The Office of Health Assessment and Translation at the National Institute of Environmental Health Sciences is conducting two scoping reviews looking at the evidence showing an association between exposure to environmental chemicals and Parkinson’s disease. We hope the evidence gleaned by this study will be used by the EPA in its assessment of paraquat’s registration. See the initial protocol here: https://ntp.niehs.nih.gov/ntp/ohat/parkinson/parkinsons_protocol_508.pdf