Tri-Service Remedial Project Manager's Guide for Ecological Risk ...

iomarkers may be induced by many man-made or natural stressors. When biomarkers areused, other indicators should be utilized to assure that the stressor causes the effects inquestion.Biomonitoring: 1 Use of living organisms as “sensors” to detect changes in environmentalconditions that might threaten living organisms in the environment.Body Burden: 3 The amount of a substance that has accumulated in the tissue of an exposedorganism, usually expressed as the concentration of the substance in a particular organ or in thewhole organism.Characterization of Ecological Effects: 1 A portion of the analysis phase of ecological riskassessment that evaluates the ability of a stressor to cause adverse effects under a particular setof circumstances.Characterization of Exposure: 1 A portion of the analysis phase of ecological risk assessmentthat evaluates the interaction of the stressor with one or more ecological components. Exposurecan be expressed as co-occurrence, or contact depending on the stressor and the ecologicalcomponent involved.Chemical (Contaminant, Constituent) of Potential Ecological Concern (COPEC): 1 Asubstance detected at a hazardous waste site that has the potential to affect ecological receptorsadversely due to its concentration, distribution, and mode of toxicity.Chronic: 1,2 Involving a stimulus or response that continues for a long time; often from severalweeks to years, depending on the reproductive life cycle of the species (conventionally includesat least a tenth of the life span of a species). It can be used to define either the exposure or aneffect. Chronic exposures typically induce a biological response of relatively slow progress andlong duration.Chronic Response: 1 The response of (or effect on) an organism to a chemical that is notimmediately or directly lethal to the organism, but can affect long term health or survival of anorganism. Example: Population decline of birds due to chronic exposure to DDT.Chronic Toxicity Test: 3 A toxicity test that spans a significant portion of the life cycle of the testorganism (e.g., 10% or more) and examines effects on such parameters as metabolism, growth,reproduction, and survival.Community: 1,4 An assemblage of populations of different species within a specified location andtime. It is a broad term that may be used to designate natural assemblages of different sizes(e.g., organisms inhabiting a rotting log, organisms inhabiting a vast forest or an ocean).Concentration: 1 The relative amount of a substance in an environmental medium, expressed byrelative mass (e.g. mg/kg), volume (ml/L), or number of units (e.g., parts per million (ppm)).Concentration-Response Curve: 1 A curve describing the relationship between concentrationand percent of the test population responding. Example: soil concentration of a contaminantversus percent earthworm mortality.Key Terms - 2