Archives of Environmental Contamination and Toxicology, Nov 25, 2015
Total mercury (THg) and selenium (Se) were analyzed by Inductively Coupled Plasma Mass Spectromet... more Total mercury (THg) and selenium (Se) were analyzed by Inductively Coupled Plasma Mass Spectrometry in 11 internal and external tissues and stomach contents from 23 brown trout, Salmo trutta, of a 22.9-km reach of a high-gradient stream (upper Fountain Creek) in Colorado, USA, impacted by coal-fired power plants, shale deposits, and urbanization. Trout and water were sampled from four sites ranging from 2335 to 1818 m elevation. Lengths, weights, and ages of fish between pairs of the four sites were not significantly different. The dry weight (dw) to wet weight (ww) conversion factor for each tissue was calculated with egg-ovary highest at 0.379 and epaxial muscle fourth highest at 0.223. THg and Se in stomach contents indicated diet and not ambient water was the major source of Hg and Se bioaccumulated. Mean THg ww in kidney was 40.33 µg/kg, and epaxial muscle second highest at 36.76 µg/kg. None of the tissues exceeded the human critical threshold for Hg. However, all 23 trout had at least one tissue type that exceeded 0.02 mg/kg THg ww for birds, and four trout tissues exceeded 0.1 mg/kg THg ww for mammals, indicating that piscivorous mammals and birds should be monitored. Se concentrations in tissues varied depending on ww or dw listing. Mean Se dw in liver was higher than ovary at the uppermost site and the two lower sites. Liver tissue, in addition to egg-ovary, should be utilized as an indicator tissue for Se toxicity.
Concentrations of heavy metals in sediments and soils deposited along the floodplain of the Clark... more Concentrations of heavy metals in sediments and soils deposited along the floodplain of the Clark Fork River, within the boundaries of the Grant-Kohrs Ranch National Historic Site, have exceeded those typically found in uncontaminated soils. Upstream mining activities along the Clark Fork River in the Deer Lodge Valley, Montana, have produced substantial quantities of mine waste which have been deposited throughout the watershed. Releases and re-releases of these contaminated substances continue to occur, and appear to be preventing the germination and establishment of critical riparian plant species and depressing soil microbe activity. Slickens, bare spots devoid of all vegetation, occur frequently in the floodplain along the Clark Fork River. This research investigates the toxicity of slicken soils using a series of earthworm (Eisenia foetida andrei) survival and behavior tests. In dilution tests, earthworm survival was reduced significantly in as little as 12.5% slicken soil. Results from earthworm behavior tests currently being conducted using non-lethal slicken soil dilutions will also be presented.
Transactions of the American Fisheries Society, 1975
... SALINITY FOR FLOW-THROUGH BIOASSAYS. IT WAS USED SUCCESSFULLY IN PESTICIDE BIOASSAYS AND REQU... more ... SALINITY FOR FLOW-THROUGH BIOASSAYS. IT WAS USED SUCCESSFULLY IN PESTICIDE BIOASSAYS AND REQUIRED LITTLE MAINTENANCE. (KLEIN) SW 3010 Identification of pollutants; SW 5040 Data acquisition.
Wilson`s Creek is a tributary of the James River in southwestern Missouri that flows from the urb... more Wilson`s Creek is a tributary of the James River in southwestern Missouri that flows from the urban area of Springfield through Wilson`s Creek National Battlefield Park. Previous investigators identified poor water quality in Wilson`s Creek and reported several fish kill incidences in the watershed. Water quality problems are complicated by a marked increase in urbanization within the watershed and the interaction of surface water with a complex karst groundwater system. The objective of this study was to use macroinvertebrate and fish communities, single species bioassays, and toxicity identification procedures (TIEs) to identify contaminants and their sources. Macroinvertebrate and fish indices as well as Ceriodaphnia dubia test indicated upstream contaminants were affecting water quality in the park. Toxicity identification procedures suggested that metals were likely responsible for the toxicity. Four samples from Wilson`s Creek showed zinc exceeding 25 parts-per-billion (ppb); ...
