The purpose of the Environmental Monitoring and Assessment Program-Surface Waters (EMAP-SW) is to... more The purpose of the Environmental Monitoring and Assessment Program-Surface Waters (EMAP-SW) is to estimate the status and trends in the ecological condition of the nation`s lakes and streams. The three endpoints of concern of EMAP-SW are biological integrity, trophic condition, and fishability. The extent of contaminants in fish tissue is an important component of the condition endpoint of fishability as well as having implications for biological integrity. Composite samples of whole fish from 60 lakes chosen by EMAP`s probability sampling design were analyzed for a suite of target analytes. Whole fish were analyzed due to EMAP-SW`s ecological focus. The extent of EMAP-SW`s chosen target analytes for the fish tissue contaminants indicator for lakes in the northeast region of the United States will be presented. The target analytes of EMAP-SW are 12 common organochlorine pesticides, 13 metals (Al, As, Cd, Cr, Cu, Fe, Pb, Hg, Ni, Se, Ag, Sn, Zn) and 21 polychlorinated biphenyl congeners, including coplanar congeners.
The approach of the Environmental Monitoring and Assessment Program (EMAP) to monitoring of fish ... more The approach of the Environmental Monitoring and Assessment Program (EMAP) to monitoring of fish tissue contaminants is shown to have utility for regional assessment, and for discrimination of regional from local contamination. The survey sampling design employed by EMAP can be used to make regional assessments without conducting a complete resource inventory. The Environmental Monitoring and Assessment Program-Surface Waters conducted a survey of 167 lakes in the northeastern United States during 1992 through 1994 and analyzed whole fish composite samples for contaminants, including Al, As, Cd, Cr, Cu, Fe, Hg, Ni, Pb, Se, and Zn. Using fish tissue contaminant consumption risk levels derived from U.S. Environmental Protection Agency hazard assessment models, methylmercury (MeHg) was determined to be the elemental contaminant of regional concern to fish consumers: 26% of lakes contained fish with MeHg exceeding a human critical value of 0.2 g/g; 54 and 98% of lakes contained fish with MeHg exceeding wildlife critical values for piscivorous mammals (0.1 g/g) and birds (0.02 g/g), respectively. The other elements analyzed appeared to be at safe levels on a regional scale, or only of localized concern with regard to human health.
The unique challenges associated with sampling of macroinvertebrates in flashy urban streams crea... more The unique challenges associated with sampling of macroinvertebrates in flashy urban streams create a methods gap. These streams form isolated pools for much of the year, interspersed with spates that scour and deposit excessive amounts of sediment. Commonly used stream grab sampling methods, such as nets and Hess and Surber fixed-area samplers, work well in wadable streams with perennial flow. Deployed samplers (Hester-Dendy, gravel tray) can be used in waters with or without flow. We evaluated three methods which don't require stream flow: modified Hester-Dendy (MHD), gravel tray, and bucket (a type of cylinder grab sample method), for their potential use in bioassessment of a project involving daylighting of a 180-m culvert on Congress Run, a flashy urban tributary to Mill Creek in Cincinnati, Ohio. Method efficacy was measured using three criteria: usability (level of effort and recoverability of samplers), variability, and community retrieval completeness. The bucket method required the lowest level of effort and had the highest sample recovery. The bucket sampler had the lowest variability for most metrics, including the critical metric of taxa richness, with a coefficient of variation (CV) of 20.9%. The MHD and tray samplers had taxa richness CVs of 42.9% and 53.9%, respectively. The bucket sampler also had the lowest CV (27.4%) for a multi-metric index. The bucket sampler performed best with respect to community retrieval completeness, with higher pooled and average taxa richness. The total number of taxa collected from all the replicate bucket grab samples (42) was greater than that collected by the HD and tray samplers combined (27). Multivariate analyses showed significant grouping with respect to methods and location. This study supports the bucket grab sampler method as a candidate for sampling of flashy urban streams.
