A large study by Andrew and colleagues looking at the risk for Amyotrophic Lateral Sclerosis (ALS) based on geospatially estimating exposure to crop-applied pesticides has found an association with several neurotoxic herbicides, insecticides, and fungicides. The study looked at residence at diagnosis of approximately 26,000 nationally distributed ALS patients, and matched non-ALS controls. The he residency data was then related to pesticide exposure risk based on county-level U.S. Geological Survey data on applications of 423 pesticides. The authors concluded that's their findings are consistent with the hypothesis that certain pesticides have neurotoxic effects that increase risk of neurodegenerative disease. Although this study did not look at duration or magnitude of pesticide exposure as this relates to age at onset of ALS, it nevertheless provides additional support for neurotoxic chemical exposures as risk factors for this neurodegenerative disease.
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