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Justin D Congdon - One of the best experts on this subject based on the ideXlab platform.
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accumulation and selective maternal transfer of contaminants in the turtle trachemys scripta associated with coal ash deposition
Archives of Environmental Contamination and Toxicology, 2001Co-Authors: R D Nagle, Christopher L Rowe, Justin D CongdonAbstract:Coal combustion wastes are enriched in a number of potentially toxic compounds and may pose risks to biota ex- posed to the wastes. Slider turtles (Trachemys scripta) are common inhabitants of coal ash settling basins in South Caro- lina, USA, where they feed on contaminated prey items and accumulate high levels of potentially toxic compounds in their tissues. Furthermore, female sliders sometimes nest in contam- inated spill piles and thus may expose embryos to contaminated soils. We examined two potential pathways by which female T. scripta may influence the survivorship and quality of their offspring in a contaminated habitat: (1) nesting in contaminated soil and (2) maternal transfer of pollutants. Eggs were collected from turtles captured in coal ash-Polluted or unPolluted Sites; individual clutches were incubated in both ash-contaminated and uncontaminated soil in outdoor, artificial nests. Incubation in contaminated soil was associated with reduced embryo sur- vivorship. Adult females from the Polluted Site accumulated high levels of As, Cd, Cr, and Se in their tissues, yet Se was the only element transferred maternally to hatchlings at relatively high levels. Hatchlings from Polluted-Site females exhibited reduced O2 consumption rates compared to hatchlings from reference Sites. Relatively high levels of Se transferred to hatchlings by females at the ash-Polluted Site might contribute to the observed differences in hatchling physiology.
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elevated trace element concentrations and standard metabolic rate in banded water snakes nerodia fasciata exposed to coal combustion wastes
Environmental Toxicology and Chemistry, 1999Co-Authors: William A Hopkins, Christopher L Rowe, Justin D CongdonAbstract:Trace element concentrations in banded water snakes, Nerodia fasciata,and representative prey items from a Site Polluted by coal combustion wastes were compared with concentrations in conspecifics from a nearby reference Site. Water snakes accumulated high concentrations of trace elements, especially arsenic (As) and selenium (Se), in the Polluted habitat. In addition to being exposed to contaminants in water and sediments, snakes in the Polluted Site are exposed to contaminants by ingesting prey items that have elevated whole-body concentrations of trace elements, including As, cadmium (Cd), and Se. Snakes from the Polluted Site exhibited mean standard metabolic rates (SMR) 32% higher than snakes from the reference Site. As a result, snakes from the Polluted Site appear to have elevated allocation of energy to maintenance and theoretically should have less energy available for growth, reproduction, and storage. Our findings are consistent with physiological responses recently documented in other organisms from the Polluted Site. We hypothesize that long-term exposure to coal ash-derived trace elements and the resultant accumulation of some elements are responsible for observed increases in SMR. Keywords—Coal combustion wastes Snakes Trace elements Standard metabolic rate
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elevated maintenance costs in an anuran rana catesbeiana exposed to a mixture of trace elements during the embryonic and early larval periods
Physiological and Biochemical Zoology, 1998Co-Authors: Christopher L Rowe, Owen M Kinney, Roy D Nagle, Justin D CongdonAbstract:ABSTRACT We investigated the relationship between maintenance costs (standard metabolic rates, measured as O2 consumption at rest) in tadpoles of the bullfrog, Rana catesbeiana, and exposure to contaminants in a coal ash‐Polluted habitat (characterized by a variety of trace elements). We compared metabolic rates of tadpoles collected from the Polluted Site with those from an unPolluted reference pond. Tadpoles collected in the Polluted Site had 40%–97% higher standard metabolic rates than those collected from the reference pond. We also reciprocally transplanted eggs of the bullfrog between the Polluted Site and another reference pond and compared standard metabolic rates of tadpoles at 25 and 80 d posthatching. Metabolic rates of tadpoles raised in the Polluted Site were from 39% to 175% higher than those raised in a reference pond, depending on tadpole age and temperature at which metabolic rates were measured. There were no effects of Site of origin of the eggs (Polluted or unPolluted) on metabolic rat...
