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John P Giesy - One of the best experts on this subject based on the ideXlab platform.
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productivity of tree swallows tachycineta bicolor exposed to pcbs at the kalamazoo river Superfund Site
Journal of Toxicology and Environmental Health, 2006Co-Authors: Arianne M Neigh, Monica A Maccarroll, Matthew J Zwiernik, Alan L Blankenship, Paul D. Jones, John L. Newsted, John P GiesyAbstract:A 123-km stretch of the Kalamazoo River in Michigan, was designated a Superfund Site in 1990 due to historical releases of effluent containing polychlorinated biphenyl (PCB)-contaminated paper waste. Risk to bird species in the river ecosystem was evaluated using the tree swallow (Tachycineta bicolor) as a monitor for possible effects due to PCB exposure at two nesting locations, one in the Superfund Site and one in an upstream reference location that is less contaminated with PCBs. In 2 of the 3 years of the study, clutch size at the contaminated location was 3.7 ± 1.4 and 4.8 ± 0.73 eggs per nest (mean ± SD), which was significantly less than the clutch size at the reference location (5.0 ± 1.1 and 5.3 ± 1.1 eggs per nest). However, there were no statistically significant differences in fledging success, predicted brood size, predicted number of fledglings, or growth of nestlings between the Kalamazoo River Superfund Site and an upstream reference location with lesser concentrations of PCBs in the sedim...
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tree swallow tachycineta bicolor exposure to polychlorinated biphenyls at the kalamazoo river Superfund Site michigan usa
Environmental Toxicology and Chemistry, 2006Co-Authors: Arianne M Neigh, Matthew J Zwiernik, Patrick W Bradley, Cyrus S Park, Alan L Blankenship, Paul D. Jones, John L. Newsted, John P GiesyAbstract:In 1990, a portion of the Kalamazoo River in Michigan, USA, was designated a Superfund Site because of the presence of polychlorinated biphenyls (PCBs) in the sediment and floodplain soils. During a four-year period from 2000 to 2003, several avian species were monitored for reproductive effects and concentrations of PCBs in tissues attributed to food chain transfer from contaminated sediments. The tree swallow (Tachycineta bicolor) was chosen as a model receptor for contamination of passerine species. A top-down methodology was used to evaluate the bioaccumulation of PCBs, including non-ortho and mono-ortho congeners, in tree swallow eggs, nestlings, and adults at the Kalamazoo River area of concern (KRAOC) and at an upstream reference Site. Generally, a sixfold difference in tissue concentrations of total PCBs was observed between the two Sites with concentrations in eggs and nestlings at the KRAOC ranging from 0.95 to 15 mg PCB/g wet weight. Concentrations of 2,3,7,8- tetrachlorodibenzo-p-dioxin equivalents (TEQsWHO2Avian) for PCBs, based on bird-specific World Health Organization toxic equiv- alence factors, were 10- to 30-fold greater in the KRAOC than at the reference location. Egg and nestling TEQsWHO2Avian ranged from 0.21 to 2.4 ng TEQ/g wet weight at the KRAOC. Hazard quotients calculated from literature-derived toxicity reference values were below 1.0 at both the target and the reference Site based on the no-observed-adverse-effect level and the lowest-observed- adverse-effect level.
Robert O Wright - One of the best experts on this subject based on the ideXlab platform.
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the challenge posed to children s health by mixtures of toxic waste the tar creek Superfund Site as a case study
Pediatric Clinics of North America, 2007Co-Authors: Howard Hu, Robert O Wright, Jonathan P. ShineAbstract:In the United States, many of the millions of tons of hazardous wastes that have been produced since World War II have accumulated in Sites throughout the nation. Citizen concern about the extent of this problem led Congress to establish the Superfund Program in 1980 to locate, investigate, and clean up the worst Sites nationwide. Most such waste exists as a complex mixture of many substances. This article discusses the issue of toxic mixtures and children's health by focusing on the specific example of mining waste at the Tar Creek Superfund Site in Northeast Oklahoma.
Arianne M Neigh - One of the best experts on this subject based on the ideXlab platform.
