The question of cause is already proving contentious in the Parkinson’s disease lawsuits; judges have ruled that they won’t allow testimony from an expert on whether paraquat is capable of causing Parkinson’s disease in the lead up to the first trial, scheduled to start in October. As a result, epidemiological studies that demonstrate links to paraquat exposure and cell-based studies revealing how paraquat damages dopamine cells may be even more important.
“In every other country, industry has to bring a chemical to the regulatory agency with proof that it’s safe,” says Kyla Bennett, director of science policy at the Public Employees for Environmental Responsibility. “In the U.S., it’s more like, ‘Here’s the chemical. [EPA] has 90 days to prove it’s dangerous.’ It’s totally backwards.”