Hazards from environmental contaminants have become a necessary part of life in industrial countries. In the past few decades, a number of 'new' problems have arisen (termiticide-treated premises, reentry into pesticide-treated fields, acid rain, aldicarb in ground water, dioxins in city environs, military use of dioxin-contaminated herbicides, accidents with PCB's and PBB's and other persistent chemicals, a large number of potentially hazardous chemicals in dump sites, and other problems which have caused public awareness of environmental contamination. These compounds are often found in small amounts (parts per billion), and the potential hazard has often been inadequately clarified. Although most industrial countries share the problem with the U.S., this latter country seems especially vulnerable due both to the sheer quantity of production and the lack of proper perspectives and management following World War II.