Development Of Sediment Quality Criteria Research Articles

Relative toxicity of bifenthrin to Hyalella azteca in 10 day versus 28 day exposures.

Many watersheds in the Central Valley region of California are listed as impaired due to pyrethroid-associated sediment toxicity. The Central Valley Regional Water Quality Control Board is developing numeric sediment quality criteria for pyrethroids, beginning with bifenthrin. Criteria are being developed using existing data, along with data from 10 d and 28 d toxicity tests with Hyalella azteca conducted as part of the current study. A single range-finder and 2 definitive tests were conducted for each test duration. Median lethal concentrations (LC50s), as well as LC20s and inhibition concentrations (IC20s) were calculated based on measured whole sediment bifenthrin concentrations and interstitial water concentrations. Sediment LC50s were also corrected for organic C content. Average LC50s were not significantly different in 10 d versus 28 d tests with H. azteca: 9.1 and 9.6 ng/g bifenthrin for 10 d and 28 d tests, respectively. Average LC20 values were also similar with concentrations at 7.1 and 7.0 for 10 d and 28 d tests, respectively. Bifenthrin inhibition concentrations (IC20s) based on amphipod growth were variable, particularly in the 28 d tests, where a clear dose-response relationship was observed in only 1 of the definitive experiments. Average amphipod growth IC20s were 3.9 and 9.0 ng/g for 10 d and 28 d tests, respectively. Amphipod growth calculated as biomass resulted in IC20s of 4.1 and 6.3 ng/g for the 10 d and 28 d tests, respectively. Lack of a clear growth effect in the longer term test may be related to the lack of food adjustment to account for amphipod mortality in whole sediment exposures. The average C-corrected LC50s were 1.03 and 1.09 μg/g OC for the 10 d and 28 d tests, respectively. Interstitial water LC50s were determined as the measured dissolved concentration of bifenthrin relative to interstitial water dissolved organic carbon. The average LC50s for dissolved interstitial water bifenthrin were 4.23 and 4.28 ng/L for the 10 d and 28 d tests, respectively. In addition, a set of 10 d and 28 d tests were conducted at 15 °C to assess the relative toxicity of bifenthrin at a lower temperature than the standard 23 °C test temperature. These results showed that bifenthrin was more toxic at the lower temperature, with LC50s of 5.1 and 3.4 ng/g bifenthrin in 10 d and 28 d tests, respectively. Amphipod growth at 15 °C after a 28 d exposure resulted in the lowest effect concentration of all experiments conducted (IC20 = 0.61 ng/g). This article discusses how bifenthrin dose-response data from 10 d and 28 d exposures inform development of sediment quality criteria for this pesticide for California Central Valley watersheds.

The interplay of environmental toxicology and chemistry in the development of sediment quality criteria

Abstract The search for rational methods to develop criteria for various media-water, sediment, and tissue-and various receptors-aquatic, terrestrial, and human-has been a consistent and continuous enterprise from the beginning of environmental toxicology. Many of the 100 most frequently cited papers in Environmental Toxicology and Chemistry directly or indirectly address topics relevant to criteria. Subsets of these papers are concerned with the interaction between environmental toxicology and environmental chemistry. Environ. Toxicol. Chem. © 2012 SETAC.

Transitioning sediment quality assessment into regulations: Challenges and solutions in implementing California's sediment quality objectives

Development and promulgation of sediment quality criteria represents a substantial challenge for water quality agencies. Unlike water quality programs that rely on individual chemical thresholds to assess water quality, the complex processes affecting contaminant bioavailability in sediments preclude the use of contaminant concentrations to independently assess impacts or identify cause. Various multiple line of evidence approaches (e.g., sediment quality triad) have been developed for sediment quality assessment, but such frameworks are rarely fully incorporated into statewide regulatory programs due to a lack of standardized and validated tools. In 2003, California's State Water Resources Control Board (State Water Board) initiated development of sediment quality criteria and an assessment framework that required the developers to resolve many challenging technical and policy related issues to the satisfaction of stakeholders, scientists, and the general public. The first part of this multiyear effort has been completed and resulted in the development and validation of an integrated collection of tools, thresholds, and a data interpretation framework for assessing sediment contamination impacts on benthic community condition. The State Water Board's narrative sediment quality criteria and assessment framework became effective in 2009, following US Environmental Protection Agency approval. The results of this effort are described in a series of 6 articles published in this issue of Integrated Environmental Assessment and Management. The articles describe: 1) a multiple line of evidence framework for data integration and assessment, 2) calibration and evaluation of sediment quality guidelines for predicting toxic responses, 3) development and evaluation of sediment quality guidelines with respect to benthic macrofauna responses, 4) selection of toxicity test methods and thresholds, 5) identification and characterization of benthic community assemblages, 6) the effect of sampling methods on benthic community assessment, and 7) recommendations on improving the assessment of contaminant exposure in sediment quality assessment. This collection of articles illustrates the steps needed to improve the scientific foundation for sediment quality assessment in regulatory applications.

