Poisoning by pesticides

Abstract

Around 150,000 people die each year from pesticide poisoning. Most deaths result from self-poisoning by ingestion, rather than occupational or accidental exposures, which are typically topical or inhalational. Severe pesticide poisoning is more common in rural lower- and middle-income countries where pesticides are widely used in smallholder agricultural practice and therefore freely available. Significant acute poisoning is much less common in industrialized countries; here the long-term effects of low-dose chronic exposure most concern the population. Poisoning from organophosphorus and carbamate insecticides causes most severe cases and deaths worldwide, although numbers are falling as the most highly toxic compounds are withdrawn from agricultural practice. Severe organophosphorus poisoning requires urgent resuscitation and administration of oxygen, atropine and oximes. Paraquat and aluminium phosphide are major problems in some countries, with case fatality usually >50% and no effective treatments. Newer pesticides that have become widely used over the last 30 years, for example neonicotinoid and phenylpyrazole insecticides, are more selective in their toxicity to pests, resulting in far less acute human toxicity and few deaths. Toxicity can result from solvents rather than the pesticide's active ingredient. Acute poisoning with newer pesticides usually requires only careful supportive care.