Health risk assessment is a systematic approach for characterizing human exposures in and out of the workplace. It has been relied upon for over 40 years as the basis of decision making for nearly all chemicals. Risk assessments can be used in a variety of contexts, including evaluating exposure to chemicals associated with consumer products, occupational settings, or specific contaminated sites. These assessments are the foundation for decision-making in the corporate setting, regulatory rule-making, and toxic-tort litigation.