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productivity of tree swallows tachycineta bicolor exposed to pcbs at the kalamazoo river Superfund Site
Journal of Toxicology and Environmental Health, 2006Co-Authors: Arianne M Neigh, Monica A Maccarroll, Matthew J Zwiernik, Alan L Blankenship, Paul D. Jones, John L. Newsted, John P GiesyAbstract:A 123-km stretch of the Kalamazoo River in Michigan, was designated a Superfund Site in 1990 due to historical releases of effluent containing polychlorinated biphenyl (PCB)-contaminated paper waste. Risk to bird species in the river ecosystem was evaluated using the tree swallow (Tachycineta bicolor) as a monitor for possible effects due to PCB exposure at two nesting locations, one in the Superfund Site and one in an upstream reference location that is less contaminated with PCBs. In 2 of the 3 years of the study, clutch size at the contaminated location was 3.7 ± 1.4 and 4.8 ± 0.73 eggs per nest (mean ± SD), which was significantly less than the clutch size at the reference location (5.0 ± 1.1 and 5.3 ± 1.1 eggs per nest). However, there were no statistically significant differences in fledging success, predicted brood size, predicted number of fledglings, or growth of nestlings between the Kalamazoo River Superfund Site and an upstream reference location with lesser concentrations of PCBs in the sedim...
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tree swallow tachycineta bicolor exposure to polychlorinated biphenyls at the kalamazoo river Superfund Site michigan usa
Environmental Toxicology and Chemistry, 2006Co-Authors: Arianne M Neigh, Matthew J Zwiernik, Patrick W Bradley, Cyrus S Park, Alan L Blankenship, Paul D. Jones, John L. Newsted, John P GiesyAbstract:In 1990, a portion of the Kalamazoo River in Michigan, USA, was designated a Superfund Site because of the presence of polychlorinated biphenyls (PCBs) in the sediment and floodplain soils. During a four-year period from 2000 to 2003, several avian species were monitored for reproductive effects and concentrations of PCBs in tissues attributed to food chain transfer from contaminated sediments. The tree swallow (Tachycineta bicolor) was chosen as a model receptor for contamination of passerine species. A top-down methodology was used to evaluate the bioaccumulation of PCBs, including non-ortho and mono-ortho congeners, in tree swallow eggs, nestlings, and adults at the Kalamazoo River area of concern (KRAOC) and at an upstream reference Site. Generally, a sixfold difference in tissue concentrations of total PCBs was observed between the two Sites with concentrations in eggs and nestlings at the KRAOC ranging from 0.95 to 15 mg PCB/g wet weight. Concentrations of 2,3,7,8- tetrachlorodibenzo-p-dioxin equivalents (TEQsWHO2Avian) for PCBs, based on bird-specific World Health Organization toxic equiv- alence factors, were 10- to 30-fold greater in the KRAOC than at the reference location. Egg and nestling TEQsWHO2Avian ranged from 0.21 to 2.4 ng TEQ/g wet weight at the KRAOC. Hazard quotients calculated from literature-derived toxicity reference values were below 1.0 at both the target and the reference Site based on the no-observed-adverse-effect level and the lowest-observed- adverse-effect level.
Karen Mcbee - One of the best experts on this subject based on the ideXlab platform.
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Population Demographics of Red-Eared Slider Turtles (Trachemys scripta) from Tar Creek Superfund Site
Journal of Herpetology, 2010Co-Authors: Kimberly A. Hays, Karen McbeeAbstract:Mining can result in severe physical and chemical alterations of landscapes. Tar Creek Superfund Site, located in northeastern Oklahoma, was mined extensively for lead and zinc from the early 1900s until the 1970s and remains heavily damaged. We investigated the ecology of Red-Eared Slider Turtles (Trachemys scripta) from Beaver Creek within Tar Creek Superfund Site and two reference Sites, Lake Carl Blackwell and Sequoyah National Wildlife Refuge. We measured parameters, including body size, sex ratios, sexual dimorphism indices, and recapture and survival rates. Sex ratios were female biased at Tar Creek Superfund Site and Lake Carl Blackwell and male biased at Sequoyah National Wildlife Refuge. Degree of sexual size dimorphism differed significantly among the three Sites. Male T. scripta were significantly larger at Lake Carl Blackwell than at Tar Creek Superfund Site and Sequoyah National Wildlife Refuge. Females from Tar Creek Superfund Site were significantly larger than females from Lake Carl Blackwell. Survival and recapture rates did not differ significantly among the Sites. Overall, we found no significant, consistent differences in population demographics of T. scripta inhabiting mined and unmined Sites.
