A review of selected herbicides and their toxicities.

Since 2500 BC man has strived to develop methods of orderly pest control (1). These methods included prayer, physical labor, mechanical devices and chemicals. Through chemistry many new pesticides have been developed. Pesticides are "chemicals used to kill a species or a group of species that causes trouble, annoyance or destruction" (2) and include insecticides, rodenticides, fungicides and herbicides. This review focuses on the fastest growing group of pest control agents agents--herbicides. Arsenicals, chlorates, chlorophenoxy acids, biprydyl and substituted phenols are discussed as to their physical and chemical properties, sources, environmental fates, absorption/distribution/elimination, modes of action, toxic effects and recommended treatments.