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Donald D Macdonald - One of the best experts on this subject based on the ideXlab platform.
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calculation and uses of mean Sediment Quality guideline quotients a critical review
Environmental Science & Technology, 2006Co-Authors: Edward R Long, Christopher G Ingersoll, Donald D MacdonaldAbstract:Fine-grained Sediments contaminated with complex mixtures of organic and inorganic chemical contaminants can be toxic in laboratory tests and/or cause adverse impacts to resident benthic communities. Effects-based, Sediment Quality guidelines (SQGs) have been developed over the past 20 years to aid in the interpretation of the relationships between chemical contamination and measures of adverse biological effects. Mean Sediment Quality guideline quotients (mSQGQ) can be calculated by dividing the concentrations of chemicals in Sediments by their respective SQGs and calculating the mean of the quotients for the individual chemicals. The resulting index provides a method of accounting for both the presence and the concentrations of multiple chemicals in Sediments relative to their effects-based guidelines. Analyses of considerable amounts of data demonstrated that both the incidence and magnitude of toxicity in laboratory tests and the incidence of impairment to benthic communities increases incrementally with increasing mSQGQs. Such concentration/response relationships provide a basis for estimating toxicological risks to Sediment-dwelling organisms associated with exposure to contaminated Sediments with a known degree of accuracy. This Sediment Quality assessment tool has been used in numerous surveys and studies since 1994. Nevertheless, mean SQGQs have some important limitations and underlying assumptions that should be understood by Sediment Quality assessors. This paper provides an overview of the derivation methods and some of the principal advantages, assumptions, and limitations in the use of this Sediment assessmenttool. Ideally, mean SQGQs should be included with other measures including results of toxicity tests and benthic community surveys to provide a weight of evidence when assessing the relative Quality of contaminated Sediments.
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applications of numerical Sediment Quality targets for assessing Sediment Quality conditions in a us great lakes area of concern
Environmental Management, 2003Co-Authors: Judy L. Crane, Donald D MacdonaldAbstract:Contaminated Sediments are receiving increasing recognition around the world, leading to the development of various Sediment Quality indicators for assessment, management, remediation, and restoration efforts. Sediment chemistry represents an important indicator of ecosystem health, with the concentrations of contaminants of potential concern (COPCs) providing measurable characteristics for this indicator. The St. Louis River Area of Concern (AOC), located in the western arm of Lake Superior, provides a case study for how numerical Sediment Quality targets (SQTs) for the protection of Sediment-dwelling organisms can be used to support the interpretation of Sediment chemistry data. Two types of SQTs have been established for 33 COPCs in the St. Louis River AOC. The Level I SQTs define the concentrations of contaminants below which Sediment toxicity is unlikely to occur, whereas the Level II SQTs represent the concentrations that, if exceeded, are likely to be associated with Sediment toxicity. The numerical SQTs provide useful tools for making Sediment management decisions, especially when considered as part of a weight-of-evidence approach that includes other Sediment Quality indicators, such as Sediment contaminant chemistry and geochemical characteristics, Sediment toxicity, and benthic macroinvertebrate community structure. The recommended applications of using the numerical SQTs in the St. Louis River AOC include: designing monitoring programs, interpreting Sediment chemistry data, conducting ecological risk assessments, and developing site-specific Sediment Quality remediation targets for small, simple sites where adverse biological effects are likely. Other jurisdictions may benefit from using these recommended applications in their own Sediment Quality programs.
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evaluation of numerical Sediment Quality targets for the st louis river area of concern
Archives of Environmental Contamination and Toxicology, 2002Co-Authors: Judy L. Crane, Donald D Macdonald, Christopher G Ingersoll, T A Berger, D E Smorong, R A Lindskoog, Corinne G Severn, L J FieldAbstract:Numerical Sediment Quality targets (SQTs) for the protection of Sediment-dwelling organisms have been established for the St. Louis River Area of Concern (AOC), 1 of 42 current AOCs in the Great Lakes basin. The two types of SQTs were established primarily from consensus-based Sediment Quality guidelines. Level I SQTs are intended to identify contaminant concentrations below which harmful effects on Sediment-dwelling organisms are unlikely to be observed. Level II SQTs are intended to identify contaminant concentrations above which harmful effects on Sediment-dwelling organisms are likely to be observed. The predictive ability of the numerical SQTs was evaluated using the matching Sediment chemistry and toxicity data set for the St. Louis River AOC. This evaluation involved determination of the incidence of toxicity to amphipods (Hyalella azteca) and midges (Chironomus tentans) within five ranges of Level II SQT quotients (i.e., mean probable effect concentration quotients [PEC-Qs]). The incidence of toxicity was determined based on the results of 10-day toxicity tests with amphipods (endpoints: survival and growth) and 10-day toxicity tests with midges (endpoints: survival and growth). For both toxicity tests, the incidence of toxicity increased as the mean PEC-Q ranges increased. The incidence of toxicity observed in these tests was also compared to that for other geographic areas in the Great Lakes region and in North America for 10- to 14-day amphipod (H. azteca) and 10- to 14-day midge (C. tentans or C. riparius) toxicity tests. In general, the predictive ability of the mean PEC-Qs was similar across geographic areas. The results of these predictive ability evaluations indicate that collectively the mean PEC-Qs provide a reliable basis for classifying Sediments as toxic or not toxic in the St. Louis River AOC, in the larger geographic areas of the Great Lakes, and elsewhere in North America.
