The neurotoxic potency of the average residues presented here is based on residues of organophosphate insecticides plus the carbamate compound, carbaryl. For most crops carbaryl contributed a very small portion of overall neurotoxic potency. Organophosphate and carbamate insecticides block the normal functioning of the enzyme acetylcholinesterase at the nerve endings. Severe organophosphate poisoning can lead to nausea, vomiting, muscle spasms, blurred vision, coma, and even death. Carbamate poisoning, which causes similar symptoms, is generally reversible within a 24 hour period.
Organophosphates are toxic for a longer period of time.
Exposure to residues of neurotoxic organophosphate insecticides in the diet may pose serious health risks to children. The actual number of children at risk is most likely much higher because their are at least 15 organophosphates in widespread use on at least 40 fruits and vegetables. These rules have never been enforced. Some of the most widely used organophosphate insecticides are chlorpyrifos, dimethoate, malathion, methamidaphos, and methyl parathion. Carbaryl is the most heavily used carbamate.