Assessing the impact of chemical pollution on benthic invertebrates from three different European rivers using a weight-of-evidence approach (original) (raw)
Toward an Integrated Assessment of the Ecological and Chemical Status of European River Basins
Integrated Environmental Assessment and Management, 2009
This is 1 of 12 papers prepared by participants attending the workshop ''Risk Assessment in European River Basins-State of the Art and Future Challenges'' held in Liepzig, Germany on 12-14 November 2007. The meeting was organized within the framework of the European Commission's Coordination Action RISKBASE program. The objective of RISKBASE is to review and synthesize the outcome of European Commission FP4-FP6 projects, and other major initiatives, related to integrated risk assessment-based management of the water/ sediment/soil environment at the river basin scale.
2011
Evaluation of chemical bioavailability and onset of biological alterations is fundamental to assess the hazard of environmental pollutants, particularly when associated to sediments which need to be removed. In the present work, five sediment samples were collected from the Venice Lagoon and data from sediment chemistry were integrated with those of bioaccumulation of chemicals in European eel (Anguilla anguilla) exposed under laboratory conditions, responses of a wide battery of biomarkers, and standardized ecotoxicological bioassays. The overall results were elaborated within a recently developed, softwareassisted weight of evidence (WOE) model which provides synthetic indices for each of considered line of evidence (LOE), before a general evaluation of sediment hazard. Levels of chemicals in sediments were not particularly elevated when compared to sediment quality guidelines of Venice Protocol. On the other hand, bioavailability was evident in some samples for Cd, Cu, Zn and, especially, polycyclic aromatic hydrocarbons. The ecotoxicological approach provided further evidence on the biological and potentially harmful effects due to released contaminants, and oxidative-mediated responses appeared of primary importance in modulating sublethal responses and the onset of cellular alterations. Biomarkers variations were sensitive, and more evident variations included significant changes of cytochrome P450 biotransformation pathway, antioxidant responses, onset of oxidative damages, lysosomal membrane stability and genotoxic effects. The results obtained from the battery of bioassays indicated that responses measured at organism level were in general accordance but less marked compared to the onset of sublethal changes measured through biomarkers. Overall this study revealed differences when comparing evaluations obtained from different LOEs, confirming the importance of considering synergistic effects between chemicals in complex mixtures. Compared to a qualitative pass-fail approach toward normative values, the proposed WOE model allowed a quantitative characterization of sediment hazard and a better discrimination of on the basis of various types of chemical and biological data.
Archives of Environmental Contamination and Toxicology, 2007
A Sediment Quality Triad (SQT) study consisting of chemical characterization in sediment, sediment toxicity and bioaccumulation testing, and benthic community assessments was performed in the Lower Hackensack River, New Jersey. Chemistry data in sediment and porewater were evaluated based on the equilibrium partitioning approach and other published information to investigate the potential for chemical effects on benthic organisms and communities. Relationships were supported by laboratory toxicity and bioaccumulation experiments to characterize chemical effects and bioavailability. Benthic community results were evaluated using a regional, multimetric benthic index of biotic integrity and four heterogeneity indices. Evidence of slight benthic community impairment was observed in five of nine sediment sample stations. Severe lethal toxicity to amphipods (Leptocheirus plumulosus) occurred in four of these five stations. Although elevated total chromium concentrations in sediment (as high as 1900 mg/kg) were the rationale for conducting the investigation, toxicity was strongly associated with concentrations of polycyclic aromatic hydrocarbons (PAHs) rather than total chromium. PAH toxic units (RPAH TU) in sediment and RPAH concentrations in laboratory organisms from the bioaccumulation experiment showed a clear dose-response relationship with toxicity, with 0% survival observed in sediments in which RPAH TU > 1-2 and RPAH concentrations in Macoma nasuta were >2 lmol/g, lipid weight. Metals detected in sediment and porewater, with the possible exception of copper, did not correlate with either toxicity or levels in tissue, likely because acid-volatile sulfide levels exceeded concentrations of simultaneous extracted metals at all sample locations. The study reinforces the value of using multiple lines of evidence approaches such as the SQT and the importance of augmenting chemical and biological analyses with modeling and/or other approaches to evaluate chemical bioavailability and toxicity of sediments.