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classifying probabilities of acute toxicity in marine Sediments with empirically derived Sediment Quality guidelines
Environmental Toxicology and Chemistry, 2000Co-Authors: Edward R Long, Donald D Macdonald, Corinne G Severn, Carolyn B HongAbstract:Matching, marine Sediment chemistry, and toxicity data (n = 1,513), compiled from three studies conducted in the United States, were analyzed to determine both the frequency of acute toxicity to amphipods and average percentage survival in laboratory bioassays within ranges in toxicant concentrations. We determined that the probability of observing acute toxicity was relatively low (<10%) and that average control-adjusted survival equaled or exceeded 92% in samples in which Sediment Quality guidelines were not exceeded. Both the incidence of toxicity increased and average survival decreased as chemical concentrations increased relative to the guidelines. In Sediments with highest contaminant concentrations, 73 to 83% of the samples were highly toxic, and average control-adjusted amphipod survival was 37 to 46%. Results of this study confirm that the relationships between Sediment chemical concentrations and toxicity reported in a previous study were robust. Further, they indicate that numerical guidelines for saltwater Sediments can be used to estimate the probability of observing toxic effects in acute amphipod tests.
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development and evaluation of consensus based Sediment Quality guidelines for freshwater ecosystems
Archives of Environmental Contamination and Toxicology, 2000Co-Authors: Donald D Macdonald, Christopher G Ingersoll, T A BergerAbstract:Numerical Sediment Quality guidelines (SQGs) for freshwater ecosystems have previously been developed using a variety of approaches. Each approach has certain advantages and limitations which influence their application in the Sediment Quality assessment process. In an effort to focus on the agreement among these various published SQGs, consensus-based SQGs were developed for 28 chemicals of concern in freshwater Sediments (i.e., metals, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and pesticides). For each contaminant of concern, two SQGs were developed from the published SQGs, including a threshold effect concentration (TEC) and a probable effect concentration (PEC). The resultant SQGs for each chemical were evaluated for reliability using matching Sediment chemistry and toxicity data from field studies conducted throughout the United States. The results of this evaluation indicated that most of the TECs (i.e., 21 of 28) provide an accurate basis for predicting the absence of Sediment toxicity. Similarly, most of the PECs (i.e., 16 of 28) provide an accurate basis for predicting Sediment toxicity. Mean PEC quotients were calculated to evaluate the combined effects of multiple contaminants in Sediment. Results of the evaluation indicate that the incidence of toxicity is highly correlated to the mean PEC quotient (R(2) = 0.98 for 347 samples). It was concluded that the consensus-based SQGs provide a reliable basis for assessing Sediment Quality conditions in freshwater ecosystems.
Angel T Delvalls - One of the best experts on this subject based on the ideXlab platform.
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validation of arenicola marina in field toxicity bioassays using benthic cages biomarkers as tools for assessing Sediment Quality
Marine Pollution Bulletin, 2011Co-Authors: Julia Ramosgomez, Laura M Martindiaz, Marta Martins, Joana Raimundo, Carlos Vale, Angel T DelvallsAbstract:Sediment toxicity assessments using caged organisms present advantages over using laboratory and native community studies. The use of caged Arenicola marina in Sediment toxicity assessments was evaluated. Lugworms were exposed in situ to Sediments from coastal and port areas in Spain for seven days, and the activities of the biotransformation enzymes ethoxyresorufin O-deethylase, dibenzylfluorescein dealkylase and glutathione S-transferase, the activities of the antioxidant enzymes glutathione reductase and glutathione peroxidase and lipid peroxidation were then analyzed as biomarkers. Biomarker results and Sediment physicochemical data were integrated. Cadiz Bay (SW Spain) Sediments presented metal contamination that was not linked to a biochemical response. In LPGC Port (SW Spain), Pb contamination exhibited a moderate toxic potential, while PAHs, and presumably pharmaceuticals, provoked biochemical responses that efficiently prevented lipid peroxidation. In Santander Bay (N Spain), exposure to PAHs and, presumably, pharmaceuticals induced biomarker responses, but lipid peroxidation occurred nevertheless. These results indicated that caged A. marina were effective for the assessment of Sediment Quality and that the selected biomarkers were sufficiently sensitive to identify chemical exposure and toxicity.
