The assessment of contaminated sediments is a difficult task due to the complex nature of the sed... more The assessment of contaminated sediments is a difficult task due to the complex nature of the sediment matrix and the potential for exposure of aquatic organisms to in-place contaminants via several routes. Differential species sensitivity also precludes the completion of a meaningful environmental assessment with only one species. Therefore, a battery of assays approach with the Microtox assay, 48 hr Daphnia magna and Ceriodaphnia dubia tests and a 10-day Chironomous tentans test was used to evaluate the toxicity of sediment pore waters and whole sediments from the Grand Calumet River-Indiana Harbor, Indiana area of concern. All toxicity tests indicated that the test fractions (pore water, whole sediment) from each study site were toxic to the test species. A toxic units (TU) approach was used to compare measured TU from each assay with calculated TU based on chemical analyses of pore waters and whole sediments and the results of reference toxicant tests. Based on the results of these analyses, ammonia, polycyclic aromatic hydrocarbons, metals, petroleum hydrocarbons, and bicarbonate ion appear to be the major contaminants of environmental significance to benthic invertebrates within the study area.
... supernatant. Preparation of multiple ali quants of the elutriate mixture was necessary to obt... more ... supernatant. Preparation of multiple ali quants of the elutriate mixture was necessary to obtain sufficient extract for subsequent testing. ... Ohio. Giesy, JP, Rosiu, CJ, Graney, RL, Newsted, JL, Benda, A., Kreis, Jr., RG, and Horvath, FJ, 1988a. ...
Ecotoxicology and Environmental Safety, Aug 1, 1993
The assessment of contaminated sediments is a difficult task due to the complex nature of the sed... more The assessment of contaminated sediments is a difficult task due to the complex nature of the sediment matrix and the potential for exposure of aquatic organisms to in-place contaminants via several routes. Differential species sensitivity also precludes the completion of a meaningful environmental assessment with only one species. Therefore, a battery of assays approach with the Microtox assay, 48 hr Daphnia magna and Ceriodaphnia dubia tests and a 10-day Chironomous tentans test was used to evaluate the toxicity of sediment pore waters and whole sediments from the Grand Calumet River-Indiana Harbor, Indiana area of concern. All toxicity tests indicated that the test fractions (pore water, whole sediment) from each study site were toxic to the test species. A toxic units (TU) approach was used to compare measured TU from each assay with calculated TU based on chemical analyses of pore waters and whole sediments and the results of reference toxicant tests. Based on the results of these analyses, ammonia, polycyclic aromatic hydrocarbons, metals, petroleum hydrocarbons, and bicarbonate ion appear to be the major contaminants of environmental significance to benthic invertebrates within the study area.
Environmental Toxicology and Chemistry, Nov 1, 1995
... 0730-7268(95)00150-6 Environmental Toxicology TOXICITY AND BIOACCUMULATION OF SEDIMENT-ASSOCI... more ... 0730-7268(95)00150-6 Environmental Toxicology TOXICITY AND BIOACCUMULATION OF SEDIMENT-ASSOCIATED CONTAMINANTS USING FRESHWATER INVERTEBRATES: AREVIEW OF METHODS AND APPLICATIONS ... Nickel 780 NT 12,160 Lead <16 NT 794 ...
Environmental Toxicology and Chemistry, Dec 1, 1996
Surficial sediments collected from Lake Michigan (N = 46) and the Virginian Province of the east ... more Surficial sediments collected from Lake Michigan (N = 46) and the Virginian Province of the east coast of the U.S. (N = 131) by the Environmental Monitoring and Assessment Program (EMAP) of the U.S. Environmental Protection Agency (EPA) were evaluated relative to a proposed approach to sediment quality criteria (SQC) for five metals (copper, cadmium, zinc, nickel, and lead). Concentrations of acid‒volatile sulfide (AVS), simultaneously extracted metals (SEM) from the AVS extraction, total metals, and total organic carbon were measured in the sediments. Interstitial pore‒water concentrations of the five metals also were measured in the freshwater sediment samples. Overall, 91% of 131 surficial marine sediments and 50% of 46 surficial freshwater sediments contained detectable AVS. In 93 of the marine sediments the concentrations of AVS were greater than total SEM (molar sum of copper, cadmium, zinc, nickel, and lead) indicating a low probability of bioavailable metal. In contrast, 91% of the surficial freshwater samples contained greater concentrations of total SEM than AVS. However, pore‒water concentrations of the five metals in the freshwater samples were uniformly low and never exceeded 0.3 toxic units based on an additive toxicity model that utilized final chronic values from EPA water quality criteria documents for the five metals. These predictions of minimal metal bioavailability in the EMAP samples were consistent with a general lack of toxicity in laboratory assays with the sediments and with the fact that they had been collected predominantly from ostensibly uncontaminated sites.