Development of sediment quality criteria in Norway

A Norwegian system for classification of environmental quality of contaminated marine sediments has been in force since 1997 and was revised in 2007. The 1997 classification had five quality classes based on the statistical distribution of levels of the contaminants in sediments along the Norwegian coast.Class I represents background and classes II-V describe four intervals of concentrations mainly from a percentile division of the total distribution. The revised classification is based on toxicity of the contaminants. It covers 43 compounds against 28 in the 1997 version. It is based on European Union systems for defining environmental quality standards and performing risk assessment. Five classes are retained. Class I is kept as the background range. The upper limits for class II and class III are the Predicted No Effect Concentrations (PNEC) for chronic respectively acute (intermittent) exposure from the compound. The upper limit of class IV is 2-5 × PNEC intermittent depending on compound, and class V is everything above this. The border between class II and class III is most significant as it separates no-effects sediments from those for which sediment remediation may be needed. The classification has been changed from concentration based to effects based and is in harmony with the Norwegian guideline for risk assessment of sediments. The classification system should be intermittently revised to include new or improved environmental quality standards as they are approved by the European Commission.

Comparative Study of Sediment Quality From the Tietê River Reservoirs (SP)

There is a general consensus that the sediment from water bodies plays a fundamental role in the transport dynamics, accumulation and availability of pollutants. In the sediments quality triad, considered one of the best approaches for the study of anthropogenic contaminated aquatic systems, the chemical and biological data (bioassays and benthic community analysis) are combined to show the degradation of each site. The RTM (ratio to maximum value) values provide useful visual information, because they can be plotted in axes with common origin. Therefore, a relative measure of sediment degradation can be obtained, by calculating the area formed by the figure obtained for each station or site. This comparative design of study was applied as an alternative to the multivariate analyses (PCA, Cluster, etc.) to the data obtained by the Qualised project – Technical-Scientific Bases For the Development of Sediment Quality Criteria – for the 2000 to 2001 period. The results allow the classification of the reservoirs based on their respective sediment quality and indicate the degradation vectors they are subject to. The spatial distribution of sediments potentially toxic accompanies the trophic gradient of Tietê River, i.e., the downstream reservoirs are less eutrophicated than the upstream ones. Therefore, the quality of the sediments improves with the distance from the metropolitan area of São Paulo confirming the origin of most of pollutant substances. The sediments of Rasgão and Billings reservoirs were considered those with lower quality, while those from Promissão reservoir present a better condition.

Do aquatic effects or human health end points govern the development of sediment-quality criteria for nonionic organic chemicals ?

The equilibrium partitioning theory may be used to describe the partitioning of nonionic organic chemicals between water, sediment, and aquatic biota. This paradigm was employed to compare the relative magnitudes of organic carbon-normalized sediment-quality criteria that are intended to protect either benthic organisms from the direct toxic effects of sediment-associated chemicals or humans from the indirect health effects posed by the ingestion of contaminated aquatic animals. Comparison of calculated sediment-quality criteria for a variety of hydrophobic chemicals suggests that human health-based end points often result in more restrictive criteria than aquatic effects-based values. Review of published field data indicates that the equilibrium partitioning paradigm may, depending on contaminant class, either over- or underestimate the extent to which sediment-associated contaminations are bioaccumulated. Despite the limitations of adopting this simple theory for criteria development, calculations reveal that regulatory decisions involving sediments contaminated with such chemicals may be dictated by human health concerns if current risk assessment methodologies are applied.

