ESTERASE INHIBITORS AS PESTICIDES.

Thirty years of testing has yielded over 120 esterase inhibitors in current use for pest control. Several hundred million pounds of these organophosphates and carbamates are employed each year as insecticides and acaricides and, to a much lesser extent, as anthelmintic agents, nematocides, and herbicides. Systemics or chemotherapeutic agents for control of insect pests of plants and animals first became practical with the organophosphates. Compounds of lower mammalian toxicity and other favorable biological properties continue to appear and displace established compounds and broaden the use areas. Problems of resistance and residues in certain areas of insect control by chlorinated hydrocarbons will result in a further shift to esterase-inhibitors for pest control. Interpretation of the potential hazards of pesticides to man is dependent on the availability of fundamental information on their modes of action combined with use experience; this knowledge is available for the organophosphates and carbamates that act as acetylcholinesterase inhibitors.