Industrial chemical contamination within coastal regions of the Great Lakes can pose serious risk... more Industrial chemical contamination within coastal regions of the Great Lakes can pose serious risks to wetland habitat and offshore fisheries, often resulting in fish consumption advisories that directly affect human and wildlife health. Mercury (Hg) is a contaminant of concern in many of these highly urbanized and industrialized coastal regions, one of which is the Saint Louis River estuary (SLRE), the second largest tributary to Lake Superior. The SLRE has legacy Hg contamination that drives high Hg concentrations within sediments, but it is unclear whether legacy-derived Hg actively cycles within the food web. To understand the relative contributions of legacy versus contemporary Hg sources in coastal zones, Hg, carbon, and nitrogen stable isotope ratios were measured in sediments and food webs of SLRE and the Bad River, an estuarine reference site. Hg stable isotope values revealed that legacy contamination of Hg was widespread and heterogeneously distributed in sediments of SLRE, even in areas lacking industrial Hg sources. Similar isotope values were found in benthic invertebrates, riparian spiders, and prey fish from SLRE, confirming legacy Hg reaches the SLRE food web. Direct comparison of prey fish from SLRE and the Bad River confirmed that Hg isotope differences between the sites were not attributable to fractionation associated with rapid Hg bioaccumulation at estuarine mouths, but due to the presence of industrial Hg within SLRE. The Hg stable isotope values of game fish in both estuaries were dependent on fish migration and diet within the estuaries and extending into Lake Superior. These results indicate that Hg from legacy contamination is actively cycling within the SLRE food web and, through migration, this Hg also extends into Lake Superior via game fish. Understanding sources and the movement of Hg within the estuarine food web better informs restoration strategies for other impaired Great Lakes coastal zones.
This presentation will explore associations between mercury in fish tissue and other measures of ... more This presentation will explore associations between mercury in fish tissue and other measures of lake quality as one method of diagnosing the source or cause of high fish tissue mercury levels. The EMAP-Surface Waters multi-indicator approach helps to make such a diagnosis possible. Correlations between fish tissue mercury data from the 1992 and 1993 EMAP-SW Northeast Pilot studies and corresponding site data from other indicators were found that support specific sources and causes of high mercury levels in fish. Metrics from the stressor indicator (which describe characteristics likely to impact an ecosystem, such as land use) point to a contribution of mercury from atmospheric sources being more important than that from local watershed sources. Lakes with high levels of Hg in fish tissue have less associated local human disturbance: lower population and point source densities and lower percent of total human-disturbed land use in lake watersheds. A positive correlation between runoff and fish mercury levels is also seen, showing the importance of precipitation as at least a contributing factor. Metrics from the water chemistry indicator support correlations seen in other studies between high mercury fish tissue levels and low pH and low acid neutralizing capacity (ANC). Lakes with high mercurymore » fish tissue levels ({>=} 0.2 ppm) were found to have statistically lower water pH and ANC. A correlation was also seen between chemical measures of oligotrophy (lower total-p, total-N, and chlorophyll) and high fish mercury levels, supporting a tissue dilution theory. These as well as other associations are explored.« less
The purpose of the Environmental Monitoring and Assessment Program-Surface Waters (EMAP-SW) is to... more The purpose of the Environmental Monitoring and Assessment Program-Surface Waters (EMAP-SW) is to estimate the status and trends in the ecological condition of the nation`s lakes and streams. The three endpoints of concern of EMAP-SW are biological integrity, trophic condition, and fishability. The extent of contaminants in fish tissue is an important component of the condition endpoint of fishability as well as having implications for biological integrity. Composite samples of whole fish from 60 lakes chosen by EMAP`s probability sampling design were analyzed for a suite of target analytes. Whole fish were analyzed due to EMAP-SW`s ecological focus. The extent of EMAP-SW`s chosen target analytes for the fish tissue contaminants indicator for lakes in the northeast region of the United States will be presented. The target analytes of EMAP-SW are 12 common organochlorine pesticides, 13 metals (Al, As, Cd, Cr, Cu, Fe, Pb, Hg, Ni, Se, Ag, Sn, Zn) and 21 polychlorinated biphenyl congeners, including coplanar congeners.