Predicting chronic toxicity of sediments spiked with zinc: An evaluation of the acid‐volatile sulfide model using a life‐cycle test with the midge Chironomus tentans

AbstractThe development of sediment quality criteria for the cationic metals cadmium, copper, lead, nickel, and zinc has focused on the use of acid‐volatile sulfide (AVS) as the primary normalization phase for predicting interstitial pore‐water concentrations and bioavailability of the metals. To date, most of the research in support of AVS in this context has utilized short‐term laboratory exposures, with a relative paucity of information pertaining to long‐term exposures. The purpose of this study, therefore, was to investigate the use of AVS as a predictor of metal toxicity to a benthic organism in a long‐term laboratory exposure. Clean sediment was spiked with zinc to obtain nominal treatments ranging from −2.34 to 58.5 μg/g dry weight with respect to the molar difference between simultaneously extracted metal (SEM) and AVS. The test was initiated with newly hatched larvae of the midge Chironomus tentans and carried through one complete generation (56 d) during which survival, growth, emergence, and reproduction were monitored. When the molar difference between SEM and AVS (i.e., SEM – AVS) was <0, the concentration of zinc in the sediment interstitial water was low and no adverse effects were observed for any of the biological endpoints measured. Conversely, when SEM – AVS exceeded 0, a dose‐dependent increase in the relative concentration of zinc in the pore water was detected. However, the absolute concentration of pore‐water zinc at each treatment declined over the course of the study, corresponding to an increase in sediment AVS and to a loss of zinc due to diffusion into the overlying water, which was renewed twice daily. Only when SEM – AVS exceeded 0 were significant reductions in survival, growth, emergence, and reproduction observed. Together, the chemical and biological data from this study compare favorably with observations made in short‐term exposures and thus support the use of AVS as a normalization phase for predicting toxicity in metal‐contaminated sediments.

Effects of acid‐volatile sulfide on zinc bioavailability and toxicity to benthic macroinvertebrates: A spiked‐sediment field experiment

AbstractAcid‐volatile sulfide (AVS) has been proposed as the primary normalization phase for the development of sediment quality criteria for certain cationic metals. This study was designed to assist in this development by providing necessary field data on the relationships among season, AVS concentrations, and zinc bioavailability and toxicity in freshwater sediments. Zinc was spiked into uncontaminated sediments collected from a local pond, creating five simultaneously extracted metal (SEM) concentrations ranging from 0.8 to 12.0 μmol/g dry weight. The spiked sediments were transferred to 4‐L plastic trays, returned to the bottom of the pond, and sampled on five dates during 1993‐1994. Results revealed a pronounced increase in AVS concentration with increasing zinc concentration. Acid‐volatile sulfide concentrations in zinc‐spiked sediments displayed only minor seasonal variation but were lowest in surficial (0‐2 cm) sediments. Acid‐volatile sulfide concentrations always exceeded SEM concentrations at ≤6.0 μmol SEM/g; only at 12.0 μmol SEM/g did SEM/AVS ratios exceed 1.0. Zinc was rarely detected in pore water at any treatment and never at concentrations which should have posed a hazard to benthic macroinvertebrates. No substantial effect on colonization of zinc‐spiked sediments by benthic macroinvertebrates was observed. Only oligochaetes (Naididae) were significantly reduced in abundance at the high zinc treatment, although reductions were occasionally evident for other taxa. Lack of noteworthy pore‐water zinc concentrations and lack of associated, ecologically meaningful effects were attributed to the increase in AVS levels observed with increasing SEM zinc sediment concentration. The increases in AVS theoretically resulted from a replacement of natural iron and manganese sulfides with the more stable zinc sulfide complex.

Development of sediment-quality criteria—A proposal from experimental field-studies of the effects of copper on benthic organisms

Very few of the numerous studies of the effects of copper on animals living in marine sediments have involved manipulative field-experiments. Such experiments provide greater realism than laboratory-based studies in terms of environmental variability or complexity, but the otherwise confounding effects of this variation can be removed by random allocation of treatments to experimental units. We describe an experiment in sandy sediments in Botany Bay, NSW, Australia, in which concentrations of copper in the sediments were manipulated using blocks of plaster impregnated with copper sulphate. Replicate copperenhanced and control treatments were randomly allocated to experimental units. Thus, any differences among treatments in the patterns of change in their faunas can be unambiguously ascribed to the copper treatment. The use of manipulative field-experiments is discussed in the context of the development of sediment-quality criteria.

