[Environmental factors in the etiology of Parkinson's disease].

We examined the role of the environment in the development of Parkinson's disease (PD). A group of 42 parkinsonians have been compared with a group of 84 matched controls. The epidemiological study (1987-1989) covered the territory of the Community Health Department of Valleyfield, in southern Quebec (Canada). Odds ratio adjusted for age and sex were calculated for seven environmental factors. A decreased risk for PD was associated with residence in rural areas (OR: 0.31; p less than or equal to 0.05) and residence near industry or mining (OR: 0.15; p less than or equal to 0.05). An increased risk for PD seems to be associated with occupational exposure to the three metals Mn, Fe and Al (OR: 2.28; p = 0.07) especially when the duration of exposure is longer than 30 years (OR: 13.64; p less than or equal to 0.05). Other environmental factors not found to be associated with PD were: pesticides manipulation, farm work, industrial work and well water consumption.