bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of complexation with chloride on the responses of a lux-marked bacteria bioassay to cadmium, copper, lead, and mercury
Authors: Sarin Charoon , Hall Jennifer M , Cotter-Howells Janet , Killham Ken , Cresser Malcolm S 
Published: March 2010

Abstract
The toxicity of a heavy metal in solution to a microorganism depends not only on its concentration but also on pH and the concentrations of any aqueous complexing ligands in the microorganism's environment. This paper reports on the use of different inorganic resuscitation media and effect of the chloride ion, Cl−, on the bioluminescence response of a bacterial biosensor, Escherichia coli HB101 (pUCD607), to four metals: Cd, Cu, Hg, and Pb. The toxicity tests were conducted at pH 4, using 0.1 M KNO3 as resuscitation medium and adding KCl to investigate effect of Cl− concentration. The species distributions of metals as a function of Cl− concentration were calculated using GeoChem-PC. Resuscitation in 0.1 M KC1 gave significantly higher light output than that in 0.1 M KNO3, demonstrating that Cl− in the resuscitation medium has a direct effect on the bioluminescence response of the E. coli biosensor. Increasing concentrations of Cl− ions increased the toxicity of Hg, apparently because of the formation of HgCl−3, and increased the toxicity of Pb because of PbCl+ formation. The toxicity of Cu decreased at high Cl− concentrations as free Cu2+ decreased, in accordance with the free ion model. Concentrations of Cl− had no significant effect on the toxicity of Cd. This study clearly demonstrates that the chloro-complexes of some heavy metals can be toxic and, for Pb and Hg, more toxic than the free ion.
Correlating environmental partitioning properties of organic compounds: The three solubility approach
Authors: Cole John G , Mackay Donald 
Published: March 2010

Abstract
It is suggested that in addition to correlating the environmental partitioning characteristics of chemicals as partition coefficients, it is also valuable to correlate them as solubilities or pseudo-solubilities. These solubilities are essentially convenient, readily understood, and in many cases, measurable expressions of single-phase activity coefficients. To illustrate this approach, a novel, three solubility, quantitative structure-property relationships (or QSAR) approach is described for correlating the physico-chemical parameters in which the solubilities or pseudo-solubilities of individual chemicals in the liquid or super-cooled liquid state, both individually and as homologous series, are compiled and correlated as a function of temperature in the three primary media of air, water, and octanol and possibly in other relevant media. These quantities, which are deduced from measured partition coefficients, solubilities, and vapor pressures, comprise a consistent data set that can be used to estimate a variety of environmentally relevant partition coefficients. The approach is demonstrated in detail for the chlorobenzenes and in a preliminary fashion for a variety of persistent and hydrophobic substances. The merits of this approach as a supplement to the conventional use of partition coefficients are discussed.
Toxic responses of medaka, D-rR strain, to polychlorinatednaphthalene mixtures after embryonic exposure by in ovo nanoinjection: A partial life-cycle assessment
Authors: Villalobos Sergio A , Papoulias Diana M , Meadows John , Blankenship Alan L , Pastva Stephanie D , Kannan Kurunthachalam , Hinton David E , Tillitt Donald E , Giesy John P 
Published: March 2010

Abstract
Polychlorinated naphthalenes (PCNs) are organic compounds with some chemical properties and uses similar to polychlo-rinated biphenyls. Polychlorinated naphthalenes have been detected in biota from certain aquatic environments. The toxicities of several PCN technical mixtures (Halowax) to medaka (Oryzias latipes) were determined by use of an embryo nanoinjection method. Medaka eggs (early gastrula) were injected with 0.5 nl of triolein (vehicle control) or 0.5 nl of four to five graded doses (0.3–30 ng/egg) of Halowax 1014, Halowax 1013, or Halowax 1051 in triolein. Following exposure, embryos developed, and fry were reared to sexual maturity (4 months), at which time they were euthanized. Responses were evaluated as early life stage (ELS) and early adult life stage (EALS) assessments. For ELS, lethality and sublethal alterations in embryos and larvae (&lt;16 d old), such as craniofacial, cardiovascular, and myoskeletal deformities and abnormal or delayed hatch, were monitored for the first 9 d, and a dose severity index was computed. The EALS assessment examined the survival of 16-d-old larvae until early adulthood (123 ± 3 d old), including gonadosomatic index (GSI) and morphometry. Halowax 1014 was found to be the most toxic mixture (LD50 4.2 ng/egg), whereas Halowax 1013 and 1051 were significantly less toxic (LD50s could not be determined). The gonadosomatic index of females was significantly less in fish dosed with Halowax 1014 or 1051. The LD50 for medaka embryos nanoinjected with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is about 0.75 pg/egg. Thus, Halowax 1014 was 5,585-fold less potent than TCDD. For Halowax 1014, ELS assessments accurately predicted the results of EALS assessments.
Biochemical and developmental effects of dietary exposure to polychlorinated biphenyls 126 and 153 in common tern chicks (Sterna hirundo)
Authors: Bosveld Albertus T. C. , Nieboer Ruud , de Bont Alex , Mennen Judith , Murk Albertinka J , Feyk Lori A , Giesy John P , van den Berg Martin 
Published: March 2010

