In EPA ecological risk assessment, Phase 2 is characterized by which activity?

• A. Analysis: determining what plants and animals are exposed and to what degree
• B. Problem formulation: gathering information to identify at-risk species
• C. Risk characterization: describing risks
• D. Post-assessment monitoring: evaluating after actions

Answer: (A)

Phase II centers on exposure analysis, determining what plants and animals are exposed and to what degree. This stage involves estimating the amount and duration of the stressor that different organisms encounter, considering exposure pathways and environmental concentrations, so that those exposure estimates can feed into subsequent risk calculations. The problem formulation phase that precedes this focuses on identifying at-risk species and endpoints, while the risk characterization phase that follows combines exposure with toxic effects to describe the overall risk. Post-assessment monitoring happens after actions are implemented to evaluate effectiveness. So the activity described—figuring out who is exposed and how much exposure they have—best fits Phase II.