All about exposure assessments, according to the EPA
Exposure refers to a measurable contact of an agent with a target or receptor for a specific duration of time. In the broadest terms, agents can be biological, physical, chemical, social, or psychological, and can produce both adverse and beneficial impacts to the target.
EPA has historically focused on minimizing negative impacts, but in a sustainability context assessing exposures that result in positive impacts is also relevant to evaluating tradeoffs. For human exposures, receptors can be individuals, populations, subpopulations, or life-stages of interest. For ecological systems, receptors can be individuals, populations, species communities, or ecosystems that include both wildlife and vegetation. For exposure to occur, the agent and the receptor must intersect in both space and time.