The use of the 14-d earthworm toxicity test to aid in the evaluation of the ecological impact of ... more The use of the 14-d earthworm toxicity test to aid in the evaluation of the ecological impact of contaminated soils is becoming increasingly widespread. However, the method is in need of further standardization. As part of this continuing process, the choice of reference toxicants was evaluated. Reference toxicants were rated in relation to the following criteria: (a) reproducibility, (b) low human health hazard, (c) feasibility of measurement, and (d) chemical stability. Potassium chloride (KCl) and ammonium chloride (NH,CI) were evaluated as possible alternatives to the one currently in common use, 2-chloroacetamide. Potassium chloride rated the best for the combination of the four criteria, followed by NH4C1 and 2-chloroacetamide. Coefficients of variation (C.V.s) from control charts of six definitive tests were used to measure reproducibility. The best reproducibility (lowest C.V.) was shown by KC1, followed by NH4C1 and 2-chloroacetamide. Toxicants ranked KCl < NH4C1 << 2-chloroacetamide in terms of health hazard; and KC1 = NH,Cl> 2-chloroacetamide in terms of measurement feasibility. Both 2-chloroacetamide and NH,Cl changed in concentration during testing. Evidence is also presented that 2-chloroacetamide degrades rapidly during testing, and that, as dead worms decay, ammonification may be adding another toxicant, ammonia, to tests.
Environmental Monitoring and Assessment, Nov 30, 2000
Selection of fish species for sampling to assess extent and potential effects of fish tissue cont... more Selection of fish species for sampling to assess extent and potential effects of fish tissue contaminants is a critical consideration in the design of regional probability-design surveys. The ideal species would be ubiquitous, bioaccumulate toxic chemicals, and be prey of consumers of concern (piscivorous wildlife, humans). In first to third order streams, small short-lived forage fish (minnows (F. Cyprinidae), darters (F. Percidae), and sculpins (F. Cottidae), are more frequently found and therefore likely to be prey to more species of wildlife than those of sportfish whose adults grow to a large size (suckers (F. Catostomidae), trout (F. Salmonidae), bass, and sunfish (F. Centrarchidae), and carp). Targeting smaller forage fish should also produce a larger number of individuals per sample on average than may be achieved with the larger species. An analysis of fish collected in 1993 and 1994 as part of the Mid-Atlantic Highlands Assessment (MAHA) showed that, as expected, forage fish were more ubiquitous than sportfish species. Analysis also revealed that, on a regional basis, forage fish bioaccumulated comparable levels to sportfish, of some widely occurring contaminants such as DDT, MeHg, and PCBs. Results indicated that smaller forage fish can be used as indicator species for a regional assessment for most contaminants (Zn being the one clear exception), that was not significantly different from one based on the larger species. Forage fish may therefore be an excellent choice as indicator species for regional streams ecological risk assessment studies.
Thesis (M.S.)--University of Cincinnati, 1991. Includes bibliographical references (leaves 154-17... more Thesis (M.S.)--University of Cincinnati, 1991. Includes bibliographical references (leaves 154-175). Includes abstract.
Selection of fish species for sampling to assess extent and potential effects of fish tissue cont... more Selection of fish species for sampling to assess extent and potential effects of fish tissue contaminants is a critical consideration in the design of regional probability-design surveys. The ideal species would be ubiquitous, bioaccumulate toxic chemicals, and be prey of consumers of concern (piscivorous wildlife, humans). In first to third order streams, small short-lived forage fish (minnows (F. Cyprinidae), darters (F. Percidae), and sculpins (F. Cottidae), are more frequently found and therefore likely to be prey to more species of wildlife than those of sportfish whose adults grow to a large size (suckers (F. Catostomidae), trout (F. Salmonidae), bass, and sunfish (F. Centrarchidae), and carp). Targeting smaller forage fish should also produce a larger number of individuals per sample on average than may be achieved with the larger species. An analysis of fish collected in 1993 and 1994 as part of the Mid-Atlantic Highlands Assessment (MAHA) showed that, as expected, forage fish were more ubiquitous than sportfish species. Analysis also revealed that, on a regional basis, forage fish bioaccumulated comparable levels to sportfish, of some widely occurring contaminants such as DDT, MeHg, and PCBs. Results indicated that smaller forage fish can be used as indicator species for a regional assessment for most contaminants (Zn being the one clear exception), that was not significantly different from one based on the larger species. Forage fish may therefore be an excellent choice as indicator species for regional streams ecological risk assessment studies.
