Mary, although I can't help you with your search the question about the influence of herbicides and pesticides on the development of neurological disorders/diseases fascinate me. My father develped Parkinson's about four years ago with no known family hhistory. He has worked around the railroad for at least 45 years and constantly was exposed to the defoliants and other sprays that were used to keep weeds down along the tracks. A friend of his, who worked the railroad for almost as many years, died a couple of years ago with a malignant brain tumor. He was in his mid-fifties with no family CA hx. Maybe someone who reads this message can at least let us know if there is any valid correlation or at least is anyone looking into this relationship. Thanks for bringing this topic up. Sharon Hall ([log in to unmask])