Syngenta, Chevron Say No Link Between Paraquat and Parkinson’s

Syngenta AG and Chevron USA Inc. said there’s no reliable scientific proof linking Parkinson’s disease to paraquat exposure, and urged a federal judge to summarily dismiss claims by test plaintiffs in multidistrict litigation.

Parkinson’s is one of the most common age-related neurological diseases in the world. Thousands of studies by defendants and independent scientists alike have evaluated the safety of the weedkiller, which has been on the market for nearly 60 years, the companies said.

“But after all that research, no study in the peer-reviewed literature concludes that paraquat causes PD,” Syngenta and Chevron said in a filing to Chief ...