Environmental risk assessment

Abstract

Environmental risk assessment is the process of evaluating the likelihood that adverse human health and ecological effects may occur or are occurring as a result of exposure to one or more agents. At contaminated sites, environmental risk assessment estimates risks of effects if no remedial action is taken and if each of the proposed alternatives were implemented. The purpose is to provide relevant and useful information to inform the remedial decision. The environmental risk assessment process begins with a planning phase that defines the scope and goals or the assessment. Next an analytical phase estimates exposure levels and exposure-response relationships for the contaminants of concern and the endpoint entities. Then a synthesis phase brings the analytical results together to estimate risks and associated uncertainties. The risks must then be communicated to the decision makers and stakeholders in a useful form. If a decision analysis is used to support the decision process, the risk assessment results should provide the needed input. Environmental risk assessments may be simple comparisons of point estimates of exposure to toxicological threshold values (e.g., no observed adverse effect levels). At the other extreme, they may include spatial analysis, probabilistic modeling, weighing of evidence, and other advanced techniques. Decision support systems may make environmental risk assessments quicker, easier, and more consistent and provide access to advanced analytical techniques. © 2009 Springer Science+Business Media, LLC.