bluuebunny/crossref_metadata_2025_split huggingface dataset:
A combined microcosm and field approach to evaluate the aquatic toxicity of azinphosmethyl to stream communities
Authors: Schulz Ralf , Thiere Geraldine , Dabrowski James M. 
Published: March 2010

AbstractWe evaluated the potential effects of the organophosphate insecticide azinphosmethyl (AZ) in a combined microcosm and field approach. The upper regions of the Lourens River, South Africa, are free of contamination (control site), whereas the subsequent stretches flowing through a 400-ha orchard area receive transient insecticide pollution (e.g., 0.82 μ/L AZP, 344 μg/kg chlorpyrifos) following spray drift and runoff (contaminated site). Stones taken from the control site were transferred to outdoor microcosms (1.5 × 0.2 × 0.2 m), providing 12 core species and approximately 350 individuals per microcosm. Microcosms were contaminated for 1 h with AZP (control, 0.2, 1, 5, and 20 μ/L; three replicates each), and acute effects on survival were evaluated 6 d following exposure. The two strongest treatments (measured concentrations: 19.2 ± 1.0 and 4.9 ± 0.3 μ/L, respectively) resulted in a significantly (analysis of variance) reduced invertebrate density, attributed mainly to various insect taxa, such as Demoreptus sp., Castanophlebia sp., Simuliidae, and Chironomidae. In contrast, Aeshna sp., Dugesia sp., Ceratopogonidae, and Cheumatopsyche sp. were unaffected. In parallel, we conducted a quantitative macroinvertebrate survey at the control site and the contaminated site of the Lourens River after the seasonal pesticide application period. The two sites contained a similar number of species but differed considerably in their species composition and abundances. Five of the eight species that were affected by AZP in the microcosm study occurred in the field at significantly lower densities at the contaminated than at the control site or were absent at the contaminated site. All of the four species that were unaffected in the microcosm occurred at significantly higher densities at the contaminated field site. Only 3 of the 12 species reacted differently in the microcosm and the field study. We conclude that microcosm studies employing a field-relevant design could be linked successfully to field studies and our results suggest that transient pesticide contamination affects the aquatic communities of the Lourens River.
Effects of depleted uranium on the health and survival ofCeriodaphnia dubiaandHyalella azteca
Authors: Kuhne Wendy W , Caldwell Colleen A. , Gould William R. , Fresquez Philip R. , Finger Susan 
Published: March 2010

AbstractDepleted uranium (DU) has been used as a substitute for the fissionable enricheduranium component of atomic weapons tested at Los Alamos National Laboratory (LANL) (Los Alamos, NM, USA) since the early 1950s, resulting in considerable concentrations of DU in the soils within the test sites. Although the movement of DU into major aquatic systems has been shown to be minimal, there are many small-order ephemeral streams and areas of standing water in canyons throughout LANL that may be affected by inputs of DU via runoff, erosion, and leaching. Ninety-six-hour acute and 7-d chronic toxicity assays were conducted to measure the toxicity of DU on survival and reproduction of Ceriodaphnia dubia. A 14-d water-only assay was conducted to measure survival and growth of Hyalella azteca. The estimated median lethal concentration (LC50) to produce 50% mortality of the test population for the 96-h Ceriodaphnia dubia assay was 10.50 mg/L. Reproductive effects occurred at a lowest-observable-effect concentration ≥3.91 mg/L with a no-observable-effect concentration of 1.97 mg/L. The estimated 14-d LC50 for the Hyalella azteca assay was 1.52 mg/L. No significant relationship was detected between growth and DU concentrations. Concentrations at which toxicity effects were observed in this study for both invertebrates exceeded concentrations of total uranium observed in runoff from LANL lands. Thus, it is likely that current runoff levels of uranium do not pose a threat to these types of aquatic invertebrates.
Polychlorinated biphenyls and toxaphene in Pacific tree frog tadpoles (Hyla regilla) from the California Sierra Nevada, USA
Authors: Angermann Jeffrey E. , Fellers Gary M. , Matsumura Fumio 
Published: March 2010