AbstractEffects of PCBs weres studied in common terns (Sterna hirundo). Hatchlings from eggs collected from Dutch breeding colonies and incubated artificially were raised to an age of 21 d. The birds were fed fish spiked with PCB 126 alone or in combination with PCB 153 (1:1,000), resulting in concentrations in the food ranging from 0.01 to 1.2 ng toxic equivalents (TEQs)/g wet weight. The most sensitive effect parameter was induction of hepatic CYP1A-associated ethoxyresorufin-O-deethylation (EROD) activity, and a nonlinear concentration–effect relationship could be determined with the TEQ concentration (r = 0.967, p &lt; 0.001). Induction of pentoxyresorufin-O-depenthylation and methoxyresorufin-O-demethylation activities was observed at dose levels similar to those that induced EROD activity. The estimated lowest-observed-effect level for induction of CYP1A in the common tern was approx. 25 ng TEQ/g liver lipid, which was caused by concentrations in the food of approx. 0.6 ng TEQ/g fish wet weight. At these concentrations, a 50% reduction in plasma total thyroxine compared with controls also was observed. Concentrations of plasma total thyroxine were negatively correlated with hepatic TEQ concentrations (r = 0.523, p &lt; 0.01), but the shape of the nonlinear concentration–effect relationship did not allow determination of a lowest-observed-effect level. No changes were found for hepatic hydroxylation of testosterone. Bursa weight decreased proportionally to hepatic concentrations of TEQs (r = 0.433, p &lt; 0.05) and showed a similar sensitivity as that observed for EROD activity. Concentrations of TEQs in The Netherlands are approx. 0.1 ng TEQ/g wet weight fish, which is approximately six times lower than the lowest-observed-effect level for CYP1A induction in terns as estimated in this study. It is concluded that no overt effects on growth and development in the common tern are expected with this background exposure during the posthatch period.
Seasonal concentrations of organic contaminants at the fall line of the Susquehanna River basin and estimated fluxes to northern Chesapeake Bay, USA
Authors: Foster Gregory D , Lippa Katrice A , Miller Cherie V 
Published: March 2010

Abstract
Riverine fluxes of several pesticides and other organic contaminants from above the fall line of the Susquehanna River basin to northern Chesapeake Bay, USA, were quantified in 1994. Base flow and storm flow samples collected at the fall line of the river from February to December 1994 were analyzed for both dissolved and particulate phase contaminants. Measured concentrations of the organonitrogen and organophosphorus pesticides varied mainly in response to the timing of their application to agricultural fields. Conversely, the concentrations of the more particle-sorptive contaminants such as polychlorinated biphenyls (PCBs), organochlorine (OC) insecticides, and polycyclic aromatic hydrocarbons (PAHs) were more directly correlated with river flow throughout the year. Annual fluxes were almost entirely in the dissolved phase for the organonitrogen and organophosphorus pesticides, distributed between the dissolved and particulate phases for the PCBs and OC insecticides, and primarily in the particulate phase for the PAHs.
Development and evaluation of consensus-based sediment effect concentrations for polychlorinated biphenyls
Authors: MacDonald Donald D , Dipinto Lisa M , Field Jay , Ingersoll Christopher G , Lvong Edward R , Swartz Richard C 
Published: March 2010