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increased circulating levels of testosterone and corticosterone in southern toads bufo terrestris exposed to coal combustion waste
General and Comparative Endocrinology, 1997Co-Authors: William A Hopkins, Mary T Mendonca, Justin D CongdonAbstract:This study describes an interrenal stress response in adult toads,Bufo terrestris,after exposure to coal combustion waste (characterized by a variety of trace elements). In the first portion of this study, free-ranging male toads captured at the coal ash Polluted Site exhibited significantly higher circulating levels of corticosterone (B) in both June/July and August than conspecifics captured at uncontaminated Sites. In addition, both calling and noncalling males from the Polluted Site had higher B levels than conspecifics engaged in the same behaviors at reference Sites. Testosterone levels were elevated in toads from the Polluted Site, regardless of capture month or behavioral state, suggesting altered androgen production, utilization, and/or clearance. In the second portion of this study, male toads from reference Sites were transplanted to enclosures at the Polluted Site or an uncontaminated Site. Toads held at the Polluted Site exhibited significant increases in B after 10 days of exposure compared to toads held at the reference Site. B levels remained significantly elevated in toads transplanted to the Polluted Site after 12 weeks. We hypothesize that high concentrations of various trace elements in the Polluted Site are responsible for these hormonal responses.
Christopher L Rowe - One of the best experts on this subject based on the ideXlab platform.
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accumulation and selective maternal transfer of contaminants in the turtle trachemys scripta associated with coal ash deposition
Archives of Environmental Contamination and Toxicology, 2001Co-Authors: R D Nagle, Christopher L Rowe, Justin D CongdonAbstract:Coal combustion wastes are enriched in a number of potentially toxic compounds and may pose risks to biota ex- posed to the wastes. Slider turtles (Trachemys scripta) are common inhabitants of coal ash settling basins in South Caro- lina, USA, where they feed on contaminated prey items and accumulate high levels of potentially toxic compounds in their tissues. Furthermore, female sliders sometimes nest in contam- inated spill piles and thus may expose embryos to contaminated soils. We examined two potential pathways by which female T. scripta may influence the survivorship and quality of their offspring in a contaminated habitat: (1) nesting in contaminated soil and (2) maternal transfer of pollutants. Eggs were collected from turtles captured in coal ash-Polluted or unPolluted Sites; individual clutches were incubated in both ash-contaminated and uncontaminated soil in outdoor, artificial nests. Incubation in contaminated soil was associated with reduced embryo sur- vivorship. Adult females from the Polluted Site accumulated high levels of As, Cd, Cr, and Se in their tissues, yet Se was the only element transferred maternally to hatchlings at relatively high levels. Hatchlings from Polluted-Site females exhibited reduced O2 consumption rates compared to hatchlings from reference Sites. Relatively high levels of Se transferred to hatchlings by females at the ash-Polluted Site might contribute to the observed differences in hatchling physiology.
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elevated trace element concentrations and standard metabolic rate in banded water snakes nerodia fasciata exposed to coal combustion wastes
Environmental Toxicology and Chemistry, 1999Co-Authors: William A Hopkins, Christopher L Rowe, Justin D CongdonAbstract:Trace element concentrations in banded water snakes, Nerodia fasciata,and representative prey items from a Site Polluted by coal combustion wastes were compared with concentrations in conspecifics from a nearby reference Site. Water snakes accumulated high concentrations of trace elements, especially arsenic (As) and selenium (Se), in the Polluted habitat. In addition to being exposed to contaminants in water and sediments, snakes in the Polluted Site are exposed to contaminants by ingesting prey items that have elevated whole-body concentrations of trace elements, including As, cadmium (Cd), and Se. Snakes from the Polluted Site exhibited mean standard metabolic rates (SMR) 32% higher than snakes from the reference Site. As a result, snakes from the Polluted Site appear to have elevated allocation of energy to maintenance and theoretically should have less energy available for growth, reproduction, and storage. Our findings are consistent with physiological responses recently documented in other organisms from the Polluted Site. We hypothesize that long-term exposure to coal ash-derived trace elements and the resultant accumulation of some elements are responsible for observed increases in SMR. Keywords—Coal combustion wastes Snakes Trace elements Standard metabolic rate
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elevated standard metabolic rate in a freshwater shrimp palaemonetes paludosus exposed to trace element rich coal combustion waste
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 1998Co-Authors: Christopher L RoweAbstract:I conducted a transplant experiment to determine whether standard metabolic rate (SMR) of a freshwater shrimp (Palaemonetes paludosus) would be affected by exposure to trace element-enriched coal combustion waste (`coal ash'). Shrimp were transplanted into replicate cages in a coal ash-Polluted Site and a reference Site for 8 months. The coal ash-Polluted Site was characterized by elevated sediment concentrations of As, Cd, Cr, Cu, Ni, Pb, and Se compared to sediments in the reference Site. After 8 months in the study Sites, shrimp in the Polluted Site appeared to have accumulated As, Cd, and Se from the habitat, but there were no differences in survival between the study Sites. However, mean SMR of shrimp (measured as O2 consumption at rest) held in the Polluted Site was 51% higher than mean SMR of shrimp held in the reference Site. The elevation in SMR indicates that the energetic costs of maintenance are greater for shrimp chronically exposed to the coal-ash Polluted environment than shrimp in the reference Site. It is likely, therefore, that other physiological or behavioral processes may be modified in the pollution-exposed individuals to compensate for the increased energy demands for maintenance. Recent studies have reported similar elevations in SMR in an amphibian and a reptile chronically exposed to coal ash. Analogous physiological responses in such taxonomically diverse animals (a crustacean, an amphibian, and a reptile) indicate that elevated SMR may be a general response by many types of organisms exposed to the mixture of trace elements characteristic of coal ash. The relationships among pollution-induced elevations in maintenance expenditures, long-term health of individuals, and population-level parameters require further attention.
