bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bill malformations in double-crested cormorants with low exposure to organochlorines
Authors: Kuiken Thijs , Fox Glen A , Danesik Karen L 
Published: March 2010

Abstract
Eight of 20 newly hatched double-crested cormorants (Phalacrocorax auritus), captured at Doré Lake (Saskatchewan, Canada) and raised in captivity, developed malformed bills when they were 2 to 3 weeks old. Malformation was characterized by abnormal flexure and rotation of the maxilla and mandible, resulting in a crossed bill. By radiography, the premaxillary and dental bones were misshapen. Morphologically similar malformed bills in free-living cormorants have been attributed to exposure to polyhalogenated aromatic hydrocarbons. However, the concentrations of total PCBs in the livers of these captive cormorants with malformed bills and in their diet were lower than have been previously associated with such malformations and were considered too low to have been the cause. The bill malformations may have been caused by deficiency of vitamin D3, because the cormorants were kept indoors without exposure to ultraviolet light and were fed frozen fish that may have been deficient in this vitamin.
Application of whole effluent toxicity test procedures to ambient water quality assessment
Authors: de Vlaming Victor , Connor Valerie , DiGiorgio Carol , Bailey Howard C , Deanovic Linda A , Hinton David E 
Published: March 2010

Abstract
The U.S. Environmental Protection Agency (U.S. EPA) protocols for conducting freshwater toxicity tests have been used in California, USA, to evaluate ambient water quality since 1986. Testing evolved from conducting broad watershed surveys for assessing the distribution of toxicity to conducting detailed studies for identifying chemical causes and sources. Using Cerio-daphnia dubia tests, pulses of diazinon toxicity have been detected over a 10-year period throughout California's Central Valley in waters receiving drainage from dormant orchards. In the 1980s, toxicity to C. dubia, caused by methyl parathion and carbofuran in drainage from rice fields, was detected in the Sacramento River. Rice drainage also was toxic to two important local species, larval striped bass and Neomysis. Throughout the state, diazinon and chlorpyrifos toxicity to C. dubia occurs year-round in waters receiving drainage from urban areas. Several years of monitoring the Alamo River in Imperial County with C. dubia demonstrated a recurring seasonal toxicity pattern. Toxicity during a 3-month autumn period was caused by chlorpyrifos and diazinon and during a 2-month spring period by diazinon and carbofuran. Although most toxicity has been detected with C. dubia and linked to insecticides, other examples of toxicity have been identified. Toxicity to Selenastrum has been linked to copper and zinc from mines and to the herbicide diuron in waters receiving agricultural or urban runoff. Ammonia-caused toxicity, originating from dairies and wastewater treatment plants, to fathead minnows has also been identified. Taken together, the results reveal that the three whole effluent toxicity (WET) testing procedures, in association with toxicity identification evaluations (TIEs) and chemical analyses, can be effective for the identification of an array of toxicants originating from several land use practices. In several cases, alternative land use practices or management strategies have resulted in improved water quality as demonstrated by continued toxicity testing.
Diazinon and chlorpyrifos in urban waterways in Northern California, USA
Authors: Bailey Howard C , Deanovic Linda , Reyes Emilie , Kimball Tom , Larson Karen , Cortright Kristi , Connor Valerie , Hinton David E 
Published: March 2010

Abstract
Samples collected from urban streams in the cities of Sacramento and Stockton, California, USA, during the precipitation season were analyzed for diazinon and chlorpyrifos. Concentrations were determined with enzyme-linked immunosorbent assays specific for each pesticide. Two hundred thirty-one samples from the two cities were analyzed for diazinon; 85% exceeded California Department of Fish and Game water-quality criteria for this pesticide. Chlorpyrifos was measured in 90 of the samples collected from Sacramento and Stockton; 80% exceeded the California Department of Fish and Game criterion for this pesticide. Thirty-six of 47 samples (76.6%) tested for toxicity produced total mortality within 72 h with Ceriodaphnia dubia. Toxicity identification evaluations on selected samples confirmed that toxicity was primarily due to one or both of these pesticides. Uses of diazinon and chlorpyrifos in urban areas include dormant sprays on fruit trees, professional landscape and maintenance uses, and structural pest control. Pesticide concentrations were lower in a catchment favoring commercial and industrial activities compared with a catchment receiving largely residential inputs. Aerial drift from agricultural applications may play a role in storm-water concentrations.
Burrowing owls and agricultural pesticides: Evaluation of residues and risks for three populations in California, USA
Authors: Gervais Jennifer A , Rosenberg Daniel K , Fry D Michael , Trulio Lynne , Sturm Kenneth K 
Published: March 2010

