Extracellular and intracellular uptake of zinc in a photosynthetic biofilm matrix:
No abstract available.
Bulletin of Environmental Contamination and Toxico↗
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Influence of fluctuating water levels on mercury concentrations in adult walleye
[No abstract available]
Bulletin of Environmental Contamination and Toxico↗
A multi-residue method for the analysis of pesticides and pesticide degradates in water using HLB solid-phase extraction and gas chromatography-ion trap mass spectrometry
A method was developed for the analysis of over 60 pesticides and degradates in water by HLB solid-phase extraction and gas-chromatography/mass spectrometry. Method recoveries and detection limits were determined using two surface waters with different dissolved organic carbon (DOC) concentrations. In the lower DOC water, recoveries and detection limits were 80%–108% and 1–12 ng/L, respectively. In the higher DOC water, the detection limits were slightly higher (1–15 ng/L). Additionally, surface water samples from four sites were analyzed and 14 pesticides were detected with concentrations ranging from 4 to 1,200 ng/L.
Bulletin of Environmental Contamination and Toxico↗
Contaminant levels in rainbow trout, Oncorhynchus mykiss, and their diets from Missouri coldwater hatcheries
Organochlorine and metal contaminants often occur in commercial fish diets and can accumulate in fish to levels of concern for human consumption. Contaminant levels were investigated in diet and rainbow trout fillets from Missouri coldwater hatcheries used in 'put and take' fisheries. The average fillet:diet ratio was <0.1 for lead and cadmium, 0.4-0.6 for organochlorine compounds, and about 0.8 for mercury. Trout fillet concentrations for all contaminants were low (<50 ng/g) and below Missouri's fish consumption advisory trigger levels. ?? 2008 Springer Science+Business Media, LLC.
Bulletin of Environmental Contamination and Toxico↗
Element patterns in feathers of nestling Black-Crowned Night-Herons, Nycticorax nycticorax L., from four colonies in Delaware, Maryland, and Minnesota
The pattern of elements in nestling black-crowned night-heron feathers from a rural Minnesota colony differed from colonies in industrialized regions of Maryland and Delaware. Except for chromium, however, the differences did not reflect the elements associated with waters and sediments of the Maryland and Delaware colonies. Therefore, elements in water and sediment do not necessarily bioaccumulate in night-heron feathers in relation to potential exposure. Although trace element patterns in feathers indicated differences among geographical locations, they did not separate all locations well and their usefulness as an indicator of natal colony location may be limited.
Bulletin of Environmental Contamination and Toxico↗
Trophic transfer efficiency of mercury to lake whitefish Coregonus clupeaformis from its prey
In the laboratory, net trophic transfer efficiency of mercury to lake whitefish Coregonus clupeaformis from its prey was estimated to be 63.5%. Assuming that gross trophic transfer efficiency of mercury to lake whitefish from its prey was equal to 80%, we estimated that the rate at which lake whitefish eliminated mercury was 0.000730 day-1. Our laboratory estimate of mercury elimination rate was 2.4 times lower than the value predicted by a published regression equation developed from previous studies on mercury elimination rates for fish. Thus, our results suggested that mercury elimination rates for fish have been overestimated in previous studies. ?? 2008 Springer Science+Business Media, LLC.
Bulletin of Environmental Contamination and Toxico↗
Waste-indicator and pharmaceutical compounds in landfill-leachate-affected ground water near Elkhart, Indiana, 2000-2002
Four wells downgradient from a landfill near Elkhart, Indiana were sampled during 2000–2002 to evaluate the presence of waste-indicator and pharmaceutical compounds in landfill-leachate-affected ground water. Compounds detected in leachate-affected ground water included detergent metabolites ( p -nonylphenol, nonylphenol monoethoxylate, nonylphenol diethoxylate, and octylphenol monoethoxylate), plasticizers (ethanol-2-butoxy-phosphate and diethylphthalate), a plastic monomer (bisphenol A), disinfectants (1,4-dichlorobenzene and triclosan), an antioxidant (5-methyl-1H-benzotriazole), three fire-retardant compounds (tributylphosphate and tri(2-chloroethyl)phosphate, and tri(dichlorisopropyl)phosphate), and several pharmaceuticals and metabolites (acetaminophen, caffeine, cotinine, 1,7-dimethylxanthine, fluoxetine, and ibuprofen). Acetaminophen, caffeine, and cotinine detections confirm prior indications of pharmaceutical and nicotinate disposal in the landfill.