Archives of Environmental Contamination and Toxicology, Nov 25, 2015
Total mercury (THg) and selenium (Se) were analyzed by Inductively Coupled Plasma Mass Spectromet... more Total mercury (THg) and selenium (Se) were analyzed by Inductively Coupled Plasma Mass Spectrometry in 11 internal and external tissues and stomach contents from 23 brown trout, Salmo trutta, of a 22.9-km reach of a high-gradient stream (upper Fountain Creek) in Colorado, USA, impacted by coal-fired power plants, shale deposits, and urbanization. Trout and water were sampled from four sites ranging from 2335 to 1818 m elevation. Lengths, weights, and ages of fish between pairs of the four sites were not significantly different. The dry weight (dw) to wet weight (ww) conversion factor for each tissue was calculated with egg-ovary highest at 0.379 and epaxial muscle fourth highest at 0.223. THg and Se in stomach contents indicated diet and not ambient water was the major source of Hg and Se bioaccumulated. Mean THg ww in kidney was 40.33 µg/kg, and epaxial muscle second highest at 36.76 µg/kg. None of the tissues exceeded the human critical threshold for Hg. However, all 23 trout had at least one tissue type that exceeded 0.02 mg/kg THg ww for birds, and four trout tissues exceeded 0.1 mg/kg THg ww for mammals, indicating that piscivorous mammals and birds should be monitored. Se concentrations in tissues varied depending on ww or dw listing. Mean Se dw in liver was higher than ovary at the uppermost site and the two lower sites. Liver tissue, in addition to egg-ovary, should be utilized as an indicator tissue for Se toxicity.
Concentrations of heavy metals in sediments and soils deposited along the floodplain of the Clark... more Concentrations of heavy metals in sediments and soils deposited along the floodplain of the Clark Fork River, within the boundaries of the Grant-Kohrs Ranch National Historic Site, have exceeded those typically found in uncontaminated soils. Upstream mining activities along the Clark Fork River in the Deer Lodge Valley, Montana, have produced substantial quantities of mine waste which have been deposited throughout the watershed. Releases and re-releases of these contaminated substances continue to occur, and appear to be preventing the germination and establishment of critical riparian plant species and depressing soil microbe activity. Slickens, bare spots devoid of all vegetation, occur frequently in the floodplain along the Clark Fork River. This research investigates the toxicity of slicken soils using a series of earthworm (Eisenia foetida andrei) survival and behavior tests. In dilution tests, earthworm survival was reduced significantly in as little as 12.5% slicken soil. Results from earthworm behavior tests currently being conducted using non-lethal slicken soil dilutions will also be presented.
Transactions of the American Fisheries Society, 1975
... SALINITY FOR FLOW-THROUGH BIOASSAYS. IT WAS USED SUCCESSFULLY IN PESTICIDE BIOASSAYS AND REQU... more ... SALINITY FOR FLOW-THROUGH BIOASSAYS. IT WAS USED SUCCESSFULLY IN PESTICIDE BIOASSAYS AND REQUIRED LITTLE MAINTENANCE. (KLEIN) SW 3010 Identification of pollutants; SW 5040 Data acquisition.
Wilson`s Creek is a tributary of the James River in southwestern Missouri that flows from the urb... more Wilson`s Creek is a tributary of the James River in southwestern Missouri that flows from the urban area of Springfield through Wilson`s Creek National Battlefield Park. Previous investigators identified poor water quality in Wilson`s Creek and reported several fish kill incidences in the watershed. Water quality problems are complicated by a marked increase in urbanization within the watershed and the interaction of surface water with a complex karst groundwater system. The objective of this study was to use macroinvertebrate and fish communities, single species bioassays, and toxicity identification procedures (TIEs) to identify contaminants and their sources. Macroinvertebrate and fish indices as well as Ceriodaphnia dubia test indicated upstream contaminants were affecting water quality in the park. Toxicity identification procedures suggested that metals were likely responsible for the toxicity. Four samples from Wilson`s Creek showed zinc exceeding 25 parts-per-billion (ppb); ...
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