AbstractPacific tree frog (Hyla regilla) tadpoles were collected throughout the Sierra Nevada mountain range, California, USA, in 1996 and 1997 and analyzed for the presence of polychlorinated biphenyls (PCBs) and toxaphene. Whole-tadpole Σ PCB levels ranged from 244 ng/g (wet wt) at lower elevations on the western slope to 1.6 ng/g high on the eastern slope, whereas Σ toxaphene levels ranged from 15.6 to 1.5 ng/g. Linear regression of PCB and toxaphene residue levels versus elevation indicated a significant relationship, with an r2 value of 0.33 for PCB and 0.45 for toxaphene indicating a significant elevation effect on PCB and toxaphene bioaccumulation in Sierra Nevada H. regilla. Tadpole samples from sites in east-facing versus west-facing drainage basins showed significant differences in PCB and toxaphene residue levels, suggesting the possibility of a rain-shadow effect in the long-range atmospheric transport of these contaminants to the Sierra Nevada Mountains.
Metabolites of polychlorinated biphenyls in human liver and adipose tissue
Authors: Guvenius Daiva Meironyte , Hassanzadeh Pari , Bergman Ake , Norent Koidu 
Published: March 2010

Abstract
A method for analysis of hydroxylated metabolites of polychlorinated biphenyls (OH-PCBs) was developed and adopted to the previously described method for determination of PCBs and methylsulfonyl-PCBs (MeSO2-PCBs) in human liver and adipose tissue. The concentrations of OH-PCBs (14 congeners), MeSO2-PCBs (24 congeners), and PCBs (17 congeners) in five paired samples of human liver and adipose tissue are reported. The sum of OH-PCB congeners was higher in liver (7–175 ng/g lipids) than in adipose tissue (0.3–9 ng/g lipids). In both liver and adipose tissue, 2,2′,3,4,4′,5′-hexachloro-3′-biphenylol (3′-OH-CB138) and 2,2′,3,3′,4,5′-hexachloro-4′-biphenylol (4′-OH-CB130) were the predominant hydroxylated PCB metabolites. The sum of OH-PCB congeners were of the same order of magnitude as those of methylsulfonyl metabolites of PCB in the same samples, 12 to 358 ng/g lipids and 2 to 9 ng/g lipids in liver and adipose tissue, respectively. The levels of PCBs were similar in liver and adipose tissue, 459 to 2,085 ng/g lipids and 561 to 2,343 ng/g lipids, respectively. The sum of OH-PCBs and the sum of MeSO2-PCBs correlated to the sum of PCBs. The determined PCB metabolites constituted 3 to 26% of total PCB concentration in the liver and 0.3 to 0.8% of total PCBs in the adipose tissue samples.
Relationships between contaminant levels in marine sediments and their biological effects on embryos of oysters,Crassostrea gigas
Authors: Geffard Olivier , Budzinski Helene , His Edouard , Seaman Matthias N. L. , Garrigues Philippe 
Published: March 2010

AbstractSurface sediment samples from 10 coastal locations were analyzed with respect to their physical and chemical characteristics as well as their biological quality. The toxicity of the decanted fresh and freeze-dried sediments and of their elutriates was assessed by bioassays with embryos of the oysters Crassostrea gigas. The concentration inhibiting normal embryogenesis in 20% of the larvae (EC20) was used as a measure of toxicity and compared with the physical and chemical properties of the sediments and elutriates by principal components analysis. Decanted whole sediments were one to four orders of magnitude more toxic than their elutriates because the latter have lower contaminant concentrations. The biological effects of decanted whole sediment depended mostly on the levels of heavy metals and polycyclic aromatic hydrocarbons (PAHs), while in the case of the elutriates, the toxicity was mainly correlated with the concentrations of total ammonia and of dissolved organic carbon (DOC). Freeze-dried sediments and their elutriates were up to one order of magnitude more toxic than fresh sediments and elutriates, respectively, presumably because the freeze-drying procedure increases pollutant bioavailability or causes a release of unidentified organic compounds having toxic effects.
Timing of exposure to a pulp and paper effluent influences the manifestation of reproductive effects in rainbow trout
Authors: Van den Heuvel Michael R. , Ellis Rosanne J. 
Published: March 2010

