Protocol for the Derivation of Environmental and Human ... - CCME

Section 1
Derivation of Environmental Soil Quality Guidelines
It is important to understand what is meant by ecological effects when deriving environmental soil quality
guidelines. A wide range of effects can be considered when examining various components of a
terrestrial ecosystem. These include both abiotic and biotic factors which influence ecosystem structure
and function. Assessing the magnitude of potential effects of all of these factors usually requires an
ecological risk assessment. This protocol focuses on the effects of chemical stressors on the biotic
component of a terrestrial ecosystem. Specifically, the potential for adverse effects to occur from
exposures to soil-based contaminants at point-of-contact or by indirect means (i.e., food chain transfer).
Adverse effects data may come in a variety of forms, ranging from data collected in the field (e.g.,
mesocosm studies) to single species tests performed in the laboratory (i.e., using bioassays). Specific
land uses are studied and guidelines based on the availability of terrestrial toxicity information are
developed in this protocol. As a result, the assessment of specific chemical stressors will be narrower in
scope than other media.
The following sections examine topics related to the "initial staging" of guidelines development and
provide a detailed description of the guidelines derivation process. These topics include narrative and
illustrative descriptions of the level of ecological protection envisioned for guidelines, relevant endpoints,
availability of soil toxicity data for guidelines derivation, and the formulation of exposure scenarios for
contaminated soil. Potential exposure pathways, receptor arrays, and exposure scenarios for individual
land use categories are also examined. Based on information from the initial staging, the process for
deriving soil quality guidelines is then presented.
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