bluuebunny/crossref_metadata_2025_split huggingface dataset:
Linking insecticide contamination and population response in an agricultural stream
Authors: Liess Mathias , Schulz Ralf 
Published: March 2010

Abstract
The study aims to evaluate the impact of insecticides associated with rainfall-induced surface runoff from arable land on macroinvertebrate populations. These effects of insecticides were distinguished from the hydraulic stress also associated with surface runoff. Transient increase in discharge and insecticide contamination (maximum 6 μg/L parathion-ethyl in stream water, 302 μg/L fenvalerate in suspended particulates) was observed in a headwater stream subsequent to surface runoff from arable land. In the aquatic macroinvertebrate community, eight of the eleven abundant species disappeared, and the remaining three were reduced significantly in abundance following the insecticide-contaminated runoff. Recovery within 6 months was observed for four species and recovery within 11 months for nine species. Two species remained at a low population density for over a year. The effects of insecticides were distinguished from other parameters, such as hydraulic stress associated with surface runoff, as well. The causal connection between insecticide contamination and biological response was established by eliminating increased hydraulic stress during surface runoff using in-parallel bypass microcosms containing the dominant species Gammarus pulex and Limnephilus lunatus. The mortality of these species was similar to that of the same species in the stream. Additional microcosms, disconnected from the stream during runoff events, served as a control. Thus, the toxic potential of the runoff water is considered to be responsible for the observed effect on the macroinvertebrates. It is concluded that agricultural insecticide input may alter the dynamics of macroinvertebrate communities in streams.
Differences in neurobehavioral responses of chinook salmon (Oncorhynchus tshawytscha) and rainbow trout (Oncorhynchus mykiss) exposed to copper and cobalt: Behavioral avoidance
Authors: Hansen James A , Marr John C A , Lipton Joshua , Cacela Dave , Bergman Harold L 
Published: March 2010

Abstract
Behavioral avoidance of copper (Cu), cobalt (Co), and a Cu and Co mixture in soft water differed greatly between rainbow trout (Oncorhynchus mykiss) and chinook salmon (O. tshawytscha). Chinook salmon avoided at least 0.7 μg Cu/L, 24 μg Co/L, and the mixture of 1.0 μg Cu/L and 0.9 μg Co/L, whereas rainbow trout avoided at least 1.6 μg Cu/L, 180 μg Co/L, and the mixture of 2.6 μg Cu/L and 2.4 μg Co/L. Chinook salmon were also more sensitive to the toxic effects of Cu in that they failed to avoid ≤44 μg Cu/L, whereas rainbow trout failed to avoid ≤180 μg Cu/L. Furthermore, following acclimation to 2 μg Cu/L, rainbow trout avoided 4 μg Cu/L and preferred clean water, but chinook salmon failed to avoid any Cu concentrations and did not prefer clean water. The failure to avoid high concentrations of metals by both species suggests that the sensory mechanism responsible for avoidance responses was impaired. Exposure to Cu concentrations that were not avoided could result in lethality from prolonged Cu exposure or in impairment of sensory-dependent behaviors that are essential for survival and reproduction.
Chinook salmon (Oncorhynchus tshawytscha) and rainbow trout (Oncorhynchus mykiss) exposed to copper: Neurophysiological and histological effects on the olfactory system
Authors: Hansen James A , Rose James D , Jenkins Robert A , Gerow Kenneth G , Bergman Harold L 
Published: March 2010

Abstract
Olfactory epithelial structure and olfactory bulb neurophysiological responses were measured in chinook salmon and rainbow trout in response to 25 to 300 μg copper (Cu)/L. Using confocal laser scanning microscopy, the number of olfactory receptors was significantly reduced in chinook salmon exposed to ≥0 μg Cu/L and in rainbow trout exposed to ≥200 μg Cu/L for 1 h. The number of receptors was significantly reduced in both species following exposure to 25 μg Cu/L for 4 h. Transmission electron microscopy of olfactory epithelial tissue indicated that the loss of receptors was from cellular necrosis. Olfactory bulb electroencephalogram (EEG) responses to 10−3 M L-serine were initially reduced by all Cu concentrations but were virtually eliminated in chinook salmon exposed to ≥50 μg Cu/L and in rainbow trout exposed to ≥200 μg Cu/L within 1 h of exposure. Following Cu exposure, EEG response recovery rates were slower in fish exposed to higher Cu concentrations. The higher sensitivity of the chinook salmon olfactory system to Cu-induced histological damage and neurophysiological impairment parallels the relative species sensitivity observed in behavioral avoidance experiments. This difference in species sensitivity may reduce the survival and reproductive potential of chinook salmon compared with that of rainbow trout in Cu-contaminated waters.
Metal toxicity in two rodent species and redox potential: Evaluation of quantitative structure—activity relationships
Authors: Lewis, David FV , Dobrota Miloslav , Taylor Marina G , Parke Dennis V 
Published: March 2010