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Sediment Quality assessment using the polychaete arenicola marina contamination bioavailability and toxicity
Archives of Environmental Contamination and Toxicology, 2011Co-Authors: Julia Ramosgomez, Laura M Martindiaz, Javier R. Viguri, Carlos Vale, Angel Luque, Angel T DelvallsAbstract:The Sediment Quality of Cadiz Bay, Las Palmas de Gran Canaria (LPGC) Port, Santander Bay, Algeciras Bay, and Huelva Estuary (Spain) was evaluated by analysing a battery of biochemical biomarkers―activities of biotranformation enzymes ethoxyresorufin O-deethylase [EROD], dibenzylflourescein dealkylase [DBF], and glutathione S-transferase [GST]; activity of antioxidant enzyme glutathione reductase [GR]; and lipid peroxidation [LPO]―in the polychaete Arenicola marina after laboratory Sediment exposure. Huelva Estuary polychaetes showed significantly (p < 0.05) enhanced LPO, GST, and EROD activities compared with control lugworms related to metals and presumably polychlorinated biphenyls. EROD activity significant (p < 0.05) induction was associated polycyclic aromatic hydrocarbons after Santander Bay Sediment exposure. Nickel appeared to significantly (p < 0.05) induce GR activity and LPO in LPGC Port Sediment–exposed organisms. DBF activity significantly (p < 0.05) increased in polychaetes exposed to Sediments from sewage-contaminated areas. A. marina was sensitive at the biochemical level. Integration of Sediment characterization and biomarker results allowed the identification of polluted sites as well as the cause of possible Sediment toxicity.
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software data and modelling news sqa a software tool for integrated Sediment Quality evaluation based on the weight of evidence procedure
Environmental Modelling and Software, 2010Co-Authors: Alla Khosrovyan, Laura M Martindiaz, Angel T Delvalls, Carmen Moralescaselles, I RibaAbstract:A new software tool for integrative Sediment Quality assessment is developed. The program is based on WOE methodologies which together may be used for assessing degree of contamination in marine Sediment. Statistical analysis of field-collected and lab-based data is performed by means of commercial statistical software package Statistica 6.0. The designed tool provides user-friendly interface, is extremely easy in use, greatly simplifies statistical analysis process, interprets the results in text and graphical format.
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Sediment Quality assessment and dredged material management in spain part ii analysis of action levels for dredged material management and application to the bay of cadiz
Integrated Environmental Assessment and Management, 2007Co-Authors: Manuel Alvarezguerra, Javier R. Viguri, Carmen M Casadomartinez, Angel T DelvallsAbstract:When Sediments are removed from aquatic bottoms, they turn into dredged material that must be managed, taking into account its environmental impact. In Part II of this 2-part paper addressing Sediment Quality assessment and dredged material management in Spain, legislation and criteria used to regulate dredged material disposal at sea in different European countries are reviewed, as are action levels (ALs) derived by different countries used to evaluate management of dredged Sediments from Cadiz Bay located on the South Atlantic coast of Spain. Comparison of ALs established for dredged material disposal by different countries reveals orders of magnitude differences in the values established for the same chemical. In Part I of this 2-part paper, review of different Sediment Quality guideline (SQG) methods used to support Sediment Quality assessments indicated a great heterogeneity of SQGs, both with regard to the numeric values for a particular chemical and the number of substances for which SQGs have been derived. The analysis highlighted the absence of SQGs for priority substances identified in current European Union water policy. Here, in Part II, the ALs are applied to dredged Sediments from Cadiz Bay (South Atlantic coast of Spain), evidencing that the heterogeneity of ALs implemented in the reviewed countries could determine different management strategies. The application of other measurements such as bioassays might offer information useful in identifying a cost-effective management option in a decision-making framework, especially for dredged material with intermediate chemical concentrations.
