzene, decreased with increasing sediment/water ratios. This decrease is assumed to be caused by an increasing amount of sediment that was not separated from the aqueous phase. To quantify this incomplete water/sediment separation, the unseparated sediment fraction, called the third phase, was analyzed in suspension water. For this purpose the apparent enhanced solubilities of hexachlorobenzene and two polychlorinated biphenyls were determined in the suspension water. Solubilities of these compounds were found to be considerably enhanced (up to about 8 times). In addition, turbidity, dry weight, and dissolved organic carbon (DOC) measurements were used to quantify the third phase. On the basis of these third-phase analyses, experimental sorption coefficients of hexachlorobenzene were corrected for third-phase influence, where the apparent solubility measurements were the most successful.
Swelling of peats in liquid methyl, tetramethylene and propyl sulfoxides and in liquid propyl sulfone
Authors: Lyon William G. 
Published: March 2010

Abstract
The interactions of methyl, tetramethylene, and propyl sulfoxides and propyl sulfone during sorption onto four dewaxed, acid-form peats have been studied by means of swelling measurements. The results for sulfoxides are displayed as heteromolecular sorption isotherms, which plot amount sorbed versus S=O group activity (molar density ratio relative to methyl sulfoxide). The present swelling data are compared to previous data for a homologous series of alcohols. Propyl sulfone apparently reacted with the peats during the sorption process, and one peat (Canadian) exhibited a dramatic 26% shrinkage in volume when exposed to this reagent for 8 weeks. Pyrolysis-GC-MS study of sulfone-doped Canadian peat found that propyl sulfide was the predominant pyrolysis product, although traces of propyl sulfoxide and sulfur dioxide were also found.
Use of estuarine water column tests for detecting toxic conditions in ambient areas of the chesapeake bay watershed
Authors: Hall Lenwood W. , Ziegenfuss Michael C. , Anderson Ronald D. , Killen William D. 
Published: March 2010

Abstract
Various estuarine water column toxicity tests were conducted twice in nine different ambient stations in the Chesapeake Bay watershed over a 2-year period (1991 to 1993) to determine if toxic conditions existed. The following 8-d toxicity tests were conducted: larval sheepshead minnow (Cyprinodon variegatus) survival and growth test; larval grass shrimp (Palaemonetes pugio) survival and growth test; and a copepod (Eurytemora affinis) life-cycle test. During the second year of testing, two 48-h coot clam (Mulinia lateralis) tests were conducted at each station during each testing period. In 1991, the toxicity tests were conducted twice at stations in the Potomac River at Morgantown and Dahlgren, and in the Patapsco River and the Wye River at the Manor House. All of the above tests were conducted during the fall of 1992 and spring of 1993 at two stations in the Wye River, Nanticoke River, and Middle River. Inorganic contaminants, organic contaminants, and water-quality conditions were measured concurrently during the toxicity testing of ambient water. In 1991, reduced growth of sheepshead minnow larvae was reported at both Potomac River stations during the first test. Significant mortality of either the copepod or sheepshead minnow larvae was also reported at the Wye River during both tests. Results from the 1992/93 testing generally showed minimal effects for three of the test species at all stations. Reduced normal shell development was reported for the coot clam at both Middle River stations during the fall and spring tests concurrently with concentrations of various trace metals that exceeded chronic marine water-quality criteria.
Effects of biologically treated bleached-kraft mill effluent before and after mill conversion to increased chlorine dioxide substitution: Results of an experimental streams study
Authors: Haley Richard K. , Hall Timothy J. , Bousquet Theresa M. 
Published: March 2010

