Ecological risk assessment data acquisition

As mentioned before, the ecological risk assessment is characterized by a problem formulation process, analysis containing characterizations of exposure and effects, and a risk characterization process. Several outlying boxes serve to emphasize the importance of discussions during the problem formulation process between the risk assessor and the risk manager, and the critical nature of the acquisition of new data, verification of the risk assessment, and monitoring. The next few sections detail each aspect of this framework. 

Schematic of the framework for ecological risk assessment (U.S. EPA1992). Especially important is the interaction between exposure and hazard and the inclusion of a data acquisition, verification, and monitoring component. Multivariate analyses will have a major impact on the selection or assessment and measurement endpoints and will play a major role in the data acquisition, verification, and monitoring phase.

Other important companion activities to ecological risk assessment include data acquisition and verification and monitoring studies. New data are frequently required to conduct analyses that are performed during the risk assessment. Data from verification studies can be used to validate the predictions of a specific risk assessment as well as to evaluate the usefulness of... 

The interaction between data acquisition and ecological risk assessment is also shown in Figure 1. In this report, a distinction is made between data acquisition (which is outside of the risk assessment process) and data analysis (which is an integral part of an ecological risk assessment). In the problem formulation and analysis phases, the risk assessor may identify the need for additional data to complete an analysis. At this point, the risk assessment stops until the necessary data are acquired. When a need for additional data... 

Suter et al. 1993 Society of Environmental Toxicology and Chemistry [SETAC] 1994 European Union 1997 Ecological Committee on FIFRA Risk Assessment Methods [ECOFRAM] 1999 Campbell et al. 1999). The initial use of conservative assessment criteria (i.e., err on the side of caution) allows substances that do not present a risk to be eliminated from the risk assessment process early, thus allowing the focus of resources and expertise to be shifted to potentially more problematic substances or situations. As one ascends through the tiers, the estimates of exposure and effects become more realistic with the acquisition of more accurate and/or representative data, and uncertainty in the extrapolation of effects is thus reduced or at least better characterized. Likewise, the methods of extrapolation may become more sophisticated as one ascends through the tiers (Figure 1.2). 

The site assessment must provide sufficient information to identify relevant health and ecological concerns and assess the need for remedial action. To support a risk-based site evaluation, these data must be sufficient to construct a site conceptual exposure model characterizing affected environmental media (i.e., soil, groundwater, surface water, and sediment), applicable exposure pathways and receptors, and potential contaminant transport mechanisms. General guidelines regarding key data requirements and data acquisition procedures are summarized below. 

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