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Sediment Quality assessment and dredged material management in spain part i application of Sediment Quality guidelines in the bay of santander
Integrated Environmental Assessment and Management, 2007Co-Authors: Manuel Alvarezguerra, Javier R. Viguri, Carmen M Casadomartinez, Angel T DelvallsAbstract:Sediments are an essential component of aquatic ecosystems that must be assessed and managed properly. The use of quantitative environmental Quality standards derived from consideration of Sediment Quality guidelines (SQGs) can be effective as part of a tiered risk assessment approach. In Part I of this 2-part paper addressing Sediment Quality assessment and dredged material management in Spain, different SQG methods are used to evaluate Sediment Quality in the Bay of Santander, located in the Cantabric Sea along the northern coast of Spain, and to guide development of empirically derived SQGs for marine Sediments. The results of the study indicate a great heterogeneity of SQGs, both with regard to the numeric values for a particular chemical and the number of substances for which SQGs have been derived. The analysis highlights the scarce development of empirical SQGs for priority substances identified in current European Union water policy. Nonetheless, the application of SQGs makes it possible to classify different zones of Sediment Quality in the Bay of Santander. Part II of this 2-part paper considers the environmental impacts of dredged material disposal. Legislation and criteria used to regulate dredged material disposal at sea in different European countries are reviewed, and action levels derived by different countries were used to evaluate management of dredged Sediments from Cadiz Bay, located on the South Atlantic coast of Spain.
Xuelu Gao - One of the best experts on this subject based on the ideXlab platform.
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Sediment Quality of the bohai sea and the northern yellow sea indicated by the results of acid volatile sulfide and simultaneously extracted metals determinations
Marine Pollution Bulletin, 2020Co-Authors: Xuelu Gao, Jinming Song, Huamao Yuan, Jianmin Zhao, Qianguo XingAbstract:Abstract The surface Sediments from the Bohai Sea (BS) and the northern Yellow Sea (NYS) were analyzed for acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) to assess the Sediment Quality. The results indicated that >60% of the samples were found to have possible adverse effects on aquatic life in the BS based on the difference between the concentrations of AVS ([AVS]) and SEM ([SEM]), and the corresponding percentage in the NYS was
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Sediment Quality of the sw coastal laizhou bay bohai sea china a comprehensive assessment based on the analysis of heavy metals
PLOS ONE, 2015Co-Authors: Xuelu Gao, Chentung Arthur Chen, Wen Zhuang, Yong ZhangAbstract:Historically, the Bohai Sea is one of the most important fishing grounds in China. Yet, surrounded by one of the biggest economic rims of China, its ecological functions have been declining rapidly in recent two decades under the heavy anthropogenic impacts. The Laizhou Bay is the smallest one of the three main bays in the Bohai Sea. Owing to the rich brine deposits, chemical industries using brine as raw materials are booming in the southern coast of the Laizhou Bay, the scale of which ranks as the largest one in China. In order to monitor and assess the environmental Quality, surface Sediments were collected from the coastal waters of southwestern Laizhou Bay and the rivers it connects with during summer and autumn in 2012, and analyzed for heavy metals. Several widely adopted methods were used in the overall assessment of heavy metal pollution status and potential ecological risks in these Sediments, and the data were analyzed to infer the main sources of the pollutants. The results showed that the remarkably high concentrations of heavy metals were almost all recorded in a small number of riverine sites. Cr, Cu, Ni and Zn were the main environmental threat according to the Sediment Quality guidelines. The marine area was generally in good condition with no or low risk from the studied metals and adverse effects on biota could hardly occur. Natural sources dominated the concentrations and distributions of Cu, Ni, Pb and Zn in the marine area. Our results indicated that heavy metal pollution was not a main cause of the ecological degradation of the Laizhou Bay at present.
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assessment of Sediment Quality in two important areas of mariculture in the bohai sea and the northern yellow sea based on acid volatile sulfide and simultaneously extracted metal results
Marine Pollution Bulletin, 2013Co-Authors: Xuelu Gao, Chentung Arthur ChenAbstract:The surface Sediments from Laizhou Bay (LB) and the coastal sea around Zhangzi Island (ZI) were analyzed for acid-volatile sulfide (AVS) and simultaneously extracted metals (SEMs) to assess the Sediment Quality. These two areas, especially LB, are important mariculture bases in China and are significantly affected by the Yellow River. The concentrations of AVS ([AVS]) and SEM ([SEM]) varied in the ranges 0.71-11.03 and 0.10-0.74 mu mol g(-1) dry weight, respectively. [AVS] was generally low in the river outlet area and increased in the seaward direction in LB. [AVS] was significantly and positively correlated with TOC. [SEM] was significantly and positively correlated with TOC, the water content of Sediment and the fine Sediment fraction and it was significantly and negatively correlated with coarse Sediment fraction. The obtained results suggest that the surface Sediments of LB and ZI were of high Quality and not likely to cause negative effects on their ecosystems. (c) 2013 Elsevier Ltd. All rights reserved.
