Pesticides These are the substances that are used to kill or block the reproductive processes of pests. These are basically synthetic toxic chemicals with ecological repercussions. Their accumulation in higher animals (through food chain) causes serious metabolic and physiological disorders. DDT, aldrin, dieldrin, organophosphates and carbamates are some examples of pesticides.
Herbicides These are weed killers, e.g., sodium chlorate and sodium arsenite . These are toxic to mammals. Some herbicides cause birth defects. Now a days triazines, better herbicides are used for the corn fields.