A judge in the US state of California has upheld a jury's ruling that Monsanto's glyphosate-based herbicide Roundup caused a school groundskeeper's cancer, while at the same time reducing the punitive damage compensation awarded by the jury to DeWayne Johnson.

In cutting the award from $250 million to $39 million, the same amount the jury awarded for other damages in August yielding a total of $78 million, San Francisco Superior Court Judge Suzanne Bolanos gave Johnson until Dec. 7 to accept the lower payout or demand a new trial.              

Bolanos suggested in a preliminary ruling on Oct. 11 that the jurors may have “overreached” in their damage award, especially as attorneys for the plaintiff had produced no compelling evidence that Monsanto employees ignored evidence that the herbicide could cause cancer.

In making a final recommendation, however, the judge said she was obliged to honor the jurors' conclusions after they listened to expert witnesses debate the merits of the claim for six weeks. According to the newspaper San Francisco Chronicle, “some jurors were so upset by the prospect of having their verdict thrown out that they wrote to Bolanos.”

Johnson's lawsuit is the first of thousands s alleging that glyphosate causes cancer to go to trial. As the new owner of Monsanto and the Roundup business, Germany’s Bayer group is now liable for any litigation.

Estimates as to the number of glyphosate cases pending in US courts range from at least 4,000 to as many as 5,000, according to estimates circulating in August.