Abstract
A quantitative structure—activity relationship study of acute toxicity in the mouse and rat is described for the soluble salts of a relatively large number of metals (between 25 and 30 in total). Electrode potential is the major determinant of acute metal toxicity (R = 0.85 and 0.86) for an intraperitoneal dose in the mouse, whereas the addition of ionic radius and polarizability enables the inclusion of notable outliers in the original expression, such as beryllium and barium, thus giving a good correlation (R = 0.87) with toxicity for 27 metal compounds. These findings are rationalized on the basis of relative ease of ionization, electron affinity, and transport factors of the metals and their ions, thus being consistent with the hard and soft acids and bases properties of metals and their biological reactivities.
Decolorization of olive oil mill wastewaters by Phanerochaete flavido-alba
Authors: Hamman Omar Ben , de la Rubia Teresa , Martínez José 
Published: March 2010

Abstract
Olive oil mill wastewater (OMW), a major waste product of olive oil extraction, contains many recalcitrant compounds, mainly present in the colored fraction. In this study we attempted to identify optimum culture conditions for the decolorization of OMW by Phanerochaete flavido-alba for subsequent use in bioremediation assays. Of several media tested, nitrogen-limited P. flavido-alba cultures containing 40 mg/L Mn(II) were the most efficient at decolorizing OMW. Decolorization was accompanied by a 90% decrease in the OMW phenolic content. Concentrated extracellular fluids alone (showing manganese peroxidase, but not lignin peroxidase activity) did not decolorize the major OMW pigment, suggesting that mycelium binding forms part of the decolorization process.
Relative sensitivity of marine species to an effluent with elevated total dissolved solids
Authors: Kline Edward R , Stekoll Michael S 
Published: March 2010

AbstractThe acute toxicity of aged gold mill effluent was compared for two reference species (juvenile mysid shrimp [Mysidopsis bahia (Americamysis bahia)] and larval sheepshead minnows [Cyprinodon variegatus]) and larvae of three species that are indigenous to the southern coast of Alaska (red king crab [Paralithodes camtschaticus], northern shrimp [Pandalus borealis], and Pacific herring [Clupea harengus pallasi]). Effluent osmolality was equivalent to that of 12 ppt seawater. Concentration–response relationships for the effluent, adjusted to equal the osmolality and pH of 31 ppt seawater, were determined after 24 h of exposure for immobility, paralysis, and death. The magnitude of differences and rank of sensitivity of the indigenous species depended on the response that was used for the comparison. For all responses, M. bahia and C. variegatus were the most and least sensitive species, respectively.
Comparative toxicity and toxicokinetics of ddt and its major metabolites in freshwater amphipods
Authors: Lotufo Guilherme R , Landrum Peter F , Gedeon Michelle L , Tigue Elizabeth A , Herche Lynn R 
Published: March 2010