Christopher G Ingersoll - One of the best experts on this subject based on the ideXlab platform.
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improving Sediment Quality guidelines for nickel development and application of predictive bioavailability models to assess chronic toxicity of nickel in freshwater Sediments
Environmental Toxicology and Chemistry, 2013Co-Authors: M Vangheluwe, John M Besser, William G Brumbaugh, Christopher G Ingersoll, Christian E Schlekat, Frederik Verdonck, Emily R GarmanAbstract:Within the framework of European Union chemical legislations an extensive data set on the chronic toxicity of Sediment nickel has been generated. In the initial phase of testing, tests were conducted with 8 taxa of benthic invertebrates in 2 nickel-spiked Sediments, including 1 reasonable worst-case Sediment with low concentrations of acid-volatile sulfide (AVS) and total organic carbon. The following species were tested: amphipods (Hyalella azteca, Gammarus pseudolimnaeus), mayflies (Hexagenia sp.), oligochaetes (Tubifex tubifex, Lumbriculus variegatus), mussels (Lampsilis siliquoidea), and midges (Chironomus dilutus, Chironomus riparius). In the second phase, tests were conducted with the most sensitive species in 6 additional spiked Sediments, thus generating chronic toxicity data for a total of 8 nickel-spiked Sediments. A species sensitivity distribution was elaborated based on 10% effective concentrations yielding a threshold value of 94 mg Ni/kg dry weight under reasonable worst-case conditions. Data from all Sediments were used to model predictive bioavailability relationships between chronic toxicity thresholds (20% effective concentrations) and AVS and Fe, and these models were used to derive site-specific Sediment-Quality criteria. Normalization of toxicity values reduced the interSediment variability in toxicity values significantly for the amphipod species Hyalella azteca and G. pseudolimnaeus, but these relationships were less clearly defined for the mayfly Hexagenia sp. Application of the models to prevailing local conditions resulted in threshold values ranging from 126 mg to 281 mg Ni/kg dry weight, based on the AVS model, and 143 mg to 265 mg Ni/kg dry weight, based on the Fe model. Environ Toxicol Chem 2013;32:2507–2519. © 2013 SETAC
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calculation and uses of mean Sediment Quality guideline quotients a critical review
Environmental Science & Technology, 2006Co-Authors: Edward R Long, Christopher G Ingersoll, Donald D MacdonaldAbstract:Fine-grained Sediments contaminated with complex mixtures of organic and inorganic chemical contaminants can be toxic in laboratory tests and/or cause adverse impacts to resident benthic communities. Effects-based, Sediment Quality guidelines (SQGs) have been developed over the past 20 years to aid in the interpretation of the relationships between chemical contamination and measures of adverse biological effects. Mean Sediment Quality guideline quotients (mSQGQ) can be calculated by dividing the concentrations of chemicals in Sediments by their respective SQGs and calculating the mean of the quotients for the individual chemicals. The resulting index provides a method of accounting for both the presence and the concentrations of multiple chemicals in Sediments relative to their effects-based guidelines. Analyses of considerable amounts of data demonstrated that both the incidence and magnitude of toxicity in laboratory tests and the incidence of impairment to benthic communities increases incrementally with increasing mSQGQs. Such concentration/response relationships provide a basis for estimating toxicological risks to Sediment-dwelling organisms associated with exposure to contaminated Sediments with a known degree of accuracy. This Sediment Quality assessment tool has been used in numerous surveys and studies since 1994. Nevertheless, mean SQGQs have some important limitations and underlying assumptions that should be understood by Sediment Quality assessors. This paper provides an overview of the derivation methods and some of the principal advantages, assumptions, and limitations in the use of this Sediment assessmenttool. Ideally, mean SQGQs should be included with other measures including results of toxicity tests and benthic community surveys to provide a weight of evidence when assessing the relative Quality of contaminated Sediments.