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Ecological Characteristics of Small Mammal Communities at a Superfund Site
The American Midland Naturalist, 2009Co-Authors: Kendra L. Phelps, Karen McbeeAbstract:Wildlife species can serve as biomonitors of environmental health and are prognostic of ecotoxicological consequences when contaminants are introduced into the environment. Small mammals, particularly rodents, comprise the majority of indicator species used in terrestrial biomonitoring studies; however, many biomonitoring studies address acute effects over relatively short periods. We still know little regarding effects of chronic exposure to contaminants on small mammals. The overall goal of this study was to determine ecological characteristics of small mammal communities inhabiting a heavy metal contaminated Site, Tar Creek Superfund Site, compared to reference Sites located in northeastern Oklahoma over a 2 y timeframe. Primary hazardous materials present at Tar Creek Superfund Site include lead, zinc and cadmium. Mark-recapture techniques were employed to test the hypothesis that structure and composition of small mammal communities inhabiting this contaminated Site would be significantly altered compared to uncontaminated reference Sites. Contaminated and reference Sites were similar in vegetation compositional characteristics. Small mammal communities inhabiting Tar Creek Superfund Site had reduced species diversity, including richness and evenness, compared to reference Sites. Furthermore, communities within Tar Creek Superfund Site were dominated by a single species, Peromyscus leucopus (white-footed mouse). Species composition was different between contaminated Sites and reference Sites as evidenced by detrended correspondence analysis, with contaminated Sites being more similar to each other than to either reference Site. No direct link between Site contamination and disparities among most ecological characteristics could be established.
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Flow cytometric analysis of red-eared slider turtles (Trachemys scripta) from Tar Creek Superfund Site
Ecotoxicology, 2007Co-Authors: Kimberly A. Hays, Karen McbeeAbstract:Tar Creek Superfund Site (TCSFS) was heavily mined from the 1890s to 1970 and currently is contaminated with lead, zinc, and cadmium. Flow cytometry (FCM) was used to measure variation in nuclear DNA content of red blood cells collected from Trachemys scripta living within TCSFS and reference Sites, Lake Carl Blackwell (LCB) and Sequoyah National Wildlife Refuge (SNWR). We also used atomic absorption spectrometry to measure Pb in blood and carapace and Cd in blood samples of turtles from TCSFS and SNWR. Mean coefficients of variation around the G_1 peak ranged from 5.33 to 5.48 and showed no significant difference between contaminated and reference populations; however, there was a significantly higher frequency of aneuploidy at TCSFS when compared with both reference populations. Blood Pb levels were not significantly different between TCSFS and SNWR populations. Pb levels in carapace samples did not differ significantly between Sites; however, Pb levels were higher in carapace than blood for both populations. Blood Cd was significantly higher in animals at TCSFS than SNWR.
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Chromosomal aberrations in Sigmodon hispidus from a Superfund Site
1995Co-Authors: B. Bowers, Karen Mcbee, S. Burks, Robert L Lochmiller, Carl QuallsAbstract:Cotton rats (Sigmodon hispidus) were collected from an EPA Superfund Site located on an abandoned oil refinery. Three trapping grids were located on the refinery and three similar grids were located at uncontaminated localities which served as reference Sites. Bone marrow metaphase chromosome preparations were examined for chromosomal damage. For each individual, 50 cells were scored for six classes of chromosomal lesions. For the fall 1991 trapping period, mean number of aberrant cells per individual was 2.33, 0.85, and 1.50 for the three Superfund grids., Mean number of aberrant cells per individual was 2.55, 2.55, and 2.12 from the reference grids. Mean number of lesions per cell was 2.77, 0.86, and 1.9 from the Superfund grids, and 3.55, 2.77, and 2.50 from the reference grids. For the spring 1992 trapping period, more damage was observed in animals from both Superfund and reference Sites; however, animals from Superfund grids had more damage than animals from reference grids. Mean number of aberrant cells per individual was 3.50, 3.25, and 3.70 from the Superfund grids, and 2.40, 2.11, and 1.40 from the reference grids. Mean number of lesions per cell was 4.80, 4.25, and 5.50 from the Superfund grids, and 2.60, 2.33, andmore » 1.50 from the reference grids. These data suggest animals may be more susceptible to chromosomal damage during winter months, and animals from the Superfund grids appear to be more severely affected than animals from reference grids.« less
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Genetic effects of petrochemical pollutants on cotton rats in mesocosms at a Superfund Site
1995Co-Authors: Karen Mcbee, S. Burks, Robert L Lochmiller, C. Butchko, T. Propst, Carl QuallsAbstract:Equal numbers of male and female juvenile cotton rats (Siamodon hispidus) were introduced into mesocosms placed on three areas of an abandoned oil refinery now designated as a Superfund Site located in southwestern Oklahoma. Cotton rats were also housed in mesocosms on three uncontaminated reference Sites. After two eight-week exposure periods and one four-week exposure period, animals were examined for chromosomal aberrations in bone marrow cells. The predominant type of aberration observed in animals from all mesocosms was chromatid breaks. During the spring eight-week exposure period animals from mesocosms on reference Sites had higher numbers of aberrant cells and more 11 eight-week expo lesions per cell than did animals housed in mesocosms on the Superfund Site. During the fall eight-week exposure period and a later fall four-week exposure period, animals from Superfund Site mesocosms and reference mesocosms showed no differences in aberrant cells or lesions per cell. Animals from both Superfund and reference mesocosms showed significantly fewer aberrant cells and lesions per cell during the fall eight-week and fall four-week exposure periods than their counterparts from the spring eight-week exposure period.
