Neurotoxicity of pesticides: a brief review.

Pesticides are substances widely used to control unwanted pests such as insects, weeds, fungi and rodents. Most pesticides are not highly selective, and are also toxic to nontarget species, including humans. A number of pesticides can cause neurotoxicity. Insecticides, which kill insects by targeting their nervous system, have neurotoxic effect in mammals as well. This family of chemicals comprises the organophosphates, the carbamates, the pyrethroids, the organochlorines, and other compounds. Insecticides interfere with chemical neurotransmission or ion channels, and usually cause reversible neurotoxic effects, that could nevertheless be lethal. Some herbicides and fungicides have also been shown to possess neurotoxic properties. The effects of pesticides on the nervous system may be involved in their acute toxicity, as in case of most insecticides, or may contribute to chronic neurodegenerative disorders, most notably Parkinson's disease. This brief review highlights some of the main neurotoxic pesticides, their effects, and mechanisms of action.