Abstract
We examined selenium, organophosphorus, and organochlorine pesticide residues in egg, footwash, and feather samples from burrowing owls in three populations in central and southern California. Eggs from all sites contained detectable levels of p,p′-dichlorodiphenyldichloroethylene, with the San Joaquin Valley site containing up to 33 μg/g (geometric mean x¯ = 7.52). Only low levels of polychlorinated biphenyls were detected, however (geometric mean x¯ = 1.98, n = 2). Selenuim concentrations were low in all samples (geometric mean x¯ = 0.426, n = 20). Eggshells collected in 1996 were 22% thinner than eggs collected prior to 1937. In addition, feather samples contained low levels of dichlorodiphenyldichloroethylene, and footwash samples indicated exposure to the pesticide chlorpyrifos. Pesticide-use records indicated that one population might also be at risk from applications of aldicarb near nests during the breeding season.
Pollution-induced tolerance to copper of nematode communities in the severely contaminated restronguet creek and adjacent estuaries, Cornwall, United Kingdom
Authors: Millward Rod N , Grant Alastair 
Published: March 2010

AbstractPollution-induced community tolerance (PICT) has been proposed as an indicator of the deleterious effects of pollutants on communities in the field. Nematode assemblages were sampled at 10 estuarine sites that ranged from uncontaminated to grossly contaminated with metals. Relative tolerance of these assemblages to Cu was quantified using acute toxicity tests. There were large differences between sites in tolerance to Cu, and copper tolerance was strongly correlated with severity of contamination. Enhanced Cu tolerance occurred at two sites where Cu concentration in sediment was around 180 μg/g but not at a third site, where Cu concentration was 214 μg/g. This implies a threshold of effects on these nematode communities at ∼200 μg/g Cu. Comparison with studies of nematode community composition in these same estuaries indicates that PICT is at least as sensitive as the best available ecological monitoring methods. It is, however, faster to carry out and requires much less taxonomic expertise. The PICT appears to be a sensitive indicator of ecological effects of pollution and has considerable promise as a monitoring tool.
A case study of integrated risk assessment mapping in the Southland Region of New Zealand
Authors: Hutchinson Gary , McIntosh Peter 
Published: March 2010

Abstract
Risk assessment at the regional level requires quality resource information on critical factors for sustainable land-use decisions. This paper describes a major community initiative underway in the Southland Region of New Zealand involving geographic information systems mapping of 850,000 ha at a 1:50,000 scale. At a southerly latitude of 46° in the southern part of the South Island of New Zealand, the critical factors affecting plant growth are soil quality and air temperature. Air temperature is being measured with a network of 900 automatic data loggers positioned to represent key features of the landscape and recording maximum and minimum temperatures every hour for a full year. Data are then differentially adjusted using the nearest long-term weather station to the site to generate a 30-year normal temperature record and consequent growing-degree-day value for each site. Isocontour maps are then generated to identify microclimates of interest within the landscape. Soils of the area are being mapped at the same time and to the same scale to allow integrated development of the critical information for sustainable land-use decisions. Basic soil attributes will be interpreted to produce maps for crop suitability, vulnerability to structural degradation, and leaching risk. High-class soils will also be identified. An Internet site and a bureau service will be established. This will provide technical support and interpretation of the data for clients to encourage wide use of the information produced by the project. The project is being supported and funded by the local community in the belief that the provision of high-quality resource information will lead to significant employment opportunities in the region.
Methylsulfone polycglorinated biphenyl and 2,2-bis(chlorophenyl)-1,1-dichloroethylene metabolites in beluga whale (Delphinapterus leucas) from the St. Lawrence river estuary and western Hudson bay, Canada
Authors: Letcher Robert J. , Norstrom Ross J , Muir Derek CG , Sandau Courtney D , Koczanski Krystyna , Michaud Robert , De Guise Sylvian , Béland Pierre 
Published: March 2010