John L. Newsted - One of the best experts on this subject based on the ideXlab platform.
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productivity of tree swallows tachycineta bicolor exposed to pcbs at the kalamazoo river Superfund Site
Journal of Toxicology and Environmental Health, 2006Co-Authors: Arianne M Neigh, Monica A Maccarroll, Matthew J Zwiernik, Alan L Blankenship, Paul D. Jones, John L. Newsted, John P GiesyAbstract:A 123-km stretch of the Kalamazoo River in Michigan, was designated a Superfund Site in 1990 due to historical releases of effluent containing polychlorinated biphenyl (PCB)-contaminated paper waste. Risk to bird species in the river ecosystem was evaluated using the tree swallow (Tachycineta bicolor) as a monitor for possible effects due to PCB exposure at two nesting locations, one in the Superfund Site and one in an upstream reference location that is less contaminated with PCBs. In 2 of the 3 years of the study, clutch size at the contaminated location was 3.7 ± 1.4 and 4.8 ± 0.73 eggs per nest (mean ± SD), which was significantly less than the clutch size at the reference location (5.0 ± 1.1 and 5.3 ± 1.1 eggs per nest). However, there were no statistically significant differences in fledging success, predicted brood size, predicted number of fledglings, or growth of nestlings between the Kalamazoo River Superfund Site and an upstream reference location with lesser concentrations of PCBs in the sedim...
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tree swallow tachycineta bicolor exposure to polychlorinated biphenyls at the kalamazoo river Superfund Site michigan usa
Environmental Toxicology and Chemistry, 2006Co-Authors: Arianne M Neigh, Matthew J Zwiernik, Patrick W Bradley, Cyrus S Park, Alan L Blankenship, Paul D. Jones, John L. Newsted, John P GiesyAbstract:In 1990, a portion of the Kalamazoo River in Michigan, USA, was designated a Superfund Site because of the presence of polychlorinated biphenyls (PCBs) in the sediment and floodplain soils. During a four-year period from 2000 to 2003, several avian species were monitored for reproductive effects and concentrations of PCBs in tissues attributed to food chain transfer from contaminated sediments. The tree swallow (Tachycineta bicolor) was chosen as a model receptor for contamination of passerine species. A top-down methodology was used to evaluate the bioaccumulation of PCBs, including non-ortho and mono-ortho congeners, in tree swallow eggs, nestlings, and adults at the Kalamazoo River area of concern (KRAOC) and at an upstream reference Site. Generally, a sixfold difference in tissue concentrations of total PCBs was observed between the two Sites with concentrations in eggs and nestlings at the KRAOC ranging from 0.95 to 15 mg PCB/g wet weight. Concentrations of 2,3,7,8- tetrachlorodibenzo-p-dioxin equivalents (TEQsWHO2Avian) for PCBs, based on bird-specific World Health Organization toxic equiv- alence factors, were 10- to 30-fold greater in the KRAOC than at the reference location. Egg and nestling TEQsWHO2Avian ranged from 0.21 to 2.4 ng TEQ/g wet weight at the KRAOC. Hazard quotients calculated from literature-derived toxicity reference values were below 1.0 at both the target and the reference Site based on the no-observed-adverse-effect level and the lowest-observed- adverse-effect level.