Superfund Research Program
There are approximately 40 organophosphate pesticides, and as a group they account for approximately half of the insecticide use in the United States. The majority of organophosphate use is on food crops, but they are often used in and around the home control termites, lawn insects, ants, cockroaches, fleas, ticks, and mosquitoes. Examples of organophosphate pesticides include chlorpyrifos, azinphos methyl, methyl parathion, and phosmet.
Organophosphates kill insects and other animals by impacting the function of the central and peripheral nervous system. They inhibit the activity of acetylcholinesterase (AChE), an enzyme which breaks down the neurotransmitter acetylcholine. The resulting interference with nerve transmissions is of such a magnitude that it actually kills insects. In overdoses, organophosphates can also kill people and pets. Of greater and increasing concern however, are studies in animals show that even a single, low-level exposure to certain organophosphates, during particular times of early brain development, can cause permanent changes in brain chemistry as well as changes in behavior, like hyperactivity. Research suggests that early childhood exposures pesticides, which can go undetected because of the lack of overt symptoms, to certain organophosphates can lead to lasting effects on learning, attention, and behavior -- just as were seen with another environmental neurotoxin, lead.
Use the search tools below to find additional information about SRP-funded research on organophosphates.