Abstract
Sediment-quality guidelines (SQGs) have been published for polychlorinated biphenyls (PCBs) using both empirical and theoretical approaches. Empirically based guidelines have been developed using the screening-level concentration, effects range, effects level, and apparent effects threshold approaches. Theoretically based guidelines have been developed using the equilibrium-partitioning approach. Empirically-based guidelines were classified into three general categories, in accordance with their original narrative intents, and used to develop three consensus-based sediment effect concentrations (SECs) for total PCBs (tPCBs), including a threshold effect concentration, a midrange effect concentration, and an extreme effect concentration. Consensus-based SECs were derived because they estimate the central tendency of the published SQGs and, thus, reconcile the guidance values that have been derived using various approaches. Initially, consensus-based SECs for tPCBs were developed separately for freshwater sediments and for marine and estuarine sediments. Because the respective SECs were statistically similar, the underlying SQGs were subsequently merged and used to formulate more generally applicable SECs. The three consensus-based SECs were then evaluated for reliability using matching sediment chemistry and toxicity data from field studies, dose-response data from spiked-sediment toxicity tests, and SQGs derived from the equilibrium-partitioning approach. The results of this evaluation demonstrated that the consensus-based SECs can accurately predict both the presence and absence of toxicity in field-collected sediments. Importantly, the incidence of toxicity increases incrementally with increasing concentrations of tPCBs. Moreover, the consensus-based SECs are comparable to the chronic toxicity thresholds that have been estimated from dose-response data and equilibrium-partitioning models. Therefore, consensus-based SECs provide a unifying synthesis of existing SQGs, reflect causal rather than correlative effects, and accurately predict sediment toxicity in PCB-contaminated sediments.
Importance of contamination history for understanding toxicity of copper to earthworm Eisenia fetica (Oligochaeta: Annelida), using neutral-red retention assay
Authors: Scott-Fordsmand Janeck J , Weeks Jason M , Hopkin Stephen P 
Published: March 2010

Abstract
Eisenia fetida was exposed in the laboratory to a range of elevated soil copper (Cu) concentrations under two different contamination histories. An EC10 for reproduction was observed at 34 mg Cu/kg for soil spiked with Cu 1 d prior to running the experiment (newly spiked soil). Soil contaminated with Cu in the field more than 70 years previously (field-contaminated soil) caused a 10% decrease in reproduction at 248 mg Cu/kg. Survival and cocoon wet weights were not affected by soil concentrations up to 1,400 mg Cu/kg under either contamination history. Adult growth was reduced at 428 mg Cu/kg (EC10) in newly spiked soil but not in field-contaminated soil at concentrations up to 1,400 mg Cu/kg. The contamination history, as well as the toxicological parameter, was important in the interpretation of the outcome of a standard laboratory toxicity test. The lysosomal membrane stability of coelomocytes, measured as neutral-red retention time (NRR-time), was reduced at soil Cu concentrations lower than those affecting reproduction and demonstrated a dose–response relationship. The NRR-time was more severely reduced in worms exposed to newly Cu-spiked soil (EC10 = 8 mg Cu/kg) than worms exposed to field-contaminated soil (EC10 = 69 mg Cu/kg). The NRR-time reflected the bioactive Cu fraction, showing a good correlation with reproduction under both contamination histories.
A study of the structure and metal tolerance of the soil microbial community six years after cessation of sewage sludge applications
Authors: Witter Ernst , Gong Ping , Bååth Erland , Marstorp Håkan 
Published: March 2010

AbstractChanges in soil microbial community structure and development of metal tolerance as a result of past applications of unamended sewage sludge and metal-amended sewage sludge were found in soils of a long-term field experiment at Braunschweig, Germany. Both the rate of sewage sludge application and metal amendment affected the size and activity of the microbial biomass and had caused changes in microbial community structure as seen by differences in phospholipid fatty acid (PLFA) profiles. Past sewage sludge additions and metal amendment had an effect on the microbial respiratory response to 15 different C substrates, but both the magnitude and the direction of this response were substrate dependent. Differences between the soils in the respiratory response to the substrates were therefore probably largely determined by differences in the composition of the microbial consortia utilizing the substrates. The level of metal tolerance of the soil bacterial community determined by the thymidine incorporation technique and that of the microbial consortium growing on glucose in situ (determined from respiration measurements) increased with the level of metal contamination of the soil. Metal tolerance measurements could identify the metal with the largest toxicity effect in this experiment with multiple metal-polluted sewage sludge.
Inhibition of methanogenesis by C1- and C2-polychlorinated aliphatic hydrocarbons
Authors: Yu Zhongtang , Smith Geoffrey B 
Published: March 2010