We determined effects of acidification on sediment aerobic heterotrophic exo-amyIase and exo-prot... more We determined effects of acidification on sediment aerobic heterotrophic exo-amyIase and exo-protease producing microbial populations in addition to effects on the total microbial population. Acidification of microcosms to sediment pHs of 6,5,4, and 3 followed by plate counts showed that numbers of total aerobic heterotrophic microbes, as well as numbers exo-amylase producers and exo-protease producers, decreased at pH 3. It appears that pH 3 may represent a critical level of damage. Numbers of total aerobic heterotrophs also decreased at pH 4. Numbers of all groups increased at pH 6. An accompanying change in species composition was observed with acidification, in which a type of microbe with little production of exo-amylase or exo-protease became dominant in the microbial community as pH decreased. Analysis of three metals (Al, Pb, Cu) indicated an increased mobilization of metals from the sediments at low pHs.
... ROGER B. YEARDLEY, JR.,*† JAMES M. LAZORCHAK‡ and LAURA C. GAST† †DynCorp, c/o US Environment... more ... ROGER B. YEARDLEY, JR.,*† JAMES M. LAZORCHAK‡ and LAURA C. GAST† †DynCorp, c/o US Environmental Protection Agency, 3411 Church Street ... The AS dry ingredients were, by weight, 70% of 70 grade washed silica sand, 20% kaolin clay, and 10% Canadian peat ...
The use of the 14-d earthworm toxicity test to aid in the evaluation of the ecological impact of ... more The use of the 14-d earthworm toxicity test to aid in the evaluation of the ecological impact of contaminated soils is becoming increasingly widespread. However, the method is in need of further standardization. As part of this continuing process, the choice of reference toxicants was evaluated. Reference toxicants were rated in relation to the following criteria: (a) reproducibility, (b) low human health hazard, (c) feasibility of measurement, and (d) chemical stability. Potassium chloride (KCl) and ammonium chloride (NH,CI) were evaluated as possible alternatives to the one currently in common use, 2-chloroacetamide. Potassium chloride rated the best for the combination of the four criteria, followed by NH4C1 and 2-chloroacetamide. Coefficients of variation (C.V.s) from control charts of six definitive tests were used to measure reproducibility. The best reproducibility (lowest C.V.) was shown by KC1, followed by NH4C1 and 2-chloroacetamide. Toxicants ranked KCl < NH4C1 << 2-chloroacetamide in terms of health hazard; and KC1 = NH,Cl> 2-chloroacetamide in terms of measurement feasibility. Both 2-chloroacetamide and NH,Cl changed in concentration during testing. Evidence is also presented that 2-chloroacetamide degrades rapidly during testing, and that, as dead worms decay, ammonification may be adding another toxicant, ammonia, to tests.
... A need to know the condition of ecological resources at regional and national scales prompted... more ... A need to know the condition of ecological resources at regional and national scales prompted ... population statistics such as means, medians, variances, or proportions above or below some critical value. ... in whole fish were measured as a part of an EMAP-SW regional survey of ...
Selection of fish species for sampling to assess extent and potential effects of fish tissue cont... more Selection of fish species for sampling to assess extent and potential effects of fish tissue contaminants is a critical consideration in the design of regional probability-design surveys. The ideal species would be ubiquitous, bioaccumulate toxic chemicals, and be prey of consumers of concern (piscivorous wildlife, humans). In first to third order streams, small short-lived forage fish (minnows (F. Cyprinidae), darters (F. Percidae), and sculpins (F. Cottidae), are more frequently found and therefore likely to be prey to more species of wildlife than those of sportfish whose adults grow to a large size (suckers (F. Catostomidae), trout (F. Salmonidae), bass, and sunfish (F. Centrarchidae), and carp). Targeting smaller forage fish should also produce a larger number of individuals per sample on average than may be achieved with the larger species. An analysis of fish collected in 1993 and 1994 as part of the Mid-Atlantic Highlands Assessment (MAHA) showed that, as expected, forage fish were more ubiquitous than sportfish species. Analysis also revealed that, on a regional basis, forage fish bioaccumulated comparable levels to sportfish, of some widely occurring contaminants such as DDT, MeHg, and PCBs. Results indicated that smaller forage fish can be used as indicator species for a regional assessment for most contaminants (Zn being the one clear exception), that was not significantly different from one based on the larger species. Forage fish may therefore be an excellent choice as indicator species for regional streams ecological risk assessment studies.