AbstractRainbow trout were exposed to a secondary treated, thermomechanical/bleached kraft pulp and paper effluent in 12,000-L, flow-through exposure tanks at an environmental research facility located at a pulp and paper mill in Kawerau, New Zealand. Trout (age, 2+ years) were obtained from a local hatchery and exposed either to upstream river water or a nominal concentration of 12% (v/v) effluent diluted in upstream river water. Three treatment groups were used: Effluent exposure that started approximately three months before gonadal growth (eight-month total exposure), effluent exposure that started approximately halfway through gonadal development (two-month total exposure), and trout exposed to reference water alone for the total duration of the experiment. Trout were sacrificed just before spawning; exposure, growth, and reproductive endpoints were assessed during and at the termination of the experiment. Reduction in growth was observed in both sexes in the eight-month treatment group relative to the river water reference treatment group. No differences were observed in condition factor or liver size in either treatment. Females in the eightmonth exposure group also had significantly lower ovary weight. The two-month exposure group showed no differences from the reference group in growth or somatic indices. Estradiol and testosterone were reduced in blood samples taken from the eight-month exposure group by four months into the experiment as compared to the reference treatment. Steroid and vitellogenin levels in individual female trout from this treatment were significantly correlated with gonadosomatic indices (GSI) measured at the termination of the experiment. The GSI was not correlated strongly or consistently with pregnenolone, nor were any treatment-related pregnenolone differences observed, indicating that the steroid hormone reductions likely were not related to cholesterol side-chain cleavage. Male trout showed significant induction of vitellogenin and lower 11-ketotestosterone during the experiment (only the eight-month group was examined), but this did not result in any significant differences in testes development. Thus, this study has shown an impact of pulp mill effluent exposure on the reproductive physiology of female trout that appeared to be hormonally mediated. Furthermore, the effect could only be manifest when the exposure was initiated before the start of gonad development.
Influence of trophic position on organochlorine concentrations and compositional patterns in a marine food web
Authors: Ruus Anders , Ugland Karl Inne , Skaare Janneche Utne 
Published: March 2010

AbstractThe accumulation of polychlorinated biphenyls (PCBs), DDTs (p,p′-DDT [1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane], o,p′-DDT [1,1,1-trichloro-2-(2-chlorophenyl)-2-(4-chlorophenyl)ethane], p,p′-DDD [1,1-dichloro-2,2-bis(4-chlorophenyl)ethane], o,p′-DDD [1,1-dichloro-2-(2-chlorophenyl)-2-(4-chlorophenyl)ethane], and p,p′-DDE [1,1-dichloro-2,2-bis(4-chlorophenyl)ethene]), chlordanes (trans-chlordane, cis-chlordane, trans-nonachlor, cis-nonachlor and oxychlordane), hexachlorocyclohexanes (α-, β-, and γ-isomers), hexachlorobenzene, and mirex was investigated in a marine food web from southeastern Norway. The food web consisted of the polychaete Nereis diversicolor, lesser sandeel (Ammodytes tobianus), three species of gobys (Gobiusculus flavescens, Pomatoschistus sp., and Gobius niger), bullrout (Myoxocephalus scorpius), cod (Gadus morhua), herring gull (Larus argentatus), and harbor seal (Phoca vitulina). The results show that interspecies differences in organochlorine (OC) compositional patterns in the food web depend on several factors (allometric, biochemical, physical, and physicochemical) specific to both the chemicals and the organisms. The importance of dietary accumulation and metabolic capacity increases toward higher trophic levels, while the OC patterns are to a larger extent determined by the lipophilicity and water solubility of the compounds at lower trophic levels. Furthermore, stable nitrogen isotopes provided a continuous measure of trophic position, rendering us capable of quantifying the increases in the concentrations of ΣPCB, Σdichorodiphenyltrichloroethane (DDT), and Σchlordane (CHL) and the percentages of highly chlorinated PCBs through the food web. The information provided may be important for future modeling of the fate of organochlorine contaminants in marine food webs.
Evaluation of reduced sediment volume toxicity test procedures using the marine amphipod Ampelisca abdita
Authors: Ferretti James A. , Calesso Diane F. , Lazorchak James M. , Durham Curtis O. 
Published: March 2010

Abstract
During the past 20 years, the role of sediment toxicity tests has expanded from testing of primarily dredged material to risk assessment, decontamination technologies, large-scale regional sediment-quality assessments, and toxicity identification evaluations. Sediment toxicity tests are needed that can provide reliable data using less sediment and smaller test chambers, thus utilizing resources more efficiently. We compared survival results from 10-d standard marine amphipod tests at 20°C using 200 ml of sediment to reduced-volume tests containing 20 or 50 ml of sediment and found no significant differences. Similar survival also was observed in tests conducted for 7-d at 23°C versus the standard 10-d exposure at 20°C. However, amphipod sensitivity was significantly less in reduced-volume tests conducted for only 4- or 7-d at 20°C. The 10-d sediment toxicity tests using 50 ml of sediment provided comparable results to the standard protocol, whereas time for sampling, preparing, and sieving sediments for a test was substantially reduced.
17α-ethynylestradiol-induced vitellogenin gene transcription quantified in livers of adult males, larvae, and gills of fathead minnows (Pimephales promelas)
Authors: Lattier David L. , Reddy Tirumuru V. , Gordon Denise A. , Lazorchak James M. , Smith Mark E. , Williams Daniel E. , Wiechman Barry , Flick Robert W. , Miracle Ann L. , Toth Gregory P. 
Published: March 2010