Abstract
Large-scale outdoor experimental streams were used to determine the effects of effluent on stream biota before and after conversion of a bleached-kraft mill to increased chlorine dioxide substitution. Data for long-term (6 to 9 months) exposures at 1.5 and 5 0% v/v effluent in periods before and after conversion were compared for effluent quality, rainbow trout (Oncorhynchus mykiss) production, growth, survival, and histopathology, and periphyton and macroinvertebrate community characteristics. Data for cytochrome P4501A and ethoxyresorufin O-deethylase (EROD) biomarkers in trout were obtained in an additional 1 5-month postconversion exposure. Postconversion effluent was characterized by reduced chlorinated organic constituents and adsorbable organic halides. Rainbow trout in both the pre- and postconversion periods indicated a pattern of greater size, fewer numbers, and equal or greater production in the effluent-exposed populations compared to unexposed controls. Fish health measurements, including histopathology, hematology, and liver somatic indices, did not indicate significant negative effects, contrasting with the biomarkers, where there was a significant, positive dose-response relationship with similar effluent exposures. The lack of major differences in fish and other stream biota responses following the reductions in effluent chlorinated organic compounds raises questions about the ecological relevance of these compounds at the concentrations tested.
White sucker (Catostomus commersoni) growth and sexual maturation in pulp mill-contaminated and reference rivers
Authors: Gagnon M. M. , Bussieres D. , Dodson J. J. , Hodson P. V. 
Published: March 2010

Abstract
Induction of hepatic ethoxyresorufin-O-deethylase (EROD) activity and accumulation of chlorophenolic compounds typical of bleached-kraft mill effluent (BKME) in fish sampled downstream of a pulp mill on the St. Maurice River, Québec, Canada, provided evidence of chemical exposure to BKME. In comparison, fish sampled over the same distances and in similar habitats in a noncontaminated reference river, the Gatineau River, demonstrated low EROD activity and contamination levels. Accelerated growth of white suckers occurred between 2 and 10 years of age in both rivers at downstream stations relative to upstream stations, suggesting the existence of gradients of nutrient enrichment independent of BKME contamination. The impact of BKME exposure was expressed as reduced investment in reproduction, as revealed by greater length at maturity, reduced gonad size, and more variable fecundity. These effects were not obvious in simple upstream-downstream comparisons, but became evident when fish from the uncontaminated Gatineau River showed increased gonadal development and reduced age and size at maturity in response to enhanced growth rates.
Toxicity of arsenic, molybdenum and selenium combinations to Ceriodaphnia dubia
Authors: Naddy Rami B. , La Point Thomas W. , Klaine Stephen J. 
Published: March 2010

Abstract
Previous research done on the effects of contaminant mixtures has been evaluated primarily by using acute exposures. While this was an important initial step, characterizing the effects of chronic exposures of these mixtures is more environmentally pragmatic. This study examined the sublethal interactive effects of arsenic (As), molybdenum (Mo), and selenium (Se) on Ceriodaphnia dubia using the three-brood static renewal toxicity test. A complete factorial design experiment using four levels (zero, IC12.5, IC25, and IC50 values) of each metal was performed to investigate the binary and tertiary interactions of these metals on C. dubia survival and fecundity. Results indicate three-way interactive effects in survival and fecundity with the strongest effect exhibited by Se. Molybdenum and As in binary combinations appear to be strongly antagonistic in their effects on C. dubia, even at their respective IC50 concentrations. However, generally the addition of Se to As-Mo mixtures significantly reduced survival and reproduction. The IC50 concentrations of either Mo or Se significantly reduced fecundity in all binary and tertiary mixtures. All tertiary metal mixtures, except the combination of the IC12.5 concentrations of each metal, significantly reduced C. dubia fecundity.
Predicting chronic lethality of chemicals to fishes from acute toxicity test data: Multifactor probit analysis
Authors: Lee Gunhee , Ellersieck Mark R. , Mayer Foster L. , Krause Gary F. 
Published: March 2010

Abstract
New methods for predicting chronic toxicity (lethality) from acute lethality data with fishes was developed and assessed. Typically, acute toxicity tests with aquatic organisms provide lethality estimates for a series of toxicant concentrations at 24, 48, 72, and 96 h of exposure. Statistical models (multiple regression) were developed that utilize acute toxicity data to establish the relation of lethality to toxicant concentration and exposure time for predicting chronic lethality. The models provide estimates of toxicant concentrations that result in a low probability of death as a function of extended exposure times. Results from 28 data sets having lethality data for both acute and chronic exposures were used to evaluate the method. It is posited that the proposed methods are highly accurate when acute lethality data meeting stated quality requirements are available.
An ecological risk assessment method for species exposed to contaminant mixtures
Authors: Logan Dennis T. , Wilson Harold T. 
Published: March 2010

