Toxicology: The Basic Science of Poisons
PESTAB. Sources of chemicals in the environment are discussed. The agricultural use of chemicals results in contamination of soil and water. Domestic and urban use and disposal of pesticides also contributes to environmental contamination. The transport, disposition and mobility of chemicals in the environment are also considered. Factors which interact to determine the movement and fate of chemicals in the environment include their water solubility, soil adsorption characteristics, vaporization, partitioning, bioaccumulation, degradation processes, and chemodynamics. A discussion of the major classes of pesticides is presented; they are grouped as persistent, moderately persistent, or non-persistent. The persistent pesticides include chlorinated hydrocarbon insecticides and cationic herbicides (paraquat and diquat). Triazine herbicides, phenylurea herbicides and substituted dinitroanilines are considered to be moderately persistent. Nonpersistent pesticides include phenoxy acid herbicides, phenylcarbamate and carbanilate herbicides, ethylenebisdithiocarbamate fungicides, and organophosphorus and carbamate insecticides.