Concentration: Area Curve Models For Evaluating Exposure and Risks to Terrestrial Receptors. C. Menzie and J. Freshman, Menzie-Cura & Associates, Inc., One Courthouse Lane, Suite Two, Chelmsford, MA 01824
Two exposure models have been developed to assess the potential for individual and population level effects for terrestrial wildlife exposed to contaminants in soils. The models incorporate information on the concentrations and spatial distributions of the chemicals as well as the foraging and movement of receptors. The models assume exposure is due to ingestion of contaminated food, such as soil invertebrates, that have accumulated chemicals from the soil. From this, the models compare chemical exposures to a variety of measurement endpoints. The Moving Average Soil concentration (MASC) exposure model is used to evaluate effects on individuals or groups on individuals who may be exposed to more contaminated locations. The Multiple Step (MUST) exposure model assesses exposure to fractions of the population and explicitly considers mosaic patterns in the distribution of contaminants together with patterns in the distributions of foraging activities. The models can be used in an exploratory way to reveal spatial scales of contamination, foraging areas, and contaminant levels that pose risks to individuals or populations.