ABSTRACT
Millions of yards of soil throughout the United States have been contaminated with numerous types of liquid and solid wastes containing metals, radioactive materials, gasoline, solvents, used oils, and sludges. The potential environmental hazards due to contamination of runoff water and pollution of groundwater, as well as the possible adverse effects on biota, fish, and wildlife, have been studied for a number of years. Occupational exposure will normally be limited to those who are involved in the remediation of hazardous waste sites. Post hoc estimates of exposure can also be valuable in interpreting and conducting epidemiological studies. Contaminated soil can pose not only a direct hazard to humans but also indirect hazards. The exposure estimation procedure is perhaps the most important aspect of risk assessments of sites having contaminated soil. An important distinction that is often blurred is the difference between the ingestion of very small quantities of dirt due to mouthing tendencies and the disease known as pica.