The purpose of the Environmental Monitoring and Assessment Program-Surface Waters (EMAP-SW) is to... more The purpose of the Environmental Monitoring and Assessment Program-Surface Waters (EMAP-SW) is to estimate the status and trends in the ecological condition of the nation`s lakes and streams. The three endpoints of concern of EMAP-SW are biological integrity, trophic condition, and fishability. The extent of contaminants in fish tissue is an important component of the condition endpoint of fishability as well as having implications for biological integrity. Composite samples of whole fish from 60 lakes chosen by EMAP`s probability sampling design were analyzed for a suite of target analytes. Whole fish were analyzed due to EMAP-SW`s ecological focus. The extent of EMAP-SW`s chosen target analytes for the fish tissue contaminants indicator for lakes in the northeast region of the United States will be presented. The target analytes of EMAP-SW are 12 common organochlorine pesticides, 13 metals (Al, As, Cd, Cr, Cu, Fe, Pb, Hg, Ni, Se, Ag, Sn, Zn) and 21 polychlorinated biphenyl congeners, including coplanar congeners.
The approach of the Environmental Monitoring and Assessment Program (EMAP) to monitoring of fish ... more The approach of the Environmental Monitoring and Assessment Program (EMAP) to monitoring of fish tissue contaminants is shown to have utility for regional assessment, and for discrimination of regional from local contamination. The survey sampling design employed by EMAP can be used to make regional assessments without conducting a complete resource inventory. The Environmental Monitoring and Assessment Program-Surface Waters conducted a survey of 167 lakes in the northeastern United States during 1992 through 1994 and analyzed whole fish composite samples for contaminants, including Al, As, Cd, Cr, Cu, Fe, Hg, Ni, Pb, Se, and Zn. Using fish tissue contaminant consumption risk levels derived from U.S. Environmental Protection Agency hazard assessment models, methylmercury (MeHg) was determined to be the elemental contaminant of regional concern to fish consumers: 26% of lakes contained fish with MeHg exceeding a human critical value of 0.2 g/g; 54 and 98% of lakes contained fish with MeHg exceeding wildlife critical values for piscivorous mammals (0.1 g/g) and birds (0.02 g/g), respectively. The other elements analyzed appeared to be at safe levels on a regional scale, or only of localized concern with regard to human health.
The unique challenges associated with sampling of macroinvertebrates in flashy urban streams crea... more The unique challenges associated with sampling of macroinvertebrates in flashy urban streams create a methods gap. These streams form isolated pools for much of the year, interspersed with spates that scour and deposit excessive amounts of sediment. Commonly used stream grab sampling methods, such as nets and Hess and Surber fixed-area samplers, work well in wadable streams with perennial flow. Deployed samplers (Hester-Dendy, gravel tray) can be used in waters with or without flow. We evaluated three methods which don't require stream flow: modified Hester-Dendy (MHD), gravel tray, and bucket (a type of cylinder grab sample method), for their potential use in bioassessment of a project involving daylighting of a 180-m culvert on Congress Run, a flashy urban tributary to Mill Creek in Cincinnati, Ohio. Method efficacy was measured using three criteria: usability (level of effort and recoverability of samplers), variability, and community retrieval completeness. The bucket method required the lowest level of effort and had the highest sample recovery. The bucket sampler had the lowest variability for most metrics, including the critical metric of taxa richness, with a coefficient of variation (CV) of 20.9%. The MHD and tray samplers had taxa richness CVs of 42.9% and 53.9%, respectively. The bucket sampler also had the lowest CV (27.4%) for a multi-metric index. The bucket sampler performed best with respect to community retrieval completeness, with higher pooled and average taxa richness. The total number of taxa collected from all the replicate bucket grab samples (42) was greater than that collected by the HD and tray samplers combined (27). Multivariate analyses showed significant grouping with respect to methods and location. This study supports the bucket grab sampler method as a candidate for sampling of flashy urban streams.