Abstract
Kowledge is limited regarding methylsulfone (MeSO2)-polychlorinated biphenyl (PCB), and especially MeSO2–2,2-bis(chlorophenyl)-1,1-dichloroethylene (DDE), metabolites in cetacean species. We hypothesized that the ability of beluga whale (Delphinapterus leucas) to biotransform PCB and DDE compounds, and to form and degrade their MeSO2 PCB and -DDE metabolites, is related to the capacity for xenobiotic metabolism. Adipose biopsies were collected from male and female beluga whale from distinct populations in the St. Lawrence River estuary (STL) and western Hudson Bay (WHB), Canada, which are contrasted by the exposure to different levels of cytochrome P450 enzyme-inducing, chlorinated hydrocarbon contaminants. The PCBs, DDTs, DDEs, 28 MeSO2 metabolites of 14 meta-para chlorine-unsubstituted PCBs, and four MeSO2 metabolites of 4,4′- and 2,4′-DDE were determined. The mean concentrations of total (Σ-) MeSO2-PCB in male STL beluga (230 ng/g), and ratios of Σ-MeSO2-PCB to Σ-PCB (0.05) and Σ-precursor-PCB (0.17) were approximately twofold higher, whereas the Σ-precursor-PCB to Σ-PCB ratio was approximately twofold lower, than in male WHB beluga. Both populations had a low formation capacity for MeSO2-PCBs with ≥six chlorines (&lt;4% of Σ-MeSO2-PCBs). The congener patterns were dominated by trichloro- and tetrachloro-MeSO2-PCBs, and tetrachloro- and pentachloro-MeSO2-PCBs in WHB and STL animals, respectively. In addition to 2- and 3-MeSO2-4,4′-DDE, two unknown MeSO2-2,4′-DDEs were detected. The mean 3-MeSO2-4,4′-DDE concentration in STL beluga (1.2 ng/g) was much greater than in WHB (&lt;0.01 ng/g) animals. The concentrations of 4,4′-DDE, and not 3-MeSO2-4,4′-DDE, increased with age in male STL animals. We demonstrated that sulfone formation and clearance is related to metabolic capacity, and thus PCB, DDE, and MeSO2-PCB and -DDE toxicokinetics differ for STL and WHB beluga. In the past, the capacity of odontocetes for PCB and DDE biotransformation leading to persistent sulfone metabolites has been underestimated. More information is needed for other cetacean species and marine mammals. The results of this study indicate that MeSO2-PCBs and -DDEs need to be included in the toxicologic risk assessment of PCB and DDT exposure in odontocetes, and perhaps for cetaceans in general.
Transformation of 2,4,6-trinitrotoluene in soil in the presence of the earthworm Eisenia andrei
Authors: Renoux Agnès Y. , Sarrazin Manon , Hawari Jalal , Sunahara Geoffrey I 
Published: March 2010

Abstract
The ability of the earthworm Eisenia andrei to metabolize 2,4,6-trinitrotoluene (TNT) was studied in experiments with TNT-spiked soils, dermal contact tests, and with an in vitro assay. Lethality of TNT in a forest sandy soil was first determined (14-d LC50 = 143 mg/kg). Then TNT at lethal and sublethal concentrations was applied to the same soil and was monitored along with its metabolites in extracts of soil and earthworm tissue for up to 14 d postapplication. High performance liquid chromatography-ultra violet analyses indicated that TNT was transformed in the presence of E. andrei by a reductive pathway to 2-amino-4,6-dinitrotoluene (2-ADNT), 4-amino-2,6-dinitrotoluene (4-ADNT), 2,4-diamino-6-nitrotoluene (2,4-DANT), and traces of 2,6-di-amino-4-nitrotoluene (2,6-DANT) in earthworm tissues. This transformation could be explained by either a metabolic mechanism within the earthworm or by the enhancement of an earthworm-associated microbial activity or both. The TNT concentrations decreased from the spiked soils. However, the monoamino-dinitrotoluene (2-ADNT and 4-ADNT) concentrations increased with exposure duration and were dependent on the initial TNT soil concentrations. This was also observed to a lesser extent in the TNT-spiked soils with no earthworms present. The biotransformation of TNT into 2-ADNT, 4-ADNT, and 2,4-DANT and the presence of these metabolites in E. andrei after dermal contact on TNT-spiked filter paper showed that dermal uptake can be a significant exposure route for TNT. In vitro experiments showed that earthworm homogenate could metabolize TNT and form 2-ADNT and 4-ADNT at room temperature and at 37°C. This effect was inhibited by heat inactivation prior to incubation or by incubation at 4°C, suggesting that the biotransformation of TNT in the presence of E. andrei may be enzymatic in nature.
Influence of bioturbation by the amphipod Corophium volutator on fluoranthene uptake in the marine polychaete Nereis virens
Authors: Ciarelli Silvana , Kater Belinda J , van Straalen Nico M 
Published: March 2010