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elevated maintenance costs in an anuran rana catesbeiana exposed to a mixture of trace elements during the embryonic and early larval periods
Physiological and Biochemical Zoology, 1998Co-Authors: Christopher L Rowe, Owen M Kinney, Roy D Nagle, Justin D CongdonAbstract:ABSTRACT We investigated the relationship between maintenance costs (standard metabolic rates, measured as O2 consumption at rest) in tadpoles of the bullfrog, Rana catesbeiana, and exposure to contaminants in a coal ash‐Polluted habitat (characterized by a variety of trace elements). We compared metabolic rates of tadpoles collected from the Polluted Site with those from an unPolluted reference pond. Tadpoles collected in the Polluted Site had 40%–97% higher standard metabolic rates than those collected from the reference pond. We also reciprocally transplanted eggs of the bullfrog between the Polluted Site and another reference pond and compared standard metabolic rates of tadpoles at 25 and 80 d posthatching. Metabolic rates of tadpoles raised in the Polluted Site were from 39% to 175% higher than those raised in a reference pond, depending on tadpole age and temperature at which metabolic rates were measured. There were no effects of Site of origin of the eggs (Polluted or unPolluted) on metabolic rat...
Jaco Vangronsveld - One of the best experts on this subject based on the ideXlab platform.
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fenton mediated biodegradation of chlorendic acid a highly chlorinated organic pollutant by fungi isolated from a Polluted Site
Frontiers in Microbiology, 2019Co-Authors: Inge Jambon, Sofie Thijs, Francois Rineau, Nele Weyens, Robert Carleer, Pieter Samyn, Jaco Vangronsveld, Giselle TorresfarradaAbstract:Chlorendic acid is a recalcitrant, highly chlorinated organic pollutant for which no microbial degrader has yet been identified. To address this knowledge gap, fungi were isolated from bulk soil, rhizosphere, and roots of the common bent (Agrostis capillaris) and the hybrid poplar (Populus deltoides x (Populus trichocarpa x Populus deltoides) cv. Grimminge), both of which grow on a chlorendic acid Polluted Site in Belgium. Isolates were taxonomically identified and phenotypically screened for chlorendic acid degradation. Several fungal isolates could degrade chlorendic acid in liquid media up to 45%. The chlorendic acid degrading fungal isolates produced higher levels of hydroxyl radicals when exposed to the pollutant when compared to non-exposed controls, suggesting that the oxidative degradation of chlorendic acid occurs through production of Fenton-mediated hydroxyl radicals. In addition, the isolated Ascomycete Penicillium sp. 1D-2a degraded 58% of the original chlorendic acid concentration in the soil after 28 days. This study demonstrates that the presence of fungi in a chlorendic acid Polluted soil can degrade this highly chlorinated organic pollutant. These results indicate that recalcitrant, seemingly non-biologically degradable organic pollutants, such as chlorendic acid, can be remediated by using bioremediation, which opens new perspectives for in-situ bioremediation.