Indiana↗
Chronic toxicity of diphenhydramine hydrochloride and erythromycin thiocyanate to Daphnia, Daphnia magna, in a continuous exposure test system
Diphenhydramine hydrochloride (DH; Benadryl™, an over-the-counter antihistamine) and erythromycin thiocyanate (ET; a commonly used macrolide antibiotic) are pharmaceutical compounds whose chronic toxicity to Daphnia magna had not been characterized. Continuous exposure to DH concentrations about 5 times greater than the maximum reported environmental concentration of 0.023 μg/L for 21 days or to ET concentrations about 40 times the maximum reported environmental concentration of 6 μg/L for 21 days did not significantly impact D . magna survival and production. In this study the no observable effect concentration for DH was 0.12 μg/L and for ET was 248 μg/L.
Bulletin of Environmental Contamination and Toxico↗
Influence of Physiochemical and watershed characteristics on mercury concentration in walleye, Sander vitreus , M.
Elevated mercury concentration has been documented in a variety of fish and is a growing concern for human consumption. Here, we explore the influence of physiochemical and watershed attributes on mercury concentration in walleye ( Sander vitreus, M . ) from natural, glacial lakes in South Dakota. Regression analysis showed that water quality attributes were poor predictors of walleye mercury concentration (R 2 = 0.57, p = 0.13). In contrast, models based on watershed features (e.g., lake level changes, watershed slope, agricultural land, wetlands) and local habitat features (i.e., substrate composition, maximum lake depth) explained 81% ( p = 0.001) and 80% ( p = 0.002) of the variation in walleye mercury concentration. Using an information theoretic approach we evaluated hypotheses related to water quality, physical habitat and watershed features. The best model explaining variation in walleye mercury concentration included local habitat features (W i = 0.991). These results show that physical habitat and watershed features were better predictors of walleye mercury concentration than water chemistry in glacial lakes of the Northern Great Plains.
Bulletin of Environmental Contamination and Toxico↗
Chronic toxicity of erythromycin thiocyanate to Daphnia magna in a flow-through, continuous exposure test system
Approval of a new animal drug application for AQUAMYCIN 100 ® (erythromycin thiocyanate; ET) to treat freshwater salmonid species with bacterial kidney disease is being pursued in the US. As part of the approval process, ET’s impact on an aquatic environment had to be described in an environmental assessment. The environmental assessment was lacking data to characterize the effect ET would have on a chronically exposed aquatic invertebrate organism. A major step to fulfilling the environmental assessment was completed after conducting a comprehensive study continuously exposing Daphnia magna to ET for 21 days. Results indicated that the no observable effect concentration for ET was 179 μg/L.
Bulletin of Environmental Contamination and Toxico↗
Toxicity of chloride under winter low-flow conditions in an urban watershed in central Missouri, USA
Deicers such as sodium chloride and calcium chloride are used to treat snow and ice on road surfaces and have been identified as potential stressors on aquatic life. Hinkson Creek is an urban stream on the Missouri 303(d) list of impaired waters and is classified as impaired due to urban non-point source pollution. A 7-day toxicity test using Ceriodaphnia dubia was conducted to assess the toxicity of stream water during snowmelt at seven sites within the Hinkson Creek watershed. Chloride concentrations at two sites (Site 6, 1252 mg Cl/L; Site 4, 301 mg Cl/L) exceeded the U.S. Environmental Protection Agency chronic criterion (230 mg Cl/L). Survival (30 %) and total reproduction (6.9 young/adult) of C. dubia at Site 6 was significantly lower than survival (100 %) and total reproduction (30.4 young/adult) at Site 1 (reference site). Results indicate that chloride concentrations are elevated above water-quality criteria and that chloride may be a significant chemical stressor for macroinvertebrate communities during winter low-flow conditions in the Hinkson Creek watershed.