Industrial chemical contamination within coastal regions of the Great Lakes can pose serious risk... more Industrial chemical contamination within coastal regions of the Great Lakes can pose serious risks to wetland habitat and offshore fisheries, often resulting in fish consumption advisories that directly affect human and wildlife health. Mercury (Hg) is a contaminant of concern in many of these highly urbanized and industrialized coastal regions, one of which is the Saint Louis River estuary (SLRE), the second largest tributary to Lake Superior. The SLRE has legacy Hg contamination that drives high Hg concentrations within sediments, but it is unclear whether legacy-derived Hg actively cycles within the food web. To understand the relative contributions of legacy versus contemporary Hg sources in coastal zones, Hg, carbon, and nitrogen stable isotope ratios were measured in sediments and food webs of SLRE and the Bad River, an estuarine reference site. Hg stable isotope values revealed that legacy contamination of Hg was widespread and heterogeneously distributed in sediments of SLRE, even in areas lacking industrial Hg sources. Similar isotope values were found in benthic invertebrates, riparian spiders, and prey fish from SLRE, confirming legacy Hg reaches the SLRE food web. Direct comparison of prey fish from SLRE and the Bad River confirmed that Hg isotope differences between the sites were not attributable to fractionation associated with rapid Hg bioaccumulation at estuarine mouths, but due to the presence of industrial Hg within SLRE. The Hg stable isotope values of game fish in both estuaries were dependent on fish migration and diet within the estuaries and extending into Lake Superior. These results indicate that Hg from legacy contamination is actively cycling within the SLRE food web and, through migration, this Hg also extends into Lake Superior via game fish. Understanding sources and the movement of Hg within the estuarine food web better informs restoration strategies for other impaired Great Lakes coastal zones.
This presentation will explore associations between mercury in fish tissue and other measures of ... more This presentation will explore associations between mercury in fish tissue and other measures of lake quality as one method of diagnosing the source or cause of high fish tissue mercury levels. The EMAP-Surface Waters multi-indicator approach helps to make such a diagnosis possible. Correlations between fish tissue mercury data from the 1992 and 1993 EMAP-SW Northeast Pilot studies and corresponding site data from other indicators were found that support specific sources and causes of high mercury levels in fish. Metrics from the stressor indicator (which describe characteristics likely to impact an ecosystem, such as land use) point to a contribution of mercury from atmospheric sources being more important than that from local watershed sources. Lakes with high levels of Hg in fish tissue have less associated local human disturbance: lower population and point source densities and lower percent of total human-disturbed land use in lake watersheds. A positive correlation between runoff and fish mercury levels is also seen, showing the importance of precipitation as at least a contributing factor. Metrics from the water chemistry indicator support correlations seen in other studies between high mercury fish tissue levels and low pH and low acid neutralizing capacity (ANC). Lakes with high mercurymore » fish tissue levels ({>=} 0.2 ppm) were found to have statistically lower water pH and ANC. A correlation was also seen between chemical measures of oligotrophy (lower total-p, total-N, and chlorophyll) and high fish mercury levels, supporting a tissue dilution theory. These as well as other associations are explored.« less
The purpose of the Environmental Monitoring and Assessment Program-Surface Waters (EMAP-SW) is to... more The purpose of the Environmental Monitoring and Assessment Program-Surface Waters (EMAP-SW) is to estimate the status and trends in the ecological condition of the nation`s lakes and streams. The three endpoints of concern of EMAP-SW are biological integrity, trophic condition, and fishability. The extent of contaminants in fish tissue is an important component of the condition endpoint of fishability as well as having implications for biological integrity. Composite samples of whole fish from 60 lakes chosen by EMAP`s probability sampling design were analyzed for a suite of target analytes. Whole fish were analyzed due to EMAP-SW`s ecological focus. The extent of EMAP-SW`s chosen target analytes for the fish tissue contaminants indicator for lakes in the northeast region of the United States will be presented. The target analytes of EMAP-SW are 12 common organochlorine pesticides, 13 metals (Al, As, Cd, Cr, Cu, Fe, Pb, Hg, Ni, Se, Ag, Sn, Zn) and 21 polychlorinated biphenyl congeners, including coplanar congeners.
