Parkinson's probably has several causes, including genetic factors, but the clearest link is to exposure to environmental neurotoxins, especially organophosphat

Parkinson's probably has several causes, including genetic factors, but the clearest link is to exposure to environmental neurotoxins, especially organophosphate pesticides. Studies on the incidence of Parkinson's in agricultural areas where organophosphates, e.g. paraquat, maneb, were heavily used had a significantly higher risk of developing PD. The study showed a strong correlation between long-term pesticide exposure and PD onset. See: https://www.nature.com/articles/s41467-023-38215-z https://www.nature.com/articles/s41467-023-38215-z