Abstract
The uptake kinetics of fluoranthene in the polychaete worm Nereis virens were investigated in the presence and in the absence of amphipods to examine the effects of sediment bioturbation by the benthic amphipod Corophium volutator on the uptake in worms. Worms only and worms together with two different densities of amphipods were exposed to fluoranthene-spiked sediment for 12 d. Worms and overlying water samples for fluoranthene analyses were taken and total suspended solids in water column were measured after 1, 2, 5, 8, and 12 d. Results showed that in all treatments fluoranthene was rapidly accumulated by N. virens during the first two days and a steady state was reached within five days of exposure. Biota to sediment accumulation factors normalized to lipid concentration and to sediment organic carbon (BAFloc) of worms exposed with the highest number of amphipods were significantly higher (two to three times) compared to worms exposed with fewer or without amphipods after one and two days of exposure. Bioconcentration factors (BCFs), calculated as the ratio between the uptake (k1) and elimination (k2) rate constants were not significantly different among treatments. When BCFs were calculated on the basis of dissolved fluoranthene concentrations (BCFdiss), values of the treatments where worms were exposed with 100 and 300 amphipods were slightly higher than those calculated on the basis of total (dissolved + particle-bound) aqueous fluoranthene (BCFtot). However, the presence of fluoranthene bound to dissolved organic matter could have accounted for lower than expected BCFdiss values. The results suggest that bioturbation by amphipods affected the concentration of fluoranthene in the worms not by changing the worm to water partitioning (k1/k2) but by changing the worm to sediment partitioning (BAFloc). In the treatments with worms a higher mortality of amphipods was found compared to those without worms. The presence of worms might have contributed to lower BCF values than expected.
No-observed-effect concentrations in batch and continuous algal toxicity tests
Authors: Chao Mu-Rong , Chen Chung-Yuan 
Published: March 2010

Abstract
In this study, we compare the no-observed-effect concentrations (NOECs) based on different response parameters, using batch and continuous algal toxicity tests. For both batch and continuous tests, parameters based on total cell volume (TCV) were found to be less sensitive than those related to cell densities. The above observation mainly occurred because, under the stresses from metal toxicants evaluated in this and a previous study, the mean cell volume (MCV) of algae increased considerably. The increase of MCV compensates for the effects brought about by the reduction in cell density and eventually results in less variation in TCVs. This study shows that parameters based on cell density are quite sensitive and ideal for the estimation of NOECs. In addition, comparison of the NOEC values derived from different culture techniques shows that the continuous method generally yields lower NOEC values than that obtained by the batch tests. The results of this study also indicate that the NOEC provides more protection to the test organism than the effective concentration at 10% growth reduction (EC10). For toxicity test methods that produce small variations among replicates, the NOEC is still a good indicator of low toxic effect. Furthermore, for the continuous algal toxicity test, a relatively simple approach is proposed to determine the NOEC values based on the algal culture's control charts. The proposed method produced identical results as those based on conventional hypothesis-testing methods.
Dietary assimilation of a polychlorinated biphenyl in adult sea urchins (Lytechinus pictus) and maternal transfer to their offspring
Authors: Schweitzer Linda E , Bay Steven M , Suffet I H.(Mel) 
Published: March 2010