Abstract
Inhibition of methanogenesis in ananaerobic wastewater digester sample by four common polychlorinated aliphatic hydrocarbons (dichloromethane, chloroform, trichloroethylene, and perchloroethylene) was investigated. Chloroform was shown to be the most inhibitory, and an aqueous concentration of chloroform as low as 0.09 mg/L completely inhibited methanogenesis. Dichloromethane inhibited methanogenesis at 3.9 mg/L, trichloroethylene at 18 mg/L, but 14.5 mg/L of perchloroethylene did not inhibit methanogenesis. The following order of inhibition was determined (in descending potencies): chloroform ≫ dichloromethane &gt; trichloroethylene &gt; perchloroethylene. The wastewater consortium dechlorinated chloroform, trichloroethylene, and perchloroethylene but not dichloromethane. Our results suggest that inhibition of methanogenesis and dechlorination is determined by both the extent of chlorination and the molecular structure of polychlorinated hydrocarbons. A model is presented, proposing that polychlorinated hydrocarbons inhibit methanogenesis directly and/or indirectly by binding to corrinoid/porphinoid enzymes and free corrinoids/porphinoids in the cell, respectively. Polychlorinated methanes would lead to both direct and indirect inhibition, whereas polychlorinated ethylenes would only inhibit methanogenesis indirectly. The model predicts that direct inhibition of methanogenesis is more potent than indirect inhibition.
Ecological and human health risks at an outdoor firing range
Authors: Peddicord Richard K , LaKind Judy S 
Published: March 2010

Abstract
This is the first report in the refereed literature of a quantitative ecological and human health risk assessment at an outdoor recreational shooting range. Contaminants of concern (COC) included lead, other metals, and polycyclic aromatic hydrocarbons (PAH) associated with the clay targets on the shotgun range. Ecological receptors included raptors, deer, foxes, birds, and small mammals. The risk associated with potential incidental ingestion of lead shot by mammals was estimated for the first time. With the exception of lead, risks were minimal to all ecological receptors from all COC acting through all exposure pathways. Lead posed minimal risk to raptors, foxes, or deer. Lead in dietary items posed a small risk to individual birds. The only substantive risk was to individual small mammals and gritingesting birds from the incidental ingestion of lead shot within the shotfall zone at the trap and skeet range. Although effects associated with lead ingestion may occur at the level of individual organisms, ecological impacts are not expected at the population, community, or ecosystem level. This is because density-dependent compensation mechanisms would likely offset any site-related loss of a few individuals that might occur. Human receptors included shooters, range workers, and trespassers. Cancer risks to all receptors from all COC via all exposure pathways were less than 10−4, generally considered an acceptable upper bound excess lifetime cancer risk to an individual. The only noncarcinogenic risk of HQ &gt; 1 was associated with inhalation of copper by those engaged in the voluntary activity of shooting. Two approaches were taken to modeling blood lead in children associated with intermittent exposure. Under the most likely exposure scenario, the mean blood lead level of trespassing children was approx. 2 μg/dL, with less than 1% of children exceeding the 10-μg/dL level of concern. Higher blood lead levels could be possible if children were to trespass in off-limit areas of the shooting range.
Modeling the photolysis of ammonium dinitramide in natural waters
Authors: Beretvas Michelle K , Hassett John P , Burns Susan E , Basford Trisha M 
Published: March 2010

Abstract
Photolytic rate constants for the novel energetic compoundammonium dinitramide(ADNweredetermined in order to understand the fate of ADN in natural bodies of water. Quantum yields were measured between 290 and 400 nm using a lamp system, and these values were combined with absorption of light in a water column to model photolysis rates as a function of depth. The validity of this model was tested in field trials in Onondaga Lake, Syracuse, New York, USA. For a summertime irradiation, half-lives ranged from ∼6 min at the surface to —15 years at a depth of 2 m. The predicted and observed degradation rates of ADN were sufficiently similar to justify use of this simple model. It was also found that the degradation of ADN is not enhanced to any measurable degree by sensitized photoreactions in humic solutions. Thus, the photodegradation of ADN can be predicted throughout the water column of a body of water.
Induction of hepatic cytochrome p450 activities by toxaphene in rat and japanese quail
Authors: Drenth Henk-Jan , Van Oevelen Chris J C , Buitenhuis Christian J K , Berg Martin Van Den 
Published: March 2010

