Link Between Paraquat and Parkinson’s Disease

One of the first indications of the potential neurological effects of paraquat exposure came in the 1980s, when an experiment revealed that MPTP, a heroin contaminant that shares a similar chemical structure to paraquat, destroys dopamine neurons – the same neurons that are damaged in Parkinson’s patients. Additional research studies conducted over the past several decades have established an even stronger association between paraquat exposure and the development of Parkinson’s disease, a debilitating neurodegenerative disorder that affects 10 million people worldwide.

In one study published in the American Journal of Epidemiology in 2009, researchers found that exposure to paraquat and a fungicide called maneb sprayed within 500 meters of a person’s home increased their risk of Parkinson’s disease by as much as 75%. Another study published in 2011 suggested that farmers who use paraquat are two-and-a-half times more likely to develop Parkinson’s disease. Other research has linked paraquat exposure during a person’s teen and young adult years to an increased Parkinson’s risk landing somewhere between 200% and 600%.

Despite these increasingly alarming findings, many of which date back a decade or more, it wasn’t until 2016 that the EPA announced that it would conduct a review of the potential health risks of paraquat exposure, including its possible link to Parkinson’s disease. Unfortunately, the agency has until October 2022 to make a decision about the use of paraquat moving forward, which means the potentially harmful herbicide will continue to be used in the meantime.