Pesticides and Toxic Substances in the Environment

Abstract

Uses of pesticides have been regulated under the authority of the Federal Insecticide, Fungicide, and Rodenticide Act since 1948. In 1972, the Act was amended to include particular emphasis on the protection of public health and the environment. One result of these amendments has been an increased awareness of monitoring activities. Monitoring data are critical factors in an exposure assessment and thus are important elements in quantitative evaluations of hazard and risk. Monitoring is a general term used to describe a wide variety of efforts. Basically, monitoring is an activity in which specimens of selected human and environmental components are sampled and then analyzed for evidence of chemical residues indicative of potential human, animal, or plant exposure. Human and environmental monitoring programs for pesticides and selected toxic chemicals have been conducted for over 15 years. The initial ambient monitoring systems were designed to determine average concentrations of pesticides and related chemicals in human and environmental media on a nation-wide basis and determine changes in these concentrations over time. The results of these surveys showed that almost all of the general human population and various environmental components contained low concentrations of organochlorine pesticides. After the Environmental Protection Agency restricted many uses of certain chlorinated pesticides, the organophosphorous and carbamate insecticides which replaced them and some other commonly used pesticides were not as easily monitored by ambient surveys. Special monitoring studies had to be done more frequently to produce data on these compounds which were not as persistent or accumulative in the environment.