AbstractThe method developed here provides a quantitative, objective measure of ecological risk for natural populations exposed to mixtures of chemical contaminants. It is founded on generally accepted risk assessment concepts: use of toxic units to assess the joint toxic effects of mixtures and expression of ecological risk as a relationship between toxicological end points and estimated environmental concentrations. Toxicologicai end points may be regulatory levels with zero variance and species-dependent concentrations with estimates of variance. Risk is the probability that a linear combination of toxic units exceeds 1, which expresses the probability that a measurement end point (e.g., 50% mortality in 96 h) will occur. Computations have three variations. One addresses concentration addition, in which chemicals act independently to produce similar biological effects. For noninteractive joint action with no addition, in which the biological response to the mixture is not significantly different from the response to the most toxic component, the method reduces to an analysis of extrapolation error. For other noninteractive joint action — antagonism, partial addition, and supra-addition — a correction factor similar to Konemann's mixture toxicity index is applied. An initial validation using published data indicated that increased in situ striped bass mortality was generally associated with elevated risk estimates. The method is applicable to many organisms and toxicant mixtures.
Organic ligands reduce copper toxicity in Pseudomonas syringae
Authors: Azenha Manuel , Vasconcelos M. Teresa , Cabral João P. S. 
Published: March 2010

Abstract
Pseudomonas syringae cells were exposed to 100 μM copper alone, or to previously equilibrated copper sulfate-ligand solutions. Ligand concentrations were determined experimentally as those that reduced the free copper concentration to 5 μM (determined with a Cu2+-selective electrode). These values were in agreement with those calculated by computational equilibrium simulation based on published stability constants. Exposure of P. syringae cells to copper sulfate, chloride, or nitrate resulted in similar high mortality, suggesting that copper was responsible for cell death. Acetate, succinate, proline, lysine, cysteine, and EDTA significantly reduced both the amount of copper bound to the cells and cell death, indicating that not only strong chelating agents but also weak and moderate copper ligands can effectively antagonize copper toxicity. However, cysteine and EDTA were considerably more effective than acetate, succinate, proline, and lysine, indicating that copper toxicity is not simply a function of free copper concentration but depends on the nature of the ligand. The results suggested that a significant fraction of copper bound to acetate, succinate, proline, or lysine was displaced to the bacteria or, alternatively, mixed copper-ligand-cell complexes could be formed. On the contrary, none of these phenomena occurred for the copper complexes with cysteine or EDTA.
Check studies with Hyalella azteca and Chironomus tentans in support of the development of a sediment quality criterion for dieldrin
Authors: Hoke Robert A. , Kosian Patricia A. , Cotter Anne M. , van dermeiden Frances M. , Ankley Gerald T. , Phipps Gary L. , Durhan Elizabeth J. 
Published: March 2010

