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Maps connect agro-chemicals to Parkinson's disease

It is never easy to tell precisely how agro-chemicals and their combinations harm people. The data required—pesticide names, amounts applied, level of exposure, geography, to start with—makes it tedious and limits accuracy.

Researchers from University of California in Berkley, usa, used gis (geographic information system), superimposed land-use maps and pesticide-use data using software, and estimated human exposure to pesticides in California's Central Valley. They also interviewed residents between 1998 and 2007.

Their conclusion: a combination of Paraquet, a widely used herbicide, and the fungicide Maneb can trigger degeneration of the central nervous system in people, leading to Parkinson's disease. Previous studies have shown similar effects of the two pesticides on animals.

The researchers interviewed 368 residents living within 500 metres of farms between 1974 and 1999. They found those exposed to both the chemicals were at a 75 per cent greater risk of Parkinson's.

The study, published in the April 15 issue of American Journal of Epidemiology, is the first to provide strong evidence that Maneb and Paraquat act in synergy to become neurotoxic in humans.

Source

Down to Earth, July 2009