The use of the 14-d earthworm toxicity test to aid in the evaluation of the ecological impact of ... more The use of the 14-d earthworm toxicity test to aid in the evaluation of the ecological impact of contaminated soils is becoming increasingly widespread. However, the method is in need of further standardization. As part of this continuing process, the choice of reference toxicants was evaluated. Reference toxicants were rated in relation to the following criteria: (a) reproducibility, (b) low human health hazard, (c) feasibility of measurement, and (d) chemical stability. Potassium chloride (KCl) and ammonium chloride (NH,CI) were evaluated as possible alternatives to the one currently in common use, 2-chloroacetamide. Potassium chloride rated the best for the combination of the four criteria, followed by NH4C1 and 2-chloroacetamide. Coefficients of variation (C.V.s) from control charts of six definitive tests were used to measure reproducibility. The best reproducibility (lowest C.V.) was shown by KC1, followed by NH4C1 and 2-chloroacetamide. Toxicants ranked KCl < NH4C1 << 2-chloroacetamide in terms of health hazard; and KC1 = NH,Cl> 2-chloroacetamide in terms of measurement feasibility. Both 2-chloroacetamide and NH,Cl changed in concentration during testing. Evidence is also presented that 2-chloroacetamide degrades rapidly during testing, and that, as dead worms decay, ammonification may be adding another toxicant, ammonia, to tests.
Environmental Monitoring and Assessment, Nov 30, 2000
Selection of fish species for sampling to assess extent and potential effects of fish tissue cont... more Selection of fish species for sampling to assess extent and potential effects of fish tissue contaminants is a critical consideration in the design of regional probability-design surveys. The ideal species would be ubiquitous, bioaccumulate toxic chemicals, and be prey of consumers of concern (piscivorous wildlife, humans). In first to third order streams, small short-lived forage fish (minnows (F. Cyprinidae), darters (F. Percidae), and sculpins (F. Cottidae), are more frequently found and therefore likely to be prey to more species of wildlife than those of sportfish whose adults grow to a large size (suckers (F. Catostomidae), trout (F. Salmonidae), bass, and sunfish (F. Centrarchidae), and carp). Targeting smaller forage fish should also produce a larger number of individuals per sample on average than may be achieved with the larger species. An analysis of fish collected in 1993 and 1994 as part of the Mid-Atlantic Highlands Assessment (MAHA) showed that, as expected, forage fish were more ubiquitous than sportfish species. Analysis also revealed that, on a regional basis, forage fish bioaccumulated comparable levels to sportfish, of some widely occurring contaminants such as DDT, MeHg, and PCBs. Results indicated that smaller forage fish can be used as indicator species for a regional assessment for most contaminants (Zn being the one clear exception), that was not significantly different from one based on the larger species. Forage fish may therefore be an excellent choice as indicator species for regional streams ecological risk assessment studies.
Thesis (M.S.)--University of Cincinnati, 1991. Includes bibliographical references (leaves 154-17... more Thesis (M.S.)--University of Cincinnati, 1991. Includes bibliographical references (leaves 154-175). Includes abstract.
Selection of fish species for sampling to assess extent and potential effects of fish tissue cont... more Selection of fish species for sampling to assess extent and potential effects of fish tissue contaminants is a critical consideration in the design of regional probability-design surveys. The ideal species would be ubiquitous, bioaccumulate toxic chemicals, and be prey of consumers of concern (piscivorous wildlife, humans). In first to third order streams, small short-lived forage fish (minnows (F. Cyprinidae), darters (F. Percidae), and sculpins (F. Cottidae), are more frequently found and therefore likely to be prey to more species of wildlife than those of sportfish whose adults grow to a large size (suckers (F. Catostomidae), trout (F. Salmonidae), bass, and sunfish (F. Centrarchidae), and carp). Targeting smaller forage fish should also produce a larger number of individuals per sample on average than may be achieved with the larger species. An analysis of fish collected in 1993 and 1994 as part of the Mid-Atlantic Highlands Assessment (MAHA) showed that, as expected, forage fish were more ubiquitous than sportfish species. Analysis also revealed that, on a regional basis, forage fish bioaccumulated comparable levels to sportfish, of some widely occurring contaminants such as DDT, MeHg, and PCBs. Results indicated that smaller forage fish can be used as indicator species for a regional assessment for most contaminants (Zn being the one clear exception), that was not significantly different from one based on the larger species. Forage fish may therefore be an excellent choice as indicator species for regional streams ecological risk assessment studies.
