A Fresno County Superior Court judge has ruled against chemical giant Monsanto in its fight to prevent California regulators from listing the key ingredient in its popular weed killer Roundup as a carcinogen.

The tentative ruling, issued Friday by Judge Kristi Culver Kapetan, was welcomed by environmental advocates, their attorneys and those who say they got cancer from using the weed killer.

“I don’t want anyone to go through what I have gone through,” said John Barton, a Bakersfield farmer who believes the use of Roundup caused his non-Hodgkin lymphoma.