Introduction and background

Abstract

This chapter identifies and critically reviews knowledge on the health effects of human exposure to selected chemical agents and physical factors in the ambient environment. Chemical contaminants can be air contaminants, water contaminants, or food contaminants. People can be exposed to chemicals in the environment in numerous ways. The chemicals can be inhaled, ingested, or taken up by and through the skin. Exposure is a key step in this continuum and a complex one. The concept of total human exposure, or exposome, has developed as essential to the appreciation of the nature and extent of environmental health hazards associated with ubiquitous chemicals at low levels. The chapter addresses the pathways and transport rates of toxic chemicals from environmental media to critical tissue sites as well as retention times at those sites. Exposure‐response relationships can be developed from human experience.