People living near a farm that uses pesticides are up to six times more likely to suffer from Parkinson's disease in later life.
Children are especially vulnerable, and face the highest risk of developing the degenerative disease, although anybody under the age of 60 could face a risk that is between four and six times greater than for someone living in an urban area.
The findings have been made by researchers at UCLA School of Public Health who studied the health of residents living in California's Central Valley, a major crop-growing region.
The pesticides maneb and paraquat are commonly used on farms in the area, and the researchers reckon anyone living within 500 metres of treated land face an increased risk of developing Parkinson's. The overall increased risk was 75 per cent, depending on the number of years of exposure and proximity to farmland.
(Source: American Journal of Epidemiology, 2009; 169: 919-26).