RESUMEN
In the last two years, the environmental theory on the aetiology of Parkinson disease has acquired new data. From an experimental point of view, a new model of parkinsonism induced by rotenone, a diffuse insecticide, has been proposed, and in vitro studies have provided proof that several pesticides stimulate the formation of alpha-synuclein fibrils (one of the principal constituents of Lewy bodies). Moreover, a meta-analysis of all case-control studies so far performed showed a positive, statistically significant association between pesticide exposure and PD. In this context, we are performing a cohort study on 5575 licensed pesticide users in the province of Viterbo. After 27 years of follow-up, 4788 subjects are still alive. The aim of this study is to measure the prevalence of Parkinson's disease in a large group of workers with theoretically increased risk.