The assessment of contaminated sediments is a difficult task due to the complex nature of the sed... more The assessment of contaminated sediments is a difficult task due to the complex nature of the sediment matrix and the potential for exposure of aquatic organisms to in-place contaminants via several routes. Differential species sensitivity also precludes the completion of a meaningful environmental assessment with only one species. Therefore, a battery of assays approach with the Microtox assay, 48 hr Daphnia magna and Ceriodaphnia dubia tests and a 10-day Chironomous tentans test was used to evaluate the toxicity of sediment pore waters and whole sediments from the Grand Calumet River-Indiana Harbor, Indiana area of concern. All toxicity tests indicated that the test fractions (pore water, whole sediment) from each study site were toxic to the test species. A toxic units (TU) approach was used to compare measured TU from each assay with calculated TU based on chemical analyses of pore waters and whole sediments and the results of reference toxicant tests. Based on the results of these analyses, ammonia, polycyclic aromatic hydrocarbons, metals, petroleum hydrocarbons, and bicarbonate ion appear to be the major contaminants of environmental significance to benthic invertebrates within the study area.
... supernatant. Preparation of multiple ali quants of the elutriate mixture was necessary to obt... more ... supernatant. Preparation of multiple ali quants of the elutriate mixture was necessary to obtain sufficient extract for subsequent testing. ... Ohio. Giesy, JP, Rosiu, CJ, Graney, RL, Newsted, JL, Benda, A., Kreis, Jr., RG, and Horvath, FJ, 1988a. ...
Ecotoxicology and Environmental Safety, Aug 1, 1993
The assessment of contaminated sediments is a difficult task due to the complex nature of the sed... more The assessment of contaminated sediments is a difficult task due to the complex nature of the sediment matrix and the potential for exposure of aquatic organisms to in-place contaminants via several routes. Differential species sensitivity also precludes the completion of a meaningful environmental assessment with only one species. Therefore, a battery of assays approach with the Microtox assay, 48 hr Daphnia magna and Ceriodaphnia dubia tests and a 10-day Chironomous tentans test was used to evaluate the toxicity of sediment pore waters and whole sediments from the Grand Calumet River-Indiana Harbor, Indiana area of concern. All toxicity tests indicated that the test fractions (pore water, whole sediment) from each study site were toxic to the test species. A toxic units (TU) approach was used to compare measured TU from each assay with calculated TU based on chemical analyses of pore waters and whole sediments and the results of reference toxicant tests. Based on the results of these analyses, ammonia, polycyclic aromatic hydrocarbons, metals, petroleum hydrocarbons, and bicarbonate ion appear to be the major contaminants of environmental significance to benthic invertebrates within the study area.
Environmental Toxicology and Chemistry, Nov 1, 1995
... 0730-7268(95)00150-6 Environmental Toxicology TOXICITY AND BIOACCUMULATION OF SEDIMENT-ASSOCI... more ... 0730-7268(95)00150-6 Environmental Toxicology TOXICITY AND BIOACCUMULATION OF SEDIMENT-ASSOCIATED CONTAMINANTS USING FRESHWATER INVERTEBRATES: AREVIEW OF METHODS AND APPLICATIONS ... Nickel 780 NT 12,160 Lead <16 NT 794 ...
Environmental Toxicology and Chemistry, Dec 1, 1996
Surficial sediments collected from Lake Michigan (N = 46) and the Virginian Province of the east ... more Surficial sediments collected from Lake Michigan (N = 46) and the Virginian Province of the east coast of the U.S. (N = 131) by the Environmental Monitoring and Assessment Program (EMAP) of the U.S. Environmental Protection Agency (EPA) were evaluated relative to a proposed approach to sediment quality criteria (SQC) for five metals (copper, cadmium, zinc, nickel, and lead). Concentrations of acid‒volatile sulfide (AVS), simultaneously extracted metals (SEM) from the AVS extraction, total metals, and total organic carbon were measured in the sediments. Interstitial pore‒water concentrations of the five metals also were measured in the freshwater sediment samples. Overall, 91% of 131 surficial marine sediments and 50% of 46 surficial freshwater sediments contained detectable AVS. In 93 of the marine sediments the concentrations of AVS were greater than total SEM (molar sum of copper, cadmium, zinc, nickel, and lead) indicating a low probability of bioavailable metal. In contrast, 91% of the surficial freshwater samples contained greater concentrations of total SEM than AVS. However, pore‒water concentrations of the five metals in the freshwater samples were uniformly low and never exceeded 0.3 toxic units based on an additive toxicity model that utilized final chronic values from EPA water quality criteria documents for the five metals. These predictions of minimal metal bioavailability in the EMAP samples were consistent with a general lack of toxicity in laboratory assays with the sediments and with the fact that they had been collected predominantly from ostensibly uncontaminated sites.
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