Abstract
The toxicity and toxicokinetics of radiolabeled DDT and its major degradation products, dichlorodiphenyldichloroethane (DDD) and dichlorodiphenyldichloroethylene (DDE), were determined for the amphipods Hyalella azteca and Diporeia spp. in water-only static renewal exposures. Comparison of the water and tissue concentrations associated with decreased survival revealed large differences in toxicity among the three compounds. In H. azteca, the ratio of the 10-d LR50 values (median lethal tissue residue) for DDT:DDD:DDE was 1:24:195. In Diporeia spp., the 28-d LR50 for DDT was higher than that for DDD by a factor of six, and DDE did not cause significant mortality even at concentrations approaching the solubility limit. Based on the toxicity data, the hazard from exposure to mixtures of DDT and its degradation products should be evaluated on a toxic-units basis and not as a simple summation of the individual concentrations, which ignores the toxicity of specific compounds. Differences in species sensitivity were also detected. The 10-d LR50 values were higher in Diporeia spp. than in H. azteca by a factor of 40 for DDT and eight for DDD. This difference can be only partly attributed to differences in lipid content between H. azteca (7% dry wt) and Diporeia spp. (24% dry wt). The uptake clearance and elimination rate constants were similar among the various compounds in both species. Uptake clearance was typically fourfold greater for H. azteca than for Diporeia spp., however, and the experimentally measured elimination rate was approximately 30-fold greater in H. azteca than in Diporeia spp. The larger rates of uptake and elimination were attributed to the higher exposure temperature, greater surface area-to-volume ratio, and lower lipid content for H. azteca compared with Diporeia spp. In addition, extensive biotransformation of DDT by H. azteca may have contributed to a more rapid compound elimination.
Bioaccumulation patterns of polychlorinated biphenyls and chlorinated pesticides in Northwest Atlantic pilot whales
Authors: Weisbrod Anne V. , Shea Damian , Moore Michael J , Stegeman John J 
Published: March 2010

Abstract
Contaminant exposure is widespread among marine mammals but is of unknown significance. This study characterized organochlorine bioaccumulation in pilot whales, and these bioaccumulation patterns are proposed as representative of Northwest (NW) Atlantic cetacea. Samples were collected from whales stranded in Massachusetts and caught in nets. Polychlorinated biphenyl (PCB) and chlorinated pesticide concentrations were determined via GC/ECD and found to be similar to those reported for other NW Atlantic odontocetes. The organochlorine in highest concentration was 4,4′-DDE, followed by trans-nonachlor, 4,4′-DDD, dieldrin, cis-chlordane, Cl4(52), Cl5(95), Cl5(101), Cl5(118), Cl6(138), Cl6(149), Cl6(153), Cl7(180), and Cl7(187). The concentration of 19 pesticides was higher in blubber (21 ± 26 μg/g lipid “ppm”) than liver (5.0 ± 7.1 ppm). The concentration of 26 PCB congeners was also greater in blubber (7.6 ±7.1 ppm) than liver (0.4 ± 7.3 ppm). Principal component analysis and ANOVA indicated that blubber accumulated proportionately more of the most recalcitrant compounds, such as 4,4′-DDE and nonmetabolizable PCBs, compared to liver. Whales that stranded together had more similar bioaccumulation than animals of the same gender or maturity. The high variation among individuals in tissue concentrations and the similarity within a stranding group suggest that pilot whale pods are exposed to a large range of pollutant sources, such as through different prey and feeding locations.
Community-level responses by stream insects to neem products containing azadirachtin
Authors: Kreutzweiser David P , Capell Scott S , Scarr Taylor A 
Published: March 2010

Abstract
Outdoors sream channels weret teated with a commercial neem formulation, Neemixx® 4.5, and a neem extract (no formulation ingredients) to determine the effects on aquatic insect communities. An exposure period of 5 h was chosen to simulate the transient nature of pesticide residues in streams and rivers after aerial applications. Multivariate analytic procedures based on Bray-Curtis similarity matrices were used to compare community structure among the replicate channels 9 d after treatment. No significant differences in community structure were found among controls and channels treated with Neemix at an azadirachtin concentration of 0.28 mg/L, but a multivariate measure of community stress indicated an increase in variability among treated channels. Significant differences in community structure were found among controls and channels treated with Neemix at 0.84 and 2.54 mg/L, and this resulted from reductions in several key taxa. During subsequent experiments with a neem powder extract, the formulation ingredients of Neemix were at least partially responsible for the significant effects on community structure at 0.84 mg/L azadirachtin. No significant differences were found among controls and channels treated with the extract at 0.9 mg/L, whereas the community structure of aquatic insects in channels treated at 3.0 mg/L differed significantly from controls. In a Canadian forest pest-management context, the expected environmental concentration in water bodies of areas sprayed with azadirachtin at 50 g/ha is 0.035 mg/L.
Whole-lake burdens and spatial distribution of cadmium in sediments of Wisconsin seepage lakes, USA
Authors: Powell David E. , Rada Ronald G , Wiener James G , Atchison Gary J 
Published: March 2010