Chemosphere, 2010
Biotic indices based on macro-invertebrates and diatoms are frequently used to diagnose ecological quality in watercourses, but few published works have assessed their effectiveness as biomonitors of the concentration of micropollutants. A biological survey performed at 188 sites in the basin of the River Duero in north-western Spain. Nineteen diatom and six macro-invertebrate indices were calculated and compared with the concentrations of 37 different toxicants by means of a correlation analysis.
Nematode species at risk — A metric to assess pollution in soft sediments of freshwaters
Environment International, 2011
Soft sediments are often highly polluted as many of the toxic chemicals introduced into surface waters bind to settling particles. The resulting accumulation of pollutants in the sediments poses a risk for benthic communities. However, pollution induced changes in benthic communities have been difficult to determine when using macro-invertebrates as bioindicators, as these organisms are often absent in soft sediment. The present study therefore examined the ability of meiofaunal organisms, specifically, nematodes, to assess the ecological status of soft sediments. Over a 9-year period, nematode communities present in sediments collected from large rivers and lake Constance in Germany were studied. These sediments showed a large range of physico-chemical properties and anthropogenic contamination. After the degree of metal and organic contamination was translated into ecotoxicologically more relevant toxic units (TUs), multivariate methods were used to classify nematode taxa in species at risk (NemaSPEAR) or not at risk (NemaSPE(not)AR). This approach clearly distinguished the influence of sediment texture from that of the toxic potential of the samples and thus allowed classification of the nematode species according to their sensitivity to or tolerance of toxic stress. Two indices, expressing the proportion of species at risk within a sample (NemaSPEAR[%](metal), NemaSPEAR[%](organic)), were calculated from independent data sets obtained in field and experimental studies and showed good correlations with the toxic potential (field data) or chemical concentrations (microcosm data). NemaSPEAR[%] indices for metal and organic pollution were therefore judged to be suitable for assessing the impact of chemical contamination of freshwater soft sediments.
Freshwater Biology, 2015
1. Detrimental impacts of excessive fine-grained sediment inputs to streams and rivers are well established. What is less well understood is the susceptibility of different elements of the freshwater biota to such perturbations and how such knowledge of their susceptibility could aid in identifying where excessive fine-grained sediment is impairing ecological condition. 2. Following the collection of biological and sediment data from 179 streams across England and Wales, representative of a range of river types over a gradient of fine sediment loading, objective statistical approaches were applied to establish relationships between the macroinvertebrate assemblage and fine-grained sediment inputs to river channels. 3. Having factored out that portion of the biological variation associated with natural environmental gradients, a model comprising mass of organic sediment in erosional areas of the stream bed (predominantly associated with the first axis of the partial canonical correspondence analysis (pCCA)), and mass of fine-grained sediment in the surface drape of depositional areas and % organic content in erosional areas (associated with the second axis of the pCCA) as explanatory variables best accounted for the residual variation in the macroinvertebrate assemblage. 4. The relative position of taxa along both axes of the pCCA, provided a ranking of taxa in relation to the two gradients of fine-grained sediment and provided the basis for a new empirically-derived diagnostic index for fine-grained sediment stress in rivers. Two sub-indices were derived to capture the assemblage responses to both the gradient of organic sediment in erosional areas and the gradient of total fines in depositional areas. The two sub-indices were then combined to derive the new combined fine sediment index (CoFSI sp). 5. The index was tested on an independent test dataset (comprising 127 samples from 83 sites) and was found to provide a robust indication of benthic fine-grained sediment conditions (Spearman rank correlations ρ =-0.519 to-0.703). The strength of correlation with the total fine-grained sediment gradient was always greater than that for other routinely used indices, confirming that CoFSI sp offered additional explanatory power when assessing this stressor of aquatic environments.
Water Science & Technology, 2007
Benthic invertebrate assessments can be used to gauge the impact of urban wet-weather flows in receiving waters. Experiences from Cemagref in France have shown that standardized benthic indices (e.g. Oligochaete Index of Sediment Bioindication -IOBS) can be used to reliably determine the ecological status of urban streams and can be incorporated into the new European Water Framework Directive. The Canadian studies on streams and stormwater ponds using chemical analyses, benthic toxicity testing and benthic invertebrate community structure (i.e. the sediment quality triad) comparisons have shown that toxicity was more likely to occur in ponds at sites with higher concentrations of heavy metals and heavier polycyclic aromatic hydrocarbons, and at greater water depths, where fine sediments from urban runoff accumulated. A more comprehensive evaluation of wet-weather flow impacts could be obtained by combining approaches from both countries.