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evaluation of numerical Sediment Quality targets for the st louis river area of concern
Archives of Environmental Contamination and Toxicology, 2002Co-Authors: Judy L. Crane, Donald D Macdonald, Christopher G Ingersoll, T A Berger, D E Smorong, R A Lindskoog, Corinne G Severn, L J FieldAbstract:Numerical Sediment Quality targets (SQTs) for the protection of Sediment-dwelling organisms have been established for the St. Louis River Area of Concern (AOC), 1 of 42 current AOCs in the Great Lakes basin. The two types of SQTs were established primarily from consensus-based Sediment Quality guidelines. Level I SQTs are intended to identify contaminant concentrations below which harmful effects on Sediment-dwelling organisms are unlikely to be observed. Level II SQTs are intended to identify contaminant concentrations above which harmful effects on Sediment-dwelling organisms are likely to be observed. The predictive ability of the numerical SQTs was evaluated using the matching Sediment chemistry and toxicity data set for the St. Louis River AOC. This evaluation involved determination of the incidence of toxicity to amphipods (Hyalella azteca) and midges (Chironomus tentans) within five ranges of Level II SQT quotients (i.e., mean probable effect concentration quotients [PEC-Qs]). The incidence of toxicity was determined based on the results of 10-day toxicity tests with amphipods (endpoints: survival and growth) and 10-day toxicity tests with midges (endpoints: survival and growth). For both toxicity tests, the incidence of toxicity increased as the mean PEC-Q ranges increased. The incidence of toxicity observed in these tests was also compared to that for other geographic areas in the Great Lakes region and in North America for 10- to 14-day amphipod (H. azteca) and 10- to 14-day midge (C. tentans or C. riparius) toxicity tests. In general, the predictive ability of the mean PEC-Qs was similar across geographic areas. The results of these predictive ability evaluations indicate that collectively the mean PEC-Qs provide a reliable basis for classifying Sediments as toxic or not toxic in the St. Louis River AOC, in the larger geographic areas of the Great Lakes, and elsewhere in North America.
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development and evaluation of consensus based Sediment Quality guidelines for freshwater ecosystems
Archives of Environmental Contamination and Toxicology, 2000Co-Authors: Donald D Macdonald, Christopher G Ingersoll, T A BergerAbstract:Numerical Sediment Quality guidelines (SQGs) for freshwater ecosystems have previously been developed using a variety of approaches. Each approach has certain advantages and limitations which influence their application in the Sediment Quality assessment process. In an effort to focus on the agreement among these various published SQGs, consensus-based SQGs were developed for 28 chemicals of concern in freshwater Sediments (i.e., metals, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and pesticides). For each contaminant of concern, two SQGs were developed from the published SQGs, including a threshold effect concentration (TEC) and a probable effect concentration (PEC). The resultant SQGs for each chemical were evaluated for reliability using matching Sediment chemistry and toxicity data from field studies conducted throughout the United States. The results of this evaluation indicated that most of the TECs (i.e., 21 of 28) provide an accurate basis for predicting the absence of Sediment toxicity. Similarly, most of the PECs (i.e., 16 of 28) provide an accurate basis for predicting Sediment toxicity. Mean PEC quotients were calculated to evaluate the combined effects of multiple contaminants in Sediment. Results of the evaluation indicate that the incidence of toxicity is highly correlated to the mean PEC quotient (R(2) = 0.98 for 347 samples). It was concluded that the consensus-based SQGs provide a reliable basis for assessing Sediment Quality conditions in freshwater ecosystems.
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development and evaluation of consensus based Sediment Quality guidelines for freshwater ecosystems
Archives of Environmental Contamination and Toxicology, 2000Co-Authors: Donald D Macdonald, Christopher G Ingersoll, T A BergerAbstract:Numerical Sediment Quality guidelines (SQGs) for freshwater ecosystems have previously been developed using a variety of approaches. Each approach has certain advantages and limitations which influence their application in the Sediment Quality assessment process. In an effort to focus on the agreement among these various published SQGs, consensus-based SQGs were developed for 28 chemicals of concern in freshwater Sediments (i.e., metals, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and pesticides). For each contaminant of concern, two SQGs were developed from the published SQGs, including a threshold effect concentration (TEC) and a probable effect concentration (PEC). The resultant SQGs for each chemical were evaluated for reliability using matching Sediment chemistry and toxicity data from field studies conducted throughout the United States. The results of this evaluation indicated that most of the TECs (i.e., 21 of 28) provide an accurate basis for predicting the absence of Sediment toxicity. Similarly, most of the PECs (i.e., 16 of 28) provide an accurate basis for predicting Sediment toxicity. Mean PEC quotients were calculated to evaluate the combined effects of multiple contaminants in Sediment. Results of the evaluation indicate that the incidence of toxicity is highly correlated to the mean PEC quotient (R(2) = 0.98 for 347 samples). It was concluded that the consensus-based SQGs provide a reliable basis for assessing Sediment Quality conditions in freshwater ecosystems.
