Use Patterns

Insecticides as a class of pesticides constitute about one-quarter of total pesticides (approximately a billion pounds per year) used in the United States. By far the largest volume of pesticides used is herbicides (620 million pounds), followed by insecticides (247 million pounds) and fungicides (131 million pounds) (all 1993). Approximately 75% of all pesticides used in 1993 were for the control of agricultural pests. Other uses are for pests found in the home (including gardens), industry, commerce, and public and veterinary health. The top 17 insecticides (used in 1993) were (1) chlorpyrifos, (2) terbufos, (3) methyl parathion, (4) carbofuran, (5) carbaryl, (6) phorate, (7) cryolite, (8) aldicarb, (9) propargite, (10) acephate, (11) malathion, (12) fenofos, (13) methomyl, (14) dimethoate, (15) azinphos-methyl, (16) ethyl parathion, and (17) profenfos. Most of these are organophosphates (1-3, 6, 10-12, 14-17) or carbamates (4, 5, 8, 13), but propargite is a sulfite ascaricide and cryolite (sodium fluoroaluminate, Na3ÁlF6) is a naturally occurring inorganic fluoride compound. Of these, the use of methyl parathion (3) and ethyl parathion (16) has been phased out. Among organochlorine insecticides, most of which have been eliminated, the only ones remaining are endosulfan (19th) and dicofol (22nd). The most popular pyrethroid is permethrin (25th, approximately 1,000,000 pounds) followed by cypermethrin (225,000 pounds) and fenvalerate (66,000 pounds). Pyrethroids are used in much lower quantities than organophosphates and carbamates mainly because the former compounds are much more powerful than the latter, and therefore only small amounts of pyrethroids per hectare are needed to control insect pests.

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