AbstractCadmium was quantified in the surface sediments of six seepage lakes ranging from 8 to 70 ha in surface area, 6 to 20 m in maximum depth, 5.2 to 7.0 in mean epilimnetic pH, and 1.7 to 6.8 mg·L−1 in dissolved organic carbon. Within each lake, dry-weight concentrations of cadmium (range, 0.02–7.17 μg·g−1) were positively correlated with volatile matter content of the sediments, which increased with water depth. Volumetric concentrations (i.e., mass per volume of wet sediment) were correlated with water depth in only one lake, and they more accurately represented the spatial distribution of sedimentary cadmium within the lakes. Analysis of sediment cores from two of the lakes indicated that surface sediments were enriched with cadmium. The source of cadmium and the within-lake processes controlling deposition to the sediments were presumably similar among the lakes, as demonstrated by the strong correlation between lake area and whole-lake burdens of cadmium in the surface sediments (range, 625–5785 g/lake). Hence, cadmium in these lakes appears to be derived largely from atmospheric deposition. When normalized for lake area, cadmium burdens in the surface sediments ranged from 62 to 92 g·ha−1 and were strongly correlated with dissolved organic carbon, but not with lake pH, which suggests a link between the transport of cadmium and organic matter to the sediments.
Acute toxicity of storm water associated with de-icing/anti-icing activities at Canadian airports
Authors: Novak Lesley J , Holtze Keith , Kent Robert A , Jefferson Catherine , Anderson Don 
Published: March 2010

AbstractEnvironment Canada, Transport Canada, and the Airline Transport Association of Canada recently evaluated the use of toxicity bioassays to assist in managing wastewater from aircraft de-icing at Canadian airports. This study evaluated the effectiveness of a suite of rapid screening bioassays to predict the responses of standard regulatory test organisms to storm water associated with de-icing at four Canadian airports. Storm water samples were tested using two standard acute lethality bioassays (rainbow trout [Oncorhynchus mykiss], Daphnia magna) and four rapid screening bioassays (Daphnia IQ™, acute Microtox®, Rotoxkit®, Thamnotoxkit®). Environmental samples (runoff water) and concentrated de-icing/anti-icing chemicals from the clean-up vehicles (sweeper trucks) were collected from each airport and tested. Forty percent (n = 10) of the environmental samples were lethal to trout, and 30% were lethal to D. magna. The IQ and Thamnotoxkit test results were comparable to those of the trout and daphnid bioassays, respectively. Disadvantages associated with the IQ and Thamnotoxkit bioassays included the lack of a standardized quality-assurance/quality-control program, subjectivity in endpoint measurements, and problems in cyst hatching. The limited number of storm-related samples did not permit definitive determination for the causality of toxicity. Results suggest that glycol was not predictive of acute lethality, and that other substances likely contributed to toxicity.
Effects of endocrine-active chemicals on the development of sex characteristics of Daphnia magna
Authors: Olmstead Allen W , LeBlanc Gerald A 
Published: March 2010

Abstract
Standard reproductive assays with daphnids involve parthenogenetically reproducing females and exclude the assessment of effects on sexual reproduction. The goals of this study were to characterize sexual differentiation of male and female daphnids (Daphnia magna) and to evaluate whether exposure to putative endocrine-disrupting chemicals may perturb the development of sex characteristics. Anatomical sex differences that developed during maturation in males included elongated first antennae and morphologic alterations in the head capsule and carapace edge. Reproductive maturation in females was associated with the development of a brood chamber and abdominal process. Alterations in the growth rates of the first antennae of males and the abdominal process of females were used to evaluate the effects of chemical exposure on the development of these sex characteristics during maturation. Exposure of female daphnids to the nonsteroidal vertebrate estrogen diethylstilbesterol and the insect juvenile hormone analog methoprene at concentrations as low as 3.0 and 0.080 μM, respectively, stimulated development of the abdominal process. Exposure of males to the steroidal vertebrate androgen androstenedione (≥6.0 μM) stimulated development of the first antennae. These results demonstrate that the development of secondary sex characteristics in daphnids can be altered by chemical exposure.
Test of Σ polycyclic aromatic hydrocarbon model at a creosote-contaminated site, Elliott Bay, Washington, USA
Authors: Ozretich Robert J , Ferraro Steven P , Lamberson Janet O , Cole Faith A 
Published: March 2010

