Organophosphorus compounds are widely used in agriculture and industry. Although the immediate and delayed effects of acute exposure have been well described, the clinical sequelae of chronic, low-dose exposure are less certain. This paper describes the case of a farmer who had been exposed to a variety of organophosphate pesticides over a 30-year period, and developed sensory ataxia, which has not previously been described. She was found to have an abnormal cholinesterase phenotype. Mechanisms of possible increased sensitivity to these compounds are discussed which may, in future, allow certain occupational groups to be screened.
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