Multiple agents and stressors can interact in a given community to adversely affect human and ecological conditions. A cumulative risk assessment (CRA) analyzes, characterizes, and potentially quantifies the effects from multiple stressors, which include chemical agents (for example, benzene) as well as biological (for example, vector-borne illness), physical (for example, housing characteristics), and psychological (for example, socioeconomic) ones. The distinguishing feature of a CRA is an analysis of combined effects and interactions.