Edward R Long - One of the best experts on this subject based on the ideXlab platform.
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revision of Sediment Quality triad indicators in puget sound washington usa i a Sediment chemistry index and targets for mixtures of toxicants
Integrated Environmental Assessment and Management, 2013Co-Authors: Edward R Long, Margaret Dutch, Valerie Partridge, Sandra Weakland, Kathy WelchAbstract:The Washington State Department of Ecology annually conducts Sediment Quality monitoring in Puget Sound as a component of the Puget Sound Ecosystem Monitoring Program. Sediment samples are analyzed to determine the concentrations of about 170 chemical and physical variables. A Sediment Chemistry Index (SCI) was derived using the State of Washington Sediment Management Standards to account for the presence and concentrations of mixtures of toxicants. Mean Sediment Quality Standard quotients (mSQSq) were calculated as the basis for the SCI and compared to the incidence and degree of toxicity in laboratory tests and to metrics of the diversity and abundance of resident benthic assemblages in a database consisting of as many as 664 samples. These data were evaluated with co-occurrence analyses to identify “cut points” (i.e., thresholds) in the index below which the frequency and magnitude of biological effects were relatively low and above which they occurred with increasing frequency or magnitude. Iterative trials of different sets of cut points established the final cut points in mSQSq of 0.1, 0.3, and 0.5. They defined 4 ranges in chemical exposure: Minimum (<0.1), Low (0.1– < 0.3), Moderate (0.3– < 0.5), and Maximum (≥0.5). Across these 4 exposure ranges both the incidence and magnitude of toxicity in some laboratory tests increased, the abundance of most stress-sensitive benthic taxa decreased, and the abundance of most stress-tolerant taxa increased. The mSQSq cut point of 0.1 appears to be the target value for protection of benthic resources, the value below which the probability and magnitude of adverse effects either in the laboratory or the field are the lowest. The mSQSq values are rescaled from 0 to 100 to form the SCI, used by the Puget Sound Partnership and environmental managers as a Dashboard Indicator, with biologically relevant targets selected to monitor ecosystem recovery. Integr Environ Assess Manag 2013; 9: 31–49. © 2012 SETAC
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metallic and organic contaminants in Sediments of sydney harbour australia and vicinity a chemical dataset for evaluating Sediment Quality guidelines
Environment International, 2006Co-Authors: S Mccready, G F Birch, Edward R LongAbstract:An internally consistent dataset comprising 103 surficial estuarine Sediment samples were collected from Sydney Harbour, Australia and locations south of Sydney. This paper describes the chemical characteristics of the dataset and evaluates its suitability for use in evaluating biological effects-based Sediment Quality guidelines (SQGs). The Sediments contained mixtures of chemicals, the most prevalent chemical classes being metals and polycyclic aromatic hydrocarbons, whereas Sediments from coastal lakes/estuaries south of Sydney had low concentrations of contaminants. Maximum concentrations of the prevalent contaminants zinc, lead, copper and pyrene were 11,300, 1,420, 1,060 mg kg(-1) and 23,300 microg kg(-1), respectively. For the majority of samples, concentrations of individual chemicals exceeded most effects-based SQGs that have been adopted for use in Australia, implying occasional or frequent adverse biological effects are expected. Comparing mixtures of contaminants to ranges in numbers of SQGs exceeded and mean SQG quotients showed that most samples (57% to 68%) had contamination characteristics associated with moderate probabilities (30% to 52%) of acute toxicity, based on North American data. A smaller proportion of samples (15% to 17%) had contamination characteristics associated with high probabilities (74% to 85%) of toxicity. The wide range of chemicals and concentrations, associated with low, medium and high probabilities of toxicity, indicated that the dataset was suitable for future use in evaluating predictive abilities of SQGs. This is relevant, given the recent introduction of North American-derived SQGs for Australia.