Environmental Toxicology and Chemistry, 2019
Sediment toxicity is usually assessed by conducting laboratory bioassays on thoroughly homogenized, field collected, sediment samples. While it is generally held that these bioassays provide a conservative assessment of the potential for environmental impact there are few studies comparing results of laboratory sediment bioassays to actual measures of benthic community health in exposed field populations. To help inform an understanding of the relative efficacy of laboratory based bioassays in predicting potential impacts in exposed field populations, a laboratory to field comparison study was conducted. Laboratory bioassays included standard 10-day acute toxicity tests measuring survival in four species of estuarine/marine amphipods (e.g., Eohaustorius estuarius, Ampelisca abdita, Rhepoxinius abronius, and Leptocheirus plumulosus) and two longer-term, 28-day sublethal tests with a marine polychaete, Neanthes arenaceodentata (survival and growth) and the amphipod L. plumulosus (survival, growth, and reproduction). A highly contaminated and toxic sediment was mixed with a cleaner sediment of similar grainsize to produce a series of diluted contaminated sediment treatments (e.g., 0%, 6%, 12%, 25%, and 50%). Sediment treatments were placed in containers and deployed in the field. At specified intervals (e.g., at time of deployment and 9 and 12 months post-deployment) containers were retrieved from the field and analyzed for sediment chemistry, infaunal community composition and toxicity. Laboratory toxicity endpoints were compared to measures of benthic community health to evaluate the ability of the toxicity tests to accurately predict benthic impacts. Results of these comparisons indicate that the laboratory tests evaluated provide conservative estimates of potential benthic community impacts with both acute This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as
Water, 2020
The Water Framework Directive (WFD) aims to monitor continental water bodies in Europe to achieve good ecological status. Indexes based on biological quality elements (BQEs), ecotoxicological tests, and chemical characterizations are commonly used with standardized protocols to assess sediment quality and the associated risks. Here, we compare the results of quality assessment of benthic macroinvertebrates as BQEs as required by the WFD with the results of ecotoxicological tests and assessment of selected persistent organic pollutants (POPs) in sediments of the same eight water bodies in Italy. The aim was to verify if the assessment of quality through macroinvertebrates through POPs analyses and ecotoxicological tools can yield comparable, overlapping, or complementary results. We used the Benthic Quality Index (BQIES) for macroinvertebrates (two different applications), legacy POPs (dichloro-diphenyl-trichloroethane and metabolites (DDTs) and polychlorinated-biphenyls (PCBs)), and...
Responses of benthic invertebrates to combined toxicant and food input in floodplain lake sediments
Environmental Toxicology and Chemistry, 2002
Benthic communities in floodplain lake ecosystems are often exposed to varying levels of both food and toxicants. Inhibition through toxicants of sensitive species and stimulation through increased amounts of food of opportunistic species have been observed in separate studies. The aim of this study was therefore to assess the responses of benthic invertebrates to combined food and contamination input. Hence, seven floodplain lakes located along the River Waal, The Netherlands, with different levels of food (being either phytoplankton or macrophyte dominated) and toxicants were selected. The responses of the sensitive mayfly Ephoron virgo and the opportunistic midge Chironomus riparius to these sediments were assessed in 10-d growth bioassays with both species and a 28-d emergence experiment with C. riparius. A decrease in both survival and growth of E. virgo was observed with increasing contaminant levels. In contrast, C. riparius responded to the food quantity and quality in the sediments in spite of the toxicants present. Therefore, we conclude that the midge C. riparius is not a suitable test organism for the assessment of sediment toxicity. Alternatively, it proved to be an appropriate test organism to determine the nutritional value of sediments. The mayfly E. virgo turned out to be a much more appropriate test organism for sediment toxicity bioassays because it responds to the toxicant levels in the sediments rather than to the nutritional value. Our results demonstrate that the trophic state of an ecosystem (macrophyte or plankton dominated) influences the ecological risk of toxicants to benthic invertebrates in a species-specific way. It is concluded that not the toxicant load but the combination of food and contaminants determines the persistence of benthic invertebrates and therewith the benthic invertebrate composition in complexly polluted ecosystems.