Environmental Health Risk Assessment

Abstract

AbstractQuantitative health risk assessment is a tool for making predictions about the impact of substances in the environment on health. Despite the use of scientific principles and a reliance on the most appropriate data from the scientific literature, risk assessment, in the strict sense of the word, is not, by itself, a science. Two different forms of quantitative risk assessment are practiced. One form can be referred to assafety assessment, which seeks to identify the largest level of exposure or dose that can be reasonably expected to be without adverse effect. The other form seeks to quantify the risk associated with any exposure or dose of an environmental agent. In the United States, this form of risk assessment is generally applied to carcinogens. The classical structure of formal environmental health risk assessments comprises of four interdependent steps: hazard identification; dose–response assessment; exposure assessment; and risk characterization. Recent advances in conducting environmental health risk assessments include the use of the benchmark dose approach in lieu of the no observed adverse effect level (NOAEL)/lowest observed adverse effect level (LOAEL) determination, the use of probabilistic analysis in place of single value estimates for risk assessment variables, and progress toward harmonization of cancer and noncancer endpoints.