Abstract
Several organochlorine compounds can induce hepatic cytochrome P450 activities. We exposed female Japanese quail and female rats to a single oral dose of technical toxaphene ranging from 0.012 to 40 mg/kg body weight to investigate a possible dose-response relationship for P450 activity induction. The hepatic microsomal alkoxyresorufin dealkylation and steroid hydrox-ylation activities (testosterone, 17β-estradiol) were determined. Only in the highest dose groups (40 mg/kg) of rats and Japanese quail were some P450 activities induced. Pentoxyresorufin-O-dealkylation, formation of 15β-hydroxytestosterone, and formation of 2-hydroxyestradiol were induced significantly (p ≤ 0.05) in rat hepatic microsomes with a factor of 3.9, 3.1, and 2.4, respectively. In Japanese quail hepatic microsomes, the formation rates of 6β-, 15α-, 16β-hydroxytestosterone and androstenedione were induced significantly (p ≤ 0.05) with a factor of 2.4, 6.5, 3.3, and 1.6, respectively. It is concluded that exposure to toxaphene can lead to specific P450 activity induction in rats and Japanese quail but only at doses near reported LD50 values. Because reported toxaphene levels in biota are lower compared with liver residue levels that we have measured in our study, we conclude that it is unlikely that P450 activity induction occurs in wildlife higher in the food chain due to environmental toxaphene exposure.
Contaminant-related disruption of vitamin a dynamics in free-ranging harbor seal (Phoca vitulina) pups from british columbia, canada, and washington state, usa
Authors: Simms Wendy , Jeffries Steven , Ikonomou Michael , Ross Peter S 
Published: March 2010

Abstract
Marine mammals can bioaccumulate high concentrations of lipophilic environmental contaminants, such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-para-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs), through the diet. Both laboratory and wildlife studies have shown that these persistent chemicals can disrupt the regulation of vitamin A (retinol), a dietary hormone required for immune function, reproduction, growth, and development. To determine whether environmental contaminants affect the circulatory vitamin A dynamics of free-ranging harbor seals (Phoca vitulina), we live-captured 61 pups from British Columbia, Canada, and Washington State, USA, and obtained blood and blubber biopsy samples. Harbor seal pups from Washington State were six times more contaminated with total PCBs than pups from British Columbia and had significantly lower circulatory retinol levels. However, when data were corrected for differences in nursing status and analyzed as ungrouped sets of data, circulatory retinol levels were positively correlated with contaminant levels in the blubber of nonnursing pups. This increase in retinol may have resulted from a mobilization of liver vitamin A stores into circulation following exposure to milk-derived contaminants; this has been observed in laboratory animals exposed experimentally. The contaminant-related disruption of vitamin A dynamics observed in our study occurs at a time when vitamin A is required for growth and development.
Morphological and metabolic changes in common carp,Cyprinus carpio, during short-term copper exposure: Interactions between Cu2+ and plasma cortisol elevation
Authors: De Boeck Gudrun , Vlaeminck Andrea , Balm Paul H M , Lock Robert A C , De Wachter Bart , Blust Ronny 
Published: March 2010

AbstractThe effects of increased endogenous cortisol levels were compared with those of sublethal copper exposurein the freshwater common carp, Cyprinus carpio. Fish were exposed to either increased levels of endogenous cortisol (200 ng/ml) or sublethal copper (1.9 μM) alone or were pretreated by elevating plasma cortisol levels prior to copper exposure to assess whether interactions between both treatments occurred. Effects induced by increased cortisol levels included increased Na+/K+-adenosine triphosphate (ATPase) activity and increased plasma Na+ and plasma osmolarity, while copper exposure induced anaerobic metabolism, gill damage, decreasing Na+/K+-ATPase activity, decreasing plasma ion levels, and blood thickening. Pretreatment of copperexposed fish with cortisol partially protected these fish by reducing the copper-induced decrease in Na+/K+-ATPase activity. Overall, the results obtained in this study argue against a major role for cortisol as an intermediate for the toxic effects of copper.