The report summarizes research in which DDT has been studied in both heavily exposed workers and in groups of volunteers given oral dosages of the pesticide. The population is exposed to DDT from many sources, such as food, household uses, dust, and air. The total exposure is not known nor is the relative contribution from the various sources. The exposure from food has been, and continues to be, carefully investigated. The calculated intake of dietary DDT has been quite small with an average of slightly less than 0.2 mg per man per day even when the use of DDT was at its peak. Present dietary levels based on total diet surveys, however, appear to be approximately 0.02 mg per man per day, or about 1/10 of the earlier value. These surveys contain the kinds and quantities of foods consumed by the 16- to 19-year-old group in our population and represents almost twice the average dietary intake of the average individual.