Biological guidelines for freshwater sediment based on BEnthic Assessment of SedimenT (the BEAST) using a multivariate approach for predicting biological state

Abstract This paper describes the first results for an alternative approach to the development of sediment quality criteria in the nearshore areas of the Laurentian Great Lakes. The approach is derived from methods developed in the United Kingdom for establishing predictive relationships between macroinvertebrate fauna and the physico‐chemistry of riverine environments. The technique involves a multivariate statistical approach using (i) data on the structure of benthic invertebrate communities, (ii) functional responses (survival, growth and reproduction) in four sediment toxicity tests (bioassays) with benthic invertebrates; and (iii) selected environmental variables at 96 reference (‘clean’) sites in the nearshore areas of all five Great Lakes (Lakes Superior, Huron, Erie, Ontario and Michigan). Two pattern recognition techniques (using the computer software package PATN) are employed in the analysis: cluster analysis and ordination. The ordination vector scores from the original axes of the pattern analysis are correlated (using CORR in SAS) with environmental variables which are anticipated to be least affected by anthropogenic activities (e. g. alkalinity, depth, silt, sodium etc.). Multiple discriminant analysis (MDA) is used to relate the site groupings from the pattern analysis to the environmental variables and to generate a model that can be used to predict community assemblages and functional responses at new sites with unknown but potential contamination. The predicted community assemblages and functional responses are then compared with the actual benthic communities and responses at a site, and the need for remedial action is determined.The predictive capability of the discriminant model was confirmed by performing several validation runs on subsets of the data. An example of the use of the model for sediment in Collingwood Bay (an area of concern designated by the IJC in Georgian Bay, Lake Huron) is presented and the technique is shown to be more precise in determining the need for remediation than the currently used provincial sediment quality criteria based on Screening Level Concentration (SLC) and laboratory toxicity tests. The ultimate goal of the study is the development of a method to determine the need for, and the success of, remedial action and to predict what benthic communities should look like at a site if it were clean and what responses of organisms in sediment toxicity tests constitute an acceptable end‐point.

Check studies with Hyalella azteca and Chironomus tentans in support of the development of a sediment quality criterion for dieldrin

AbstractThe development of sediment quality criteria (SQCs) for nonpolar compounds using equilibrium partitioning theory (EqP) requires three critical data elements for the compound of interest: (a) a reliable, measured Kow; (b) an acceptable minimum data set for the development of the final acute and final chronic values necessary to calculate a water‐quality criterion (WQC); and (c) “check” experiments with appropriate freshwater and marine benthic organisms to ensure that their responses in spiked‐sediment tests are in agreement with responses predicted based on EqP. This study presents the results of dieldrin check experiments with two freshwater species: the amphipod Hyalella azteca and the chironomid Chironomus tentans. Ten‐day, flowthrough, water‐only dieldrin LC50 values for the amphipod and chironomid were 7.6 and 1.1 μg/L, respectively. The LC50 values for the two species based on organic carbon‐normalized sediment concentrations of dieldrin were generally less variable than values based on dieldrin concentrations in sediments on a dry‐weight basis. Ten‐day LC50 values for H. azteca and C. tentans based on measured pore‐water concentrations of dieldrin were greater than those based on EqP‐predicted pore‐water concentrations of dieldrin. An increase in the apparent water solubility of dieldrin as a result of binding to dissolved organic carbon appeared to account for this phenomenon. Ten‐day LC50 values for H. azteca and C. tentans based on EqP‐predicted pore‐water concentrations of dieldrin were within a factor of 25 and 3 of their respective 10‐d, water‐only dieldrin LC50 values. Avoidance of the dieldrin‐spiked sediments may offer a partial explanation for the concentration‐response results observed with H. azteca and the greater difference observed for this species between water‐only and predicted pore‐water 10‐d LC50 values for dieldrin. Inhibition of growth in C. tentans was also a sensitive end point with effects observed at pore‐water concentrations of dieldrin as small as 5.5 μg/g organic carbon. Based on these results, it appears that EqP based upon sediment organic carbon content is an appropriate model for converting WQC for dieldrin to SQC. These results also highlight the importance of using multiple benthic test species (including at least one infaunal species), end points, and sediments in SQC sediment‐spiking check studies.

Use of freshwater plants for phytotoxicity testing: A review

Phytotoxicity data for aquatic plants have served a relatively minor role in regulatory decisions concerning the environmental hazard of most potential contaminants. A variety of phytotoxicity tests have been conducted with freshwater green algae, duckweed, blue-green algae, diatoms and rooted macrophytes (whole plants and seeds). Several test methods have been standardized for microalgae which are used primarily with chemicals, effluents, contaminated sediment elutriates and hazardous waste leachates. Current scientific understanding concerning the phytotoxic effects of these contaminants is based mostly on results for a few green algae. The greatest limitation of these results is their uncertain environmental relevance due to the large interspecific variation in response of standard algal test species and the unrealistic experimental test conditions. Results of the few field validation toxicity tests conducted to resolve this uncertainty have been chemical-specific and unpredictable. Aquatic vascular plants have been used less frequently than algae as test species. Duckweeds have been used more often than rooted submersed species but the uncertain nature of their sensitivities relative to animal and other plant species has limited their use. Regulatory interest in wetland protection, contaminated sediment evaluations and sediment quality criteria development will result in increased use of whole rooted plants and their seeds as test species. Overall, regardless of the test species, if phytotoxicity data are to be more available and effective in the hazard assessment process, additional information concerning species sensitivity, and environmental relevance of the results will be needed.