AbstractThe dietary assimilation of a polychlorinated biphenyl (PCB) in adult sea urchins and the effects of maternal transfer of the PCB on sea urchin offspring were investigated and compared to an earlier study where this PCB produced toxicity to developing sea urchin embryos exposed directly through the water route. Adult sea urchins were allowed to graze on sediment spiked with radiolabeled PCB, 2,2′,4,4′-tetrachlorobiphenyl, for 35 days. The sea urchin L. pictus was found to have a high pollutant extraction efficiency; approx. 62% of the bulk PCB sediment concentration is removed while passing through the gut. Maternal transfer of PCB 2,2′,4,4′-tetrachlorobiphenyl did not prove to be a more sensitive exposure route to developing embryos than the direct water route. Both adult sea urchins and their offspring were found to be resilient to the effects of this PCB at environmentally relevant sediment concentrations and at levels expected on the basis of the critical body residue theory or the model of narcosis. Low toxicity of PCBs to sea urchins at different life stages allows for significant bioaccumulation in sea urchins.
Effects of water quality on development of Xenopus laevis: A frog embryo teratogenesis assay—Xenopus assessment of surface water associated with malformations in native anurans
Authors: Tietge Joseph E , Ankley Gerald T , DeFoe David L , Holcombe Gary W , Jensen Kathleen M 
Published: March 2010

Abstract
The purpose of this work was to determine if surface water from a site in Minnesota, USA, with malformed anurans was able to elicit adverse developmental effects in the frog embryo teratogenesis assay: Xenopus (FETAX) and to isolate and identify the factors responsible for the effects. In the standard FETAX test, 25 organisms are placed in a 10-ml volume of solution that is renewed daily. The organisms are assessed for abnormal development and the test is terminated at 96 h. Under these conditions, the site water adversely affected craniofacial development, gastrointestinal development, and growth. However, these effects were eliminated by each of several different treatments, including diluting the surface-water sample with the standard testing solution, adding dry salts directly to the surface water, testing the organisms in larger volumes of site water, and evaporating site water to increase the concentration of total dissolved solids. These results are consistent with the hypothesis that the low ion concentrations found in this particular site water were responsible for the developmental effects observed in FETAX. This hypothesis was strengthened further when a reconstituted water, made with deionized water and reagent-grade salts to mimic the content of the site water, affected survival, growth, and development similarly to the surface water. In addition, substantial ammonia accumulation in the FETAX tests was documented. These data suggest that the inherent variability in water quality of field-collected samples is important and could result in artifactual developmental effects when using FETAX. As such, the developmental toxicity observed in these FETAX studies is probably not relevant to malformations observed in native anuran species. To obviate this type of problem, the volumes used in the FETAX protocol should be increased for better organism performance and to reduce the possibility of ammonia toxicity.
Pesticide hydroxyl radical rate constants: Measurements and estimates of their importance in aquatic environments
Authors: Armbrust* Kevin L 
Published: March 2010

Abstract
Pesticide degradation by hydroxyl radicals produced in natural water is often cited as an important dissipation mechanism, yet its significance is rarely assessed with other dissipation processes occurring simultaneously in the aquatic environment. The computer model Exposure Analysis Modeling System (EXAMS) is useful for this purpose because it incorporates other dissipation processes and allows the assessment of their dynamics under different environmental conditions. Rate constants of reaction with photochemically generated hydroxyl radicals were measured for the herbicides sulfometuron, bensulfuron methyl, chlorsulfuron, triclopyr, dicamba, molinate, thiobencarb, 2,4-D, mecoprop, and oxadiazon, for the insecticides chlorpyrifos and imidacloprid, and for the fungicide chlorothalonil by competition kinetic methods and were used as the input value for second-order rate oxidation rate constant (KOX) in EXAMS. Hydroxyl radical degradation was estimated to be most significant in shallow water, where sunlight is less attenuated; however, in relatively clear water, it still could contribute to degradation at greater depths for compounds slowly degraded by other mechanisms. For carbaryl at shallow depths, degradation by hydroxyl radicals was predicted to contribute to less than 1% of the degradation profile at pH 8 to as much as 15% of the profile at pH 6. As unique degradation products may be generated by indirect photolysis mechanisms, it should be possible to use EXAMS to estimate when such products may occur for a particular chemical and environmental situation.