Abstract
At a creosote-contaminated site, 33 individual polycyclic aromatic hydrocarbon (PAH) compounds were quantified in sediment and interstitial water (IW) at 30 stations. These compounds included the 13 parent PAHs from the ΣPAH model, 7 additional parent, and 13 alkylated compounds. Fourteen groups of alkylated compounds were also quantified in sediment extracts. Amphipod mortality using the ΣPAH model was predicted within ±10% of the observed when freely dissolved concentrations of PAHs with log Kows &lt; 6.0 were used in the calculation of toxic units (TUs). The TUs computed from bulk sediment tended to overestimate the observed distribution of mortality. Although present, alkylated PAHs did not contribute significantly to the observed toxicity that was dominated by parent PAHs. The dominant parent compounds were in equilibrium with the interstitial water and sediment at the most contaminated stations (&gt;500 ppm dry). However, most compounds were not in equilibrium with the sediment at stations with lower bulk concentrations but were in equilibrium with dissolved organic matter throughout the study area.
In vitro and in vivo association of 2,3,7,8-tetrachlorodibenzo-p-dioxin and benzo[a]pyrene with the yolk-precursor protein vitellogenin
Authors: Monteverdi George H , Giulio Richard T. Di 
Published: March 2010

Abstract
These studies investigated the association ofcommon environmental contaminants 2,3,7,8-tetraclorodibenzo- p-dioxin (TCDD) and benzo[a]pyrene (B[a]P) with the yolk-precursor protein vitellogenin (VTG). In vitro studies with purified VTG from the channel catfish (Ictaluruspunctatus) demonstrated that 3H-TCDD and 3H- B[a]P associated with VTG in a nonsaturable manner. The magnitude of this association (i.e., pmoles of radioligand/mg VTG) increased with increasing chemical concentrations until the point of chemical insolubility in the incubation medium. In vivo, time-course experiments with gravid female mummichogs (Fundulus heteroclitus) exposed to either 3H-TCDD or 14C-B[a]P revealed time- and dose-dependent changes in total serum radiochemical content. In sera from female F. heteroclitus exposed to either chemical, &gt;80%of detected radioactivity was associated with VTG and a second chromatographic peak, a lipoprotein fraction putatively identified as high-density lipoproteins. In experiments comparing radiochemical serum compartmentalization in estrogenized (E2+) versus control male fish, the presence of VTG in E2 + males significantly altered the overall quantity and profile of serum protein-associated radiochemical. In these experiments, serum VTG was present in very large quantities (40-50% of total serum protein) and the majority (62-81% for 3H-TCDD; 56-71% for 14C-B[a]P) of radiolabeled ligand was associated with VTG. The structure of the VTG protein, combined with the apparently nonsaturable nature of the association between VTG and these lipophilic compounds, suggests a VTG-ligand association that is both nonspecific and of significant capacity. Given the central role of VTG in egg production and early-life development, these findings suggest a significant role for VTG as a vector of xenobiotic maternal transfer. This role is further supported by companion studies (this volume) that examined oocyte accumulation of TCDD and B[a]P.
Dose-dependent growth inhibition and bioaccumulation of hexavalent chromium in land snail Helix aspersa aspersa
Authors: Cœurdassier Michaël , Vaufleury Annette Gomotde , Badot Pierre-Marie 
Published: March 2010

Abstract
The toxicity of Cr6+ was determined in a laboratory environment in the snail Helix aspersa aspersa. The effects on growth were evaluated on animals reared in controlled conditions at the age of one month that had been exposed for 28 d to increasing doses of Cr6+ mixed in with their food. Two experimental groups were set up with concentrations of chromium in the feed of 250 to 1,250 μg/g (test 1) and 100 to 800 μg/g (test 2). Growth inhibition was dose dependent, and the mean EC50 calculated at four weeks for tests 1 and 2 were, respectively, 354.7 and 298.8 μg/g and for the EC10 195.3 and 160.9 μg/g. The levels of Cr6+ bioaccumulated in the foot and the viscera of the snails were dose dependent in both types of tissues. The highest concentrations occurred in the viscera, the levels being 0.79 μg/g in the controls and reaching 3,067 μg/g in the animals exposed to the maximum contamination (1,250 μg/g). These high levels of bioaccumulation in addition to the lower concentrations of Cr6+ excreted in the feces than those present in the food suggest that chromium is not physiologically regulated by Helix aspersa. The results provide added support for the use of snails as a model to determine the toxicity of substances in laboratory biotests by measuring the effects on growth and by assessing bioaccumulation.