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hydrocarbon degradation potential and plant growth promoting activity of culturable endophytic bacteria of lotus corniculatus and oenothera biennis from a long term Polluted Site
Environmental Science and Pollution Research, 2017Co-Authors: Malgorzata Pawlik, Sofie Thijs, Jaco Vangronsveld, Barbara Cania, Zofia PiotrowskasegetAbstract:Many endophytic bacteria exert beneficial effects on their host, but still little is known about the bacteria associated with plants growing in areas heavily Polluted by hydrocarbons. The aim of the study was characterization of culturable hydrocarbon-degrading endophytic bacteria associated with Lotus corniculatus L. and Oenothera biennis L. collected in long-term petroleum hydrocarbon-Polluted Site using culture-dependent and molecular approaches. A total of 26 hydrocarbon-degrading endophytes from these plants were isolated. Phylogenetic analyses classified the isolates into the phyla Proteobacteria and Actinobacteria. The majority of strains belonged to the genera Rhizobium, Pseudomonas, Stenotrophomonas, and Rhodococcus. More than 90% of the isolates could grow on medium with diesel oil, approximately 20% could use n-hexadecane as a sole carbon and energy source. PCR analysis revealed that 40% of the isolates possessed the P450 gene encoding for cytochrome P450-type alkane hydroxylase (CYP153). In in vitro tests, all endophytic strains demonstrated a wide range of plant growth-promoting traits such as production of indole-3-acetic acid, hydrogen cyanide, siderophores, and phosphate solubilization. More than 40% of the bacteria carried the gene encoding for the 1-aminocyclopropane-1-carboxylic acid deaminase (acdS). Our study shows that the diversity of endophytic bacterial communities in tested plants was different. The results revealed also that the investigated plants were colonized by endophytic bacteria possessing plant growth-promoting features and a clear potential to degrade hydrocarbons. The properties of isolated endophytes indicate that they have the high potential to improve phytoremediation of petroleum hydrocarbon-Polluted soils.
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genetic variation and heavy metal tolerance in the ectomycorrhizal basidiomycete suillus luteus
New Phytologist, 2000Co-Authors: Jan V. Colpaert, Philippe Vandenkoornhuyse, Kristin Adriaensen, Jaco VangronsveldAbstract:Twenty-one isolates of the ectomycorrhizal fungus Suillus luteus were screened for their tolerance to the heavy metals Zn, Cd, Cu and Ni, measured as inhibition of radial growth and biomass production. Two populations from even-aged pine stands were investigated: 10 isolates were obtained from an area Polluted with high levels of Zn, Cd and Cu, and 11 isolates were obtained from a control population located in a nearby unPolluted area. RFLP patterns of the internal transcribed spacer region of the isolates confirmed the morphological identification of the carpophores. All isolates were maintained on basic medium without elevated metals to avoid phenotypically acquired metal tolerance. The in vitro Zn and Cd tolerance of the S. luteus isolates from the Polluted habitat were significantly higher than the tolerances measured in the isolates from the nonPolluted Site. This observation suggests that the elevated soil metal concentrations might be responsible for the evolution of adaptive Zn and Cd tolerance. Tolerance was maintained in an isolate not exposed to elevated metals for 3 yr. The two S. luteus populations did not differ in tolerance to Cu and Ni. The mechanisms for the adaptive Zn and Cd tolerance are not identical as there was no correlation between response to the two metals; the most Zn-tolerant isolate was the most sensitive for Cd in the metal-tolerant population. Zinc did not accumulate in basidiocarp tissue, whereas Cd levels in basidiocarps were significantly higher in the population on the Polluted Site. Inter-simple sequence-repeat fingerprints showed that 90% of the isolates were from different individuals. The genetic variation in the population from the unPolluted Site was considerably larger than that observed at the Polluted Site.
Graziella Berta - One of the best experts on this subject based on the ideXlab platform.
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screening for heavy metal accumulators amongst autochtonous plants in a Polluted Site in italy
Ecotoxicology and Environmental Safety, 2010Co-Authors: Nadia Massa, Flora Andreucci, Monica Poli, Maurizio Aceto, Roberto Barbato, Graziella BertaAbstract:The Site around ACNA factory (Northern Italy) is characterized by multi-metal contamination, therefore it can be considered as a source of autochthonous plants able to tolerate or accumulate heavy metals (HMs). The hill A5, a waste dump of the chemical factory, was chosen as the study area, in order to assess the metal accumulation ability of the vegetation growing under HM stress. The plant species, biodiversity and health were related to the concentration of HMs in four areas of the hill A5, and to the metal accumulation in shoots and roots. Uptake of HMs occurred at different extent in the various plant species and differed according to the considered organ and metal. Polygonum aviculare hyperaccumulated Hg in the shoot suggesting its possible exploitation in phytoextraction. A number of species, that can be useful in phytoremediation plans, accumulated simultaneously more than two heavy metals both in the shoot and in the root.