Abstract
The development of sediment quality criteria (SQCs) for nonpolar compounds using equilibrium partitioning theory (EqP) requires three critical data elements for the compound of interest: (a) a reliable, measured Kow; (b) an acceptable minimum data set for the development of the final acute and final chronic values necessary to calculate a water-quality criterion (WQC); and (c) “check” experiments with appropriate freshwater and marine benthic organisms to ensure that their responses in spiked-sediment tests are in agreement with responses predicted based on EqP. This study presents the results of dieldrin check experiments with two freshwater species: the amphipod Hyalella azteca and the chironomid Chironomus tentans. Ten-day, flowthrough, water-only dieldrin LC50 values for the amphipod and chironomid were 7.6 and 1.1 μg/L, respectively. The LC50 values for the two species based on organic carbon-normalized sediment concentrations of dieldrin were generally less variable than values based on dieldrin concentrations in sediments on a dry-weight basis. Ten-day LC50 values for H. azteca and C. tentans based on measured pore-water concentrations of dieldrin were greater than those based on EqP-predicted pore-water concentrations of dieldrin. An increase in the apparent water solubility of dieldrin as a result of binding to dissolved organic carbon appeared to account for this phenomenon. Ten-day LC50 values for H. azteca and C. tentans based on EqP-predicted pore-water concentrations of dieldrin were within a factor of 25 and 3 of their respective 10-d, water-only dieldrin LC50 values. Avoidance of the dieldrin-spiked sediments may offer a partial explanation for the concentration-response results observed with H. azteca and the greater difference observed for this species between water-only and predicted pore-water 10-d LC50 values for dieldrin. Inhibition of growth in C. tentans was also a sensitive end point with effects observed at pore-water concentrations of dieldrin as small as 5.5 μg/g organic carbon. Based on these results, it appears that EqP based upon sediment organic carbon content is an appropriate model for converting WQC for dieldrin to SQC. These results also highlight the importance of using multiple benthic test species (including at least one infaunal species), end points, and sediments in SQC sediment-spiking check studies.
Effects of a complex mixture of chemical contaminants on hepatic glutathione, L-cysteine and γ-glutamylcysteine synthetase in english sole (Pleuronectes vetulus)
Authors: Nishimoto Marc , Le Eberhart Bich-Thuy , Sanborn Herbert R. , Krone Cheryl , Varanasi Usha , Stein John E. 
Published: March 2010

Abstract
The effects of chemical contaminants on concentrations of hepatic glutathione (GSH), cysteine (L-Cys), and the activity of γ-glutamylcysteine synthetase (γ-GCS) were assessed in English sole (Pleuronectes vetulus) in the laboratory and in fish from the Duwamish Waterway, a contaminated urban site in Puget Sound, Washington. In the laboratory studies, fish from a nonurban (reference) site were exposed to an organic-solvent extract of sediment from the Duwamish Waterway. Hepatic GSH concentrations significantly increased at 3 d after exposure to the extract at 1,000 g sediment extracted/kg fish. At this time point, hepatic GSH showed a dose-dependent increase at dosages ranging from 300 to 1,600 g sediment extracted/kg fish, whereas fish exposed to a reference sediment extract showed no increase. Moreover, the increases in GSH in fish exposed to the contaminated sediment extract were not accompanied by changes in either L-Cys concentrations or γ-GCS activity. Similarly, fish sampled directly from the Duwamish Waterway showed increased GSH concentrations but showed no significant differences in L-Cys levels or γ-GCS activity compared to fish from a reference site. These results substantiate that hepatic GSH in fish is responsive to chemical contaminant exposure and further support its use as a biomarker in environmental monitoring studies. The findings also indicate that L-Cys availability and induction of γ-GCS were not major factors in the increase of hepatic GSH in contaminant-exposed English sole.
Comparison of PCB and trace metal bioaccumulation in the blue mussel, Mytilus edulis, and the ribbed mussel, Modiolus demissus, in new Bedford Harbor, Massachusetts
Authors: Nelson William G. , Bergen Barbara J. , Cobb Donald J. 
Published: March 2010

Abstract
The accumulation of PCBs and trace metals was compared at 14-d intervals between two filter-feeding bivalves, the blue mussel, Mytilus edulis, and the ribbed mussel, Modiolus demissus, after deployment in New Bedford Harbor, Massachusetts, for up to 56 d. Contaminant uptake in deployed organisms also was compared with indigenous ribbed mussels. Significant mortality (&gt;80%) occurred in blue mussels after 28 d, when water temperatures exceeded 25°C. Therefore, tissue-residue comparisons between species are presented only up to day 28, while those between deployed and indigenous ribbed mussels continue to day 56. Results indicated that total PCB tissue residues and congener distributions were not statistically different (p &gt; 0.05) in the two mussel species on day 28. Total PCB concentrations in both deployed mussel species reached approximately 30 μg g−1 dry weight by day 28. Additionally, total PCB concentrations and congener distributions in the deployed ribbed mussels were not statistically different from the indigenous ribbed mussels on day 28, demonstrating that steady state was attained within 28 d. With respect to metal uptake, no single accumulation pattern occurred for the eight metals quantified. After 28 d, lead, cadmium, and iron concentrations in deployed blue and ribbed mussels were statistically similar. However, nickel and zinc accumulations were significantly greater in the blue mussels, and copper, chromium, and manganese were accumulated to significantly higher concentrations in the ribbed mussels. The comparison between the ribbed mussels indicated that cadmium and lead concentrations were significantly higher in indigenous than in deployed mussels after 28 d.
Effects of simulated chlorsulfuron drift on fruit yield and quality of sweet cherries (Prunus avium L.)
Authors: Bhatti Muhammad A. , Felsot Allan S , Al-Khatib Kassim , Kadir Sorkle , Parker Robert 
Published: March 2010

