ENVIRONMENTAL HEALTH IMPACTS FROM NATURAL MATERIALS: AN EPA PERSPECTIVE

The vast proportion of chemicals that humans are exposed to on a day-to-day basis occur naturally in the environment. There is widespread public belief that these substances are safe and that synthetic chemicals that are in the marketplace are toxic while, in fact, many chemicals are toxic at some dose, regardless of their origin. In addition to background exposures to these substances, humans are exposed to naturally occurring chemicals through manufacturing processes and disposal practices that may release them to the air, soil and water. From an EPA perspective, assessing potential human health risks associated with naturally occurring substances presents particular challenges. Ongoing EPA research and analysis related to the human health effects of such naturally occurring substances as lead, asbestos, arsenic, and polycylic aromatic compounds will be discussed along with some of the challenges associated with regulating this special class of substances.