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microbiological polyphasic approach for soil health evaluation in an italian Polluted Site
Science of The Total Environment, 2009Co-Authors: Arturo Fabiani, Elisa Gamalero, Gian Paolo Cossa, M Castaldini, Chiara Musso, M Pagliai, Graziella BertaAbstract:article i nfo The use of microorganisms as bioindicators of soil health is quite a new feature, rarely considered for the soil health evaluation in chronically-Polluted industrial Sites, and still suffering of the bias related to the technique applied. In this work we applied a microbiological polyphasic approach, relying on soil indigenous microorganisms as bioindicators and combining culture-dependent and -independent methods, in order to evaluate soil health of four Sites (1a, 1b, 2a and 2b) inside a chemical factory with a centenary activity. Functional as well as structural aspects were comprehensively considered. Results were related to the kind of pollutants found in each Site. Heavy metal pollution was recorded in Sites 1b and 2b, while both organic and inorganic substances were detected in Sites 1a and 2a. Based on the chemical and physical properties of the four soils, Site 1b and 2b grouped together, while 1a and 2a were separated from the others. The density of the culturable bacteria was very low in Site 2a, where only Gram-positive were found. According to the identification of culturable bacteria, Site 2a showed the lowest similarity with the other Sites. Microbial activity was detected only in Sites 1b and 2b. PCR-DGGE (Denaturing Gradient Gel Electrophoresis), was performed on the culturable, total and active microbial communities. Consistently with the identification of culturable bacterial strains, the molecular profile of the culturable fraction of Site 2a, was clearly separated from the molecular profiles of other Sites in cluster analysis. Molecular fingerprintings of the whole and active bacterial communities differed among the Sites, but clustered according to the pollutants present in each Site. The presence of possible key species in each Site has been discussed according to the whole and active species. Since the results obtained by microbiological analysis are consistent with the chemical data, we suggest that the use of this microbiological polyphasic approach and of microorganisms as intrinsic bioindicators, can be suitable for the evaluation of soil health.
William A Hopkins - One of the best experts on this subject based on the ideXlab platform.
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elevated trace element concentrations and standard metabolic rate in banded water snakes nerodia fasciata exposed to coal combustion wastes
Environmental Toxicology and Chemistry, 1999Co-Authors: William A Hopkins, Christopher L Rowe, Justin D CongdonAbstract:Trace element concentrations in banded water snakes, Nerodia fasciata,and representative prey items from a Site Polluted by coal combustion wastes were compared with concentrations in conspecifics from a nearby reference Site. Water snakes accumulated high concentrations of trace elements, especially arsenic (As) and selenium (Se), in the Polluted habitat. In addition to being exposed to contaminants in water and sediments, snakes in the Polluted Site are exposed to contaminants by ingesting prey items that have elevated whole-body concentrations of trace elements, including As, cadmium (Cd), and Se. Snakes from the Polluted Site exhibited mean standard metabolic rates (SMR) 32% higher than snakes from the reference Site. As a result, snakes from the Polluted Site appear to have elevated allocation of energy to maintenance and theoretically should have less energy available for growth, reproduction, and storage. Our findings are consistent with physiological responses recently documented in other organisms from the Polluted Site. We hypothesize that long-term exposure to coal ash-derived trace elements and the resultant accumulation of some elements are responsible for observed increases in SMR. Keywords—Coal combustion wastes Snakes Trace elements Standard metabolic rate
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increased circulating levels of testosterone and corticosterone in southern toads bufo terrestris exposed to coal combustion waste
General and Comparative Endocrinology, 1997Co-Authors: William A Hopkins, Mary T Mendonca, Justin D CongdonAbstract:This study describes an interrenal stress response in adult toads,Bufo terrestris,after exposure to coal combustion waste (characterized by a variety of trace elements). In the first portion of this study, free-ranging male toads captured at the coal ash Polluted Site exhibited significantly higher circulating levels of corticosterone (B) in both June/July and August than conspecifics captured at uncontaminated Sites. In addition, both calling and noncalling males from the Polluted Site had higher B levels than conspecifics engaged in the same behaviors at reference Sites. Testosterone levels were elevated in toads from the Polluted Site, regardless of capture month or behavioral state, suggesting altered androgen production, utilization, and/or clearance. In the second portion of this study, male toads from reference Sites were transplanted to enclosures at the Polluted Site or an uncontaminated Site. Toads held at the Polluted Site exhibited significant increases in B after 10 days of exposure compared to toads held at the reference Site. B levels remained significantly elevated in toads transplanted to the Polluted Site after 12 weeks. We hypothesize that high concentrations of various trace elements in the Polluted Site are responsible for these hormonal responses.