Abstract
Field experiments were conducted at the Irrigated Agricultural Research and Extension Center, Prosser, Washington, in 1992 and 1993 to study the effects of simulated chlorsulfuron (2 chloro-N [[(4 methoxy-6 methyl 1,3,5-tnazin 2 yl)amino]-carbonyl]benzenesulfonamide) drift at different reproductive growth stages of three cherry (Prunus avium L ) cultivars, Rainier, Chinook, and Bing Branches of each cultivar were treated at side-green, full bloom, postbloom, and pit hardening growth stages with 0, 251 1 × 10 7, 83 8 × 10 7, 27 9 × 10−7, 9 3 × 10−7, and 3 1 × 10−7 M chlorsulfuron In single-exposure expetiments, Chinook was adversely affected by the lower levels of chlorsulfuron Bing was not affected by levels of chlorsulfuron below 27 9 × 10 7 M The yield and quality of fruit decreased significantly with the increase in chlorsulfuron concentrations applied at full bloom and postbloom stages Reduction in yield was correlated with the severity of injury symptoms on leaves In the multiple exposure experiments, fruit yield, fruit size, and color were significantly reduced by increasing chlorsulfuron concentration and number of exposures Average firmness of fruit increased with increases in chlorsulfuron concentration The data suggested that multiple exposures of a susceptible cherry cultivar to low levels of chlorsulfuron at full bloom and postbloom stage can reduce fruit yield and delay maturity of cherries while increasing fruit firmness
The influence of multiple sewage sludge amendments on the PCB content of an agricultural soil over time
Authors: Alcock R. E. , McGrath S. P. , Jones K. C. 
Published: March 2010

Abstract
The polychlorinated biphenyl (PCB) content of soils from a long-term agricultural experiment that received 25 separate sewage sludge applications from 1942 to 1961 is presented, along with data from an untreated control plot. Archived plough layer (0 to 23 cm) soil samples were collected, stored, and processed in the same manner between 1942 and 1992 (i.e., before, during, and after sludge amendments) and samples of the applied sludges were available for analysis. Soil Σ PCB concentrations (defined as the sum of the 27 congeners quantified) on the control plot increased between 1942 (63 μg Σ PCB kg−1 and 1972 (560 μg Σ PCB kg−1) as a result of atmospheric deposition inputs; they subsequently declined to 13 μg Σ PCB kg−1 in 1992. A total of ˜ 1 kg Σ PCBs/hectare was applied in sewage sludges (containing 0.14 to 4.33 mg Σ PCB kg−1) to the sludge-amended plot. Soil concentrations increased accordingly, to 640 μg Σ PCB kg−1 by 1960. However, because of the continued high atmospheric deposition inputs, concentrations on this plot also continued to increase until 1972. By 1992, the sludge-amended plot contained ca. 5 times the Σ PCB content of the control plot. By 1960, ˜81% of the predicted Σ PCB added in sludge could be accounted for; this had decrease to &lt;50 and 21% by 1984 and 1992, respectively. Marked compound-specific differences in soil persistence were noted; generally lower chlorinated (3/4-Cl) congeners became less important contributors to the Σ PCB content of the soils over time, while 5-Cl homologues and above increased.