Abstract
We have applied a method for quantifying relative levels of messenger RNA (mRNA) transcription to assess chemically induced gene expression in fathead minnows (Pimephales promelas). Synthetic oligonucleotides designed for the fathead minnow vitellogenin gene transcription product were used in a reverse transcription polymerase chain reaction (RT-PCR) protocol. This sensitive and rapid strategy detected vitellogenin gene transcription in livers of male fathead minnows exposed to concentrations as low as 2 ng/L of the endocrine-disrupting compound 17-α-ethynylestradiol for 24 h. Surprisingly, vitellogenin transcription products also were detected in gill tissue and in 48-h-old posthatch fathead minnow larvae. Relative levels of vitellogenin gene induction among individuals were quantified in a single-step reaction (PCR multiplex) with 18S rRNA universal primers and Competimerst concurrently with fathead minnow vitellogenin oligonucleotides. This quantitative approach will markedly enhance detection of the first cellular event of estrogenic exposure to aquatic ecosystems in both field and laboratory systems. Use of the model provides sensitivity of detection at a concentration below those that cause mortality or visible signs of stress in fish or other aquatic organisms. The model may also provide an in vivo screening method for estrogenlike endocrine-disrupting compounds.
Embryotoxic potential of persistent organic pollutants extracted from tissues of guillemots (Uria aalge) from the Baltic Sea and the Atlantic Ocean
Authors: De Roode Daphne F. , Gustavsson M. Bodil , Rantalainen Anna-lea , Klomp Anette V. , Koeman Jan H. , Bosveld Albertus T. C. 
Published: March 2010

AbstractThe Baltic Sea is a heavily polluted area. To assess the current contaminant pressure on the common guillemot (Uria aalge) living there, whole-body extracts of guillemots from the Baltic Sea were prepared and subdivided over six fractions, which differed in composition due to lipophilicity and polarity of the contaminants. The fractions were tested in the chicken embryo assay and compared to fractions of Atlantic guillemot extracts. Fertilized chicken eggs were injected with 0.03, 0.3, or 3 bird egg equivalents (BEQ) of the contaminants present in the fractions and then incubated for 19 d. Endpoints were selected to cover several mechanisms that may play a role in reproductive failures of fish-eating birds. Fractions I and IV from the Baltic guillemots induced ethoxyresorufin-O-deethylase (EROD) activity up to 15-fold in embryos exposed to 0.3 BEQ and up to 17-fold in embryos exposed to 3 BEQ. Corresponding Atlantic fractions induced EROD activity only at the higher dose of 3 BEQ. Morphological alterations were observed in the bursa of Fabricius in embryos exposed to the fractions that induced EROD, and for the Baltic fractions, this was apparent at the dose of 0.3 BEQ. The higher toxic potency of fractions I and IV was confirmed by higher mortality and occurrence of malformations among embryos exposed to these fractions. No other effects were observed; morphometry, hepatic porphyrin levels, thiamine-dependent enzymes, and acetylcholinesterase activity were not affected by any fraction. During interpretation of the results, concentrations in the whole-body guillemot extracts were compared to concentrations reported in field studies. In general, concentrations in the guillemot extract were lower than those associated with biomarker responses in other wildbird species. However, because the relative sensitivity of guillemot toward immunotoxic effects remains to be resolved, effects on the immunocompetence of guillemot could not be excluded.
In vitro assessment of potential mechanism-specific effects of polybrominated diphenyl ethers
Authors: Villeneuve Daniel L. , Kannan Kurunthachalam , Priest Benjamin T. , Giesy John P. 
Published: March 2010

