A weight‐of‐evidence approach for the integration of environmental “triad” data to assess ecological risk and biological vulnerability

Abstract

A new Expert Decision Support System (EDSS) that can integrate Triad data for assessing environmental risk and biological vulnerability at contaminated sites has been developed. Starting with ecosystem relevance, the EDSS assigns different weights to the results obtained from Triad disciplines. The following parameters have been employed: 1) chemical soil analyses (revealing the presence of potentially dangerous substances), 2) ecotoxicological bioassays (utilizing classical endpoints such as survival and reproduction rates), 3) biomarkers (showing sublethal pollutant effects), and 4) ecological parameters (assessing changes in community structure and functions). For each Triad discipline, the EDSS compares the data obtained at the studied field sites with reference values and calculates different 0-1 indexes (e.g., Chemical Risk Index, Ecotoxicological Risk Index, and Ecological Risk Index). The EDSS output consists of 3 indexes: 1) Environmental Risk index (EnvRI), quantifying the levels of biological damage at population-community level, 2) Biological Vulnerability Index (BVI), assessing the potential threats to biological equilibriums, and 3) Genotoxicity Index (GTI), screening genotoxicity effects. The EDSS has been applied in the integration of a battery of Triad data obtained during the European Union-funded Life Intervention in the Fraschetta Area (LINFA) project, which has been carried out in order to estimate the potential risk from soils of a highly anthropized area (Alessandria, Italy) mainly impacted by deposition of atmospheric pollutants. Results obtained during 4 seasonal sampling campaigns (2004-2005) show maximum values of EnvRI in sites A and B (characterized by industrial releases) and lower levels in site D (affected by vehicular traffic emissions). All 3 potentially polluted sites have shown high levels of BVI and GTI, suggesting a general change from reference conditions (site C).

Toxicity of diesel contaminated soils to the subantarctic earthworm Microscolex macquariensis

“…Such differences in standards among countries lead to questions regarding the most appropriate environmentally relevant remediation target. The most ecologically protective and relevant guidelines should incorporate thorough site-specific ecological risk assessments, encompassing chemical, toxicological, and ecological data, highlighting compounds that require remediation to pre-determined protective concentrations [5,6]. Using M. macquariensis as an indicator of soil quality, the endpoints developed in the present study suggests that soil SAB concentrations of between approximately 50 to 200 mg SAB/kg soil would be a sufficiently protective remediation target depending on soil type.…”

“…Nations operating in polar and subpolar regions regulate the management of contaminated sites through domestic guidelines and legislation. To assess the impact of contamination on an ecosystem fully, a weight of evidence approach to environmental risk assessment, which includes chemical analysis, ecotoxicological testing, and ecological assessment is recommended [5,6]. Toxicity tests using a suite of species from different trophic levels are therefore an important component of risk assessments.…”

Aquatic ecotoxicology: what has been accomplished and what lies ahead? An Eastern Canada historical perspective

“…For example, WOE studies can include toxicity testing on whole organisms, multiple biomarker measurements, and chemistry on water, sediment and tissue, as well as ecological parameters. 25 With continuing development in ecotoxicological research that led to increasing numbers of biomarkers, they have often been grouped into different categories based on the type of ecotoxicity information that they engender (Table 1) 21,[26][27][28][29][30][31][32][33][34][35][36][37][38][39] . Of notable interest are biomarkers that can intimate exposure to a specific class of chemicals.…”

Application of stress index in evaluating toxicological response of soil microbial community to contaminants in soils

“…The ratio to reference approach is commonly applied in ecological risk assessment. In this method, the risk of contamination is quantified by comparing the responses of organisms at ecotoxicological and ecological levels to those from a reference site, which was first suggested in application of biomarkers (Dagnino et al, 2008;Semenzin et al, 2008). During application of this method, it should be assumed that there is a reference site that has similar physical and chemical properties as the soils at the study sites.…”

“…Relative stress responses (RSR) are calculated by comparing the responses of microbial organisms exposed to contaminated soil with those exposed to the reference soil. The RSR is then compared with two threshold values (Th 1 and Th 2) (Dagnino et al, 2008). Th1 is the test result below which the impairment level for the tested endpoint can be regarded as negligible and/or caused by natural variability, while Th2 is the test results above which the impairment level for the tested endpoint is regarded to be no more significant (Semenzin et al, 2008).…”