Assessing potential bioavailability of metals in sediments: A proposed approach

Due to anthropogenic inputs, elevated concentrations of metals frequently occur in aquatic sediments. In order to make defensible estimates of the potential risk of metals in sediments and/or develop sediment quality criteria for metals, it is essential to identify that fraction of the total metal in the sediments that is bioavailable. Studies with a variety of benthic invertebrates indicate that interstitial (pore) water concentrations of metals correspond very well with the bioavailability of metals in test sediments. Many factors may influence pore water concentrations of metals; however, in anaerobic sediments a key phase controlling partitioning of several cationic metals (cadmium, nickel, lead, zinc, copper) into pore water is acid volatile sulfide (AVS). In this paper, we present an overview of the technical basis for predicting bioavailability of cationic metals to benthic organisms based on pore water metal concentrations and metal-AVS relationships. Included are discussions of the advantages and limitations of metal bioavailability predictions based on these parameters, relative both to site-specific assessments and the development of sediment quality criteria.

Seasonal variation of acid volatile sulfide concentration in sediment cores from three northeastern Minnesota lakes

Acid volatile sulfide (AVS) is a natural agent in sediments which complexes some cationic metals and thereby influences the toxicity of these metals to benthic organisms. Because of its influence on metal bioavailability, AVS has been proposed as a key normalization phase for the development of sediment quality criteria for metals. However, studies conducted primarily in marine and estuarine systems have shown that AVS concentrations can vary markedly both temporally and with (sediment) depth. In this study, AVS concentrations were measured monthly for 16 mo in several segments of sediment cores from three freshwater lakes: Caribou Lake, Fish Lake and Pike Lake in northeastern Minnesota, USA. The concentrations of AVS in cores from the three lakes varied inversely with sediment depth. AVS concentrations also varied seasonally by as much as two orders of magnitude and were directly correlated with changes in water temperature. The correlation between AVS and temperature likely was related both to changes in primary productivity and sediment microbial activity.

Toxicity of fluoranthene in sediment to marine amphipods: A test of the equilibrium partitioning approach to sediment quality criteria

AbstractThe toxicity of fluoranthene in sediment to the marine benthic amphipods, Rhepoxynius abronius (Barnard) and Corophium spinicorne (Stimpson) was determined in relation to the equilibrium partitioning approach to the development of sediment quality criteria. Toxicity tests were conducted with well‐sorted fine sands at three levels of organic carbon (OC), 0.18, 0.31 and 0.48%. Measured interstitial water concentrations of fluoranthene less than 50 μg/L were highly correlated with predictions based on the equilibrium partitioning model. LC50s based on bulk (total) fluoranthene concentrations increased significantly with increasing sediment OC. LC50s based on fluoranthene concentrations in interstitial water were not significantly different between 0.18 and 0.48% OC or between 0.31 and 0.48% OC, but the LC50 at 0.31% OC was significantly higher than that at 0.18% OC. The regression of sediment OC on bulk fluoranthene LC50 was linear, indicating that the concentration of fluoranthene in interstitial water was constant at equitoxic conditions, as predicted by the equilibrium partitioning model. The 10‐d LC50 of fluoranthene in interstitial water (23.8 μg/L) was intermediate between the U.S. Environmental Protection Agency's (U.S. EPA) acute (40 μg/L) and chronic (16 μg/L) water quality values for fluoranthene. Within the limitations of these experiments (i.e., one chemical, two species, sandy sediment with low carbon content), the results indicate that sediment quality criteria derived from the equilibrium partitioning model and water quality criteria would protect sensitive benthic invertebrates. The epibenthic, tube‐dwelling Corophium was less sensitive to test sediments than the infaunal, free‐burrowing Rhepoxynius, possibly because of different routes of exposure to fluoranthene. There was a close correspondence between estimates of sediment quality for fluoranthene based on distinctly different methodologies including equilibrium partitioning, apparent effects threshold, toxicity tests applied to experimentally spiked sediment and toxicity tests applied to field‐collected sediment.