House Memorial 42: Parkinson’s Disease and Pesticide Exposure

Executive Summary The NMDOH developed conclusions and recommendations about the potential association of pesticide exposure and Parkinson's disease (PD) based on the literature assessed. Two main categories were analyzed: studies without genetic interactions and studies with genetic interactions. Within these two categories, the following categories of pesticides were identified: 1) general, 2) organochlorine, 3) organophosphorus, 3) botanical, 4) quaternary ammonium, and 5) carbamate or dithiocarbamate. There were many ways in which the reviewed studies described exposure to pesticides, including spraying pesticides, handling or direct contact, using or applying pesticides, performing jobs likely involving pesticide use, or unspecified exposure such as proximity to agricultural spraying. To assess the existing epidemiological evidence for the association between exposure to pesticides and PD that could pertain to specific potentially exposed populations, the reviewed studies were grouped into two broad exposure/use categories: 1) exposure with pesticide use specified, including general use (occupational or residential use could not be distinguished), agricultural use (including farming), other occupational use, and residential use (including gardening), and 2) exposure with pesticide use not specified, including in an agricultural setting, in another occupational setting, in proximity to a pesticide use area, and in a residential setting. Because there are no available data about the specific pesticides historically utilized, the amount, and where these pesticides were used, assessing the risk of pertinent populations in New Mexico is not currently possible. However, the following conclusions and recommendations apply to anyone in New Mexico who uses pesticides. 1. Pesticide Exposure without Genetic Interactions Of the selected studies which addressed exposure to pesticides and the risk of PD, the majority of the evidence suggested an association between PD and pesticide exposure, including: herbicides and insecticides as well as chemical groups of pesticides such as organochlorine (lindane), organophosphorus (chlorpyrifos), quaternary ammonium (paraquat), botanicals (rotenone), and a mixture of dithiocarbamate (maneb) with paraquat. Furthermore, there appears to be good epidemiologic evidence for the association between the general pesticide use category and PD development. The association between PD and more specific pesticide use settings appears to be inconclusive for 1) agricultural use of pesticides, which included farming, 2) other occupational use, and 3) residential use of pesticides, which included gardening. The majority of the studies falling into the exposure with pesticide use not specified category provided inconsistent and inconclusive evidence for 4 the association with PD development. This included pesticide exposure with use not specified in agricultural, other …