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calculation and uses of mean Sediment Quality guideline quotients a critical review
Environmental Science & Technology, 2006Co-Authors: Edward R Long, Christopher G Ingersoll, Donald D MacdonaldAbstract:Fine-grained Sediments contaminated with complex mixtures of organic and inorganic chemical contaminants can be toxic in laboratory tests and/or cause adverse impacts to resident benthic communities. Effects-based, Sediment Quality guidelines (SQGs) have been developed over the past 20 years to aid in the interpretation of the relationships between chemical contamination and measures of adverse biological effects. Mean Sediment Quality guideline quotients (mSQGQ) can be calculated by dividing the concentrations of chemicals in Sediments by their respective SQGs and calculating the mean of the quotients for the individual chemicals. The resulting index provides a method of accounting for both the presence and the concentrations of multiple chemicals in Sediments relative to their effects-based guidelines. Analyses of considerable amounts of data demonstrated that both the incidence and magnitude of toxicity in laboratory tests and the incidence of impairment to benthic communities increases incrementally with increasing mSQGQs. Such concentration/response relationships provide a basis for estimating toxicological risks to Sediment-dwelling organisms associated with exposure to contaminated Sediments with a known degree of accuracy. This Sediment Quality assessment tool has been used in numerous surveys and studies since 1994. Nevertheless, mean SQGQs have some important limitations and underlying assumptions that should be understood by Sediment Quality assessors. This paper provides an overview of the derivation methods and some of the principal advantages, assumptions, and limitations in the use of this Sediment assessmenttool. Ideally, mean SQGQs should be included with other measures including results of toxicity tests and benthic community surveys to provide a weight of evidence when assessing the relative Quality of contaminated Sediments.
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an evaluation of methods for calculating mean Sediment Quality guideline quotients as indicators of contamination and acute toxicity to amphipods by chemical mixtures
Environmental Toxicology and Chemistry, 2001Co-Authors: Russell Fairey, Edward R Long, Brian S Anderson, Bryn M Phillips, John W Hunt, C Roberts, Howard R Puckett, Craig J WilsonAbstract:Mean Sediment Quality guideline quotients (mean SQGQs) were developed to represent the presence of chemical mixtures in Sediments and are derived by normalizing a suite of chemicals to their respective numerical Sediment Quality guidelines (SQGs). Mean SQGQs incorporate the number of SQGs exceeded and the degree to which they are exceeded and are used for comparison with observed biological effects in the laboratory or field. The current research makes it clear, however, that the number and type of SQGs used in the derivation of these mean quotients can influence the ability of mean SQGQ values to correctly predict acute toxicity to marine amphipods in laboratory toxicity tests. To determine the optimal predictive ability of mean SQGQs, a total of 18 different chemical combinations were developed and compared. The ability of each set of mean SQGQs to correctly predict the presence and absence of acute toxicity to amphipods was determined using three independent databases (n = 605, 2753, 226). Calculated mean SQGQ values for all chemical combinations ranged from 0.002 to 100. The mean SQGQ that was most predictive of acute toxicity to amphipods is calculated as SQGQ1 = ((γ ([cadmium]/4.21)([copper]/270)([lead]/112.18)([silver]/1.77)([zinc]/410)([total chlordane]/6)([dieldrin]/8)([total PAHoc]/1,800)([total PCB]/400))/9). Both the incidence and magnitude of acute toxicity to amphipods increased with increasing SQGQ1 values. To provide better comparability between regions and national surveys, SQGQ1 is recommended to serve as the standard method for combination of chemicals and respective SQGs when calculating mean SQGQs.
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classifying probabilities of acute toxicity in marine Sediments with empirically derived Sediment Quality guidelines
Environmental Toxicology and Chemistry, 2000Co-Authors: Edward R Long, Donald D Macdonald, Corinne G Severn, Carolyn B HongAbstract:Matching, marine Sediment chemistry, and toxicity data (n = 1,513), compiled from three studies conducted in the United States, were analyzed to determine both the frequency of acute toxicity to amphipods and average percentage survival in laboratory bioassays within ranges in toxicant concentrations. We determined that the probability of observing acute toxicity was relatively low (<10%) and that average control-adjusted survival equaled or exceeded 92% in samples in which Sediment Quality guidelines were not exceeded. Both the incidence of toxicity increased and average survival decreased as chemical concentrations increased relative to the guidelines. In Sediments with highest contaminant concentrations, 73 to 83% of the samples were highly toxic, and average control-adjusted amphipod survival was 37 to 46%. Results of this study confirm that the relationships between Sediment chemical concentrations and toxicity reported in a previous study were robust. Further, they indicate that numerical guidelines for saltwater Sediments can be used to estimate the probability of observing toxic effects in acute amphipod tests.