Abstract
This study examined the ability of environmentally relevant concentrations of 10 different polybrominated diphenyl ethers (PBDEs) to induce aryl hydrocarbon receptor (AhR)-and estrogen receptor (ER)-mediated gene expression in vitro. It also examined the ability of PBDEs to displace steroid hormones from serum proteins in vitro. At concentrations ranging up to 880 ng/ml, none of the PBDEs significantly displaced tritiated 17β-estradiol (E2) or testosterone from hormone-stripped carp serum. At concentrations ranging up to 500 ng/ml, 9 of 10 PBDEs tested failed to induce ER- or AhR-mediated gene expression in MVLN and H4IIE-luc cells, respectively. One congener, 3,3′,4,4′,5-pentabromodiphenylether (BDE 126), induced significant AhR-mediated gene expression at 500 ng/ml, but the magnitude of induction was only 13% of that caused by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Overall, the PBDEs tested were found to be at least 200,000 times less potent than TCDD and 50,000 times less potent than E2 for inducing AhR- and ER-mediated gene expression, respectively.
Freshwater to saltwater toxicity extrapolation using species sensitivity distributions
Authors: Wheeler James R. , Leung Kenneth M. Y. , Morritt David , Sorokin Neal , Rogers Howard , Toy Robin , Holt Martin , Whitehouse Paul , Crane Mark 
Published: March 2010

Abstract
There is generally a lack of saltwater ecotoxicity data for risk assessment purposes, leaving an unknown margin of uncertainty in saltwater assessments that utilize surrogate freshwater data. Consequently, a need for sound scientific advice on the suitability of using freshwater data to extrapolate to saltwater effects exists. Here we use species sensitivity distributions to determine if freshwater datasets are adequately protective of saltwater species assemblages for 21 chemical substances. For ammonia and the metal compounds among these data, freshwater data were generally protective because freshwater organisms tended to be more sensitive. In contrast, for pesticide and narcotic compounds, saltwater species tended to be more sensitive and a suitable uncertainty factor would need to be applied to surrogate freshwater data. Biological and physicochemical factors contribute to such differences in freshwater and saltwater species sensitivities, but the species compositions of datasets used are also important.
A modeling approach to link food availability, growth, emergence, and reproduction for the midge Chironomus riparius
Authors: Péry Alexandre R. R. , Mons Raphaël , Flammarion Patrick , Lagadic Laurent , Garric Jeanne 
Published: March 2010

Abstract
We present models to link feeding with growth, emergence, and reproduction of the midge Chironomus riparius. These models are based on assumptions about the biology of this species and distinguish between males and females. The assumptions are the isomorphism of the chironomidae, the fact that much more energy is used for growth than for maintenance, and the existence of a maximum length for male and female larvae that does not depend on food availability. We supported our assumptions by experimental data and estimated the parameters of the model. We then successfully predicted the length pattern of 2-d-old larvae exposed in an artificial sediment to different feeding levels with different starting densities and also linked emergence time and growth pattern. We found our model to be consistent with data from another study and another species (Chironomus plumosus). As for reproduction, the mean number of eggs per mass was described as a linear function of feeding quantity. Our models could be used in sediment risk assessment to choose feeding level, to build effects models, or to predict the effects of toxicants at the population level.
The potential for estradiol and ethinylestradiol to sorb to suspended and bed sediments in some English rivers
Authors: Holthaus Karlijn I. E. , Johnson Andrew C. , Jürgens Monika D. , Williams Richard J. , Smith Jennifer J. L. , Carter Joy E. 
Published: March 2010

Abstract
The endocrine-disrupting impact of steroid estrogens on fish will be strongly influenced by their distribution between sediment and water. Laboratory studies were performed to investigate the potential for sorption of 17β-estradiol (E2) and 17α-ethinylestradiol (EE2) to bed and suspended sediments taken from five British rivers. Sediment material was collected from the Rivers Aire and Calder (located in urban and industrialized areas in Yorkshire, UK), the River Thames (at a relatively rural site in Oxfordshire, UK), and from the estuaries of the Rivers Tees and Tyne. Using anaerobic conditions to inhibit biodegradation, it was found that 80 to 90% of binding to bed sediments was complete within 1 d, but that an equilibrium had not been reached after 2 d. Bed sediments gave distribution coefficients (Kd) ranging from 4 to 74 L/kg for E2 and from 8 to 121 L/kg for EE2 for samples taken over a range of seasons and locations. Sorption to suspended sediment gave Kd values ranging from 21 to 122 L/kg for E2 and 19 to 260 L/kg for EE2. However, these Kd values suggest less than 1% removal of the steroid estrogens from the aqueous phase given the ambient suspended sediment concentration. In the bed sediments, higher Kd values were associated with smaller particle size and higher organic carbon content. In most cases, the Kd values obtained for EE2 were higher than those for E2 by a factor of up to three.