Missouri↗
Implementation of a non-lethal biopsy punch monitoring program for mercury in smallmouth bass, Micropterus dolomieu Lacepede, from the Eleven Point River, Missouri
A non-lethal biopsy method for monitoring mercury (Hg) concentrations in smallmouth bass ( Micropterus dolomieu ; smallmouth) from the Eleven Point River in southern Missouri USA was evaluated. A biopsy punch was used to remove a muscle tissue plug from the area immediately below the anterior dorsal fin of 31 smallmouth. An additional 35 smallmouth (controls) were held identically except that no tissue plug was removed. After sampling, all fish were held in a concrete hatchery raceway for 6 weeks. Mean survival at the end of the holding period was 97 % for both groups. Smallmouth length, weight and Fulton’s condition factor at the end of the holding period were also similar between plugged and non-plugged controls, indicating that the biopsy procedure had minimal impact on growth under these conditions. Tissue plug Hg concentrations were similar to smallmouth Hg data obtained in previous years by removing the entire fillet for analysis.
Missouri↗
Effects of smallmouth buffalo, Ictiobus bubalus biomass on water transparency, nutrients, and productivity in shallow experimental ponds
The smallmouth buffalo Ictiobus bubalus is a native benthivore to floodplain lakes in the Yazoo River Basin, USA. Based on evidence from other benthivorous fish studies we hypothesized high biomasses of I. bubalus contribute to poor water quality conditions. We tested this hypothesis in shallow (< 1.5 m) 0.05 ha earthen ponds at three stocking biomasses over a 10-week period during the summer of 2012. The most notable results from the permutational multivariate analysis of variance suggest I. bubalus at high and moderate biomasses significantly (p < 0.05) enhanced turbidity and suspended solid levels while decreasing Secchi depth. Our results suggest that effects of I. bubalus on water clarity may have considerable ecological implications in natural habitats such as shallow floodplain lakes.
Bulletin of Environmental Contamination and Toxico↗
Mercury elimination rates for adult northern pike Esox lucius : evidence for a sex effect
We examined the effect of sex on mercury elimination in fish by monitoring isotope-enriched mercury concentrations in the muscle tissue of three adult female and three adult male northern pike Esox lucius, which had accumulated the isotope-enriched mercury via a whole-lake manipulation and were subsequently moved to a clean lake. Mercury elimination rates for female and male northern pike were estimated to be 0.00034 and 0.00073 day −1 , respectively. Thus, males were capable of eliminating mercury at more than double the rate than that of females. To the best of our knowledge, our study represents the first documentation of mercury elimination rates varying between the sexes of fish. This sex difference in elimination rates should be taken into account when comparing mercury accumulation between the sexes of fish from the same population. Further, our findings should eventually lead to an improved understanding of mechanisms responsible for mercury elimination in vertebrates.
Bulletin of Environmental Contamination and Toxico↗
A simple control for sediment-toxicity exposures using the amphipod, Hyalella azteca
Sediment-toxicity exposures comparing survival and growth of the freshwater amphipod, Hyalella azteca, are often components of aquatic-habitat assessments. Standardized exposure methods have been established and require evaluations for quality assurance. Test acceptability using performance-based criteria can be determined from exposures to control sediments, which are collected from the environment or formulated from commercially available components. Amending sand with leached alfalfa solids provided a simple formulated sediment that elicited consistently acceptable survival and growth in 28-day exposures with and without a daily feeding regime. A procedure is described for preparing the sediment along with results from comparisons among sand, amended sand, and field-collected sediments that incorporated three feeding regimes.