We determined effects of acidification on sediment aerobic heterotrophic exo-amyIase and exo-prot... more We determined effects of acidification on sediment aerobic heterotrophic exo-amyIase and exo-protease producing microbial populations in addition to effects on the total microbial population. Acidification of microcosms to sediment pHs of 6,5,4, and 3 followed by plate counts showed that numbers of total aerobic heterotrophic microbes, as well as numbers exo-amylase producers and exo-protease producers, decreased at pH 3. It appears that pH 3 may represent a critical level of damage. Numbers of total aerobic heterotrophs also decreased at pH 4. Numbers of all groups increased at pH 6. An accompanying change in species composition was observed with acidification, in which a type of microbe with little production of exo-amylase or exo-protease became dominant in the microbial community as pH decreased. Analysis of three metals (Al, Pb, Cu) indicated an increased mobilization of metals from the sediments at low pHs.
... ROGER B. YEARDLEY, JR.,*† JAMES M. LAZORCHAK‡ and LAURA C. GAST† †DynCorp, c/o US Environment... more ... ROGER B. YEARDLEY, JR.,*† JAMES M. LAZORCHAK‡ and LAURA C. GAST† †DynCorp, c/o US Environmental Protection Agency, 3411 Church Street ... The AS dry ingredients were, by weight, 70% of 70 grade washed silica sand, 20% kaolin clay, and 10% Canadian peat ...
The use of the 14-d earthworm toxicity test to aid in the evaluation of the ecological impact of ... more The use of the 14-d earthworm toxicity test to aid in the evaluation of the ecological impact of contaminated soils is becoming increasingly widespread. However, the method is in need of further standardization. As part of this continuing process, the choice of reference toxicants was evaluated. Reference toxicants were rated in relation to the following criteria: (a) reproducibility, (b) low human health hazard, (c) feasibility of measurement, and (d) chemical stability. Potassium chloride (KCl) and ammonium chloride (NH,CI) were evaluated as possible alternatives to the one currently in common use, 2-chloroacetamide. Potassium chloride rated the best for the combination of the four criteria, followed by NH4C1 and 2-chloroacetamide. Coefficients of variation (C.V.s) from control charts of six definitive tests were used to measure reproducibility. The best reproducibility (lowest C.V.) was shown by KC1, followed by NH4C1 and 2-chloroacetamide. Toxicants ranked KCl < NH4C1 << 2-chloroacetamide in terms of health hazard; and KC1 = NH,Cl> 2-chloroacetamide in terms of measurement feasibility. Both 2-chloroacetamide and NH,Cl changed in concentration during testing. Evidence is also presented that 2-chloroacetamide degrades rapidly during testing, and that, as dead worms decay, ammonification may be adding another toxicant, ammonia, to tests.
... A need to know the condition of ecological resources at regional and national scales prompted... more ... A need to know the condition of ecological resources at regional and national scales prompted ... population statistics such as means, medians, variances, or proportions above or below some critical value. ... in whole fish were measured as a part of an EMAP-SW regional survey of ...
Selection of fish species for sampling to assess extent and potential effects of fish tissue cont... more Selection of fish species for sampling to assess extent and potential effects of fish tissue contaminants is a critical consideration in the design of regional probability-design surveys. The ideal species would be ubiquitous, bioaccumulate toxic chemicals, and be prey of consumers of concern (piscivorous wildlife, humans). In first to third order streams, small short-lived forage fish (minnows (F. Cyprinidae), darters (F. Percidae), and sculpins (F. Cottidae), are more frequently found and therefore likely to be prey to more species of wildlife than those of sportfish whose adults grow to a large size (suckers (F. Catostomidae), trout (F. Salmonidae), bass, and sunfish (F. Centrarchidae), and carp). Targeting smaller forage fish should also produce a larger number of individuals per sample on average than may be achieved with the larger species. An analysis of fish collected in 1993 and 1994 as part of the Mid-Atlantic Highlands Assessment (MAHA) showed that, as expected, forage fish were more ubiquitous than sportfish species. Analysis also revealed that, on a regional basis, forage fish bioaccumulated comparable levels to sportfish, of some widely occurring contaminants such as DDT, MeHg, and PCBs. Results indicated that smaller forage fish can be used as indicator species for a regional assessment for most contaminants (Zn being the one clear exception), that was not significantly different from one based on the larger species. Forage fish may therefore be an excellent choice as indicator species for regional streams ecological risk assessment studies.
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