Bulletin of Environmental Contamination and Toxico↗
Baseline blood Pb levels of black-necked stilts on the upper Texas coast
There are no known biological requirements for lead (Pb), and elevated Pb levels in birds can cause a variety of sub-lethal effects and mortality. Historic and current levels of Pb in mottled ducks ( Anas fulvigula ) suggest that environmental sources of Pb remain available on the upper Texas coast. Because of potential risks of Pb exposure among coexisting marsh birds, black-necked stilt ( Himantopus mexicanus ) blood Pb concentrations were measured during the breeding season. Almost 80 % (n = 120) of 152 sampled stilts exceeded the background threshold (>20 μg/dL) for Pb exposure. However, blood Pb concentrations did not vary by age or gender, and toxic or potentially lethal concentrations were rare (<5 %). Consistent, low-level blood Pb concentrations of black-necked stilts in this study suggest the presence of readily bioavailable sources of Pb, although potential impacts on local stilt populations remain unclear.
Bulletin of Environmental Contamination and Toxico↗
A pilot study testing a natural and a synthetic Molluscicide for controlling invasive apple snails ( Pomacea maculata )
Pomacea maculata (formerly P. insularum ), an apple snail native to South America, was discovered in Louisiana in 2008. These snails strip vegetation, reproduce at tremendous rates, and have reduced rice production and caused ecosystem changes in Asia. In this pilot study snails were exposed to two molluscicides, a tea ( Camellia sinensis ) seed derivative (TSD) or niclosamide monohydrate (Pestanal ® , 2′,5-dichloro-4′-nitrosalicylanilide, CAS #73360-56-2). Mortality was recorded after exposure to high or low concentrations (0.03 and 0.015 g/L for TSD, 1.3 and 0.13 mg/L for niclosamide). The TSD induced 100 % mortality at both concentrations. Niclosamide caused 100 % and 17 % mortality at high and low concentrations respectively. These molluscicides were also tested on potential biocontrol agents, the red swamp crayfish ( Procambarus clarkii ) and redear sunfish ( Lepomis microlophus ). No crayfish mortalities occurred at either concentration for either chemical, but sunfish experienced 100 % mortality with TSD (0.03 g/L), and 21 % mortality with niclosamide (0.13 mg/L).
Bulletin of Environmental Contamination and Toxico↗
Retrospective: Adjusting contaminant concentrations in bird eggs to account for moisture and lipid Loss during their incubation
By the 1960s, research and monitoring efforts on chlorinated pesticide residues in tissues of wildlife were well underway in North America and Europe. Conservationists and natural resource managers were attempting to resolve whether pesticide exposure and accumulated residues were related to population declines in several species of predatory and scavenging birds (e.g., bald eagle Haliaeetus leucocephalus , peregrine falcon Falco peregrinus , brown pelican Pelecanus occidentalis and osprey Pandion haliaetus ). The avian egg was a favored sampling matrix even before the realization that eggshell thinning was linked to population declines (Ratcliffe 1967 ; Hickey and Anderson 1968 ) and that the concentration of p,p ’-DDE in an egg was associated with the shell thinning phenomenon (e.g., Blus et al. 1972 ; Wiemeyer et al. 1988 ). The necessity for making wet-weight concentration adjustments to account for natural moisture loss during incubation of viable eggs was realized. Correction for the more dramatic moisture loss in non-viable decaying eggs was recognized as being paramount. For example, the ∑DDT residues in osprey eggs were reported to vary by as much as eightfold without accounting for moisture loss adjustments (Stickel et al. 1965 ). In the absence of adjusting concentrations to the fresh wet-weight that was present at the time of egg laying, the uncorrected values exaggerated contaminant concentrations, yielding artifactual results and ultimately incorrect conclusions. The adjustment to fresh wet-weight concentration is equally important for many other persistent contaminants including PCBs, dioxins, furans, and brominated diphenyl ethers.
Bulletin of Environmental Contamination and Toxico↗