The ruling is the latest blow to Bayer and Monsanto, which have been hit with billions in additional damage awards already this year, as Roundup lawsuits continue to go before juries nationwide.
Landscaper diagnosed with non-Hodgkins lymphoma from Roundup was awarded $250 million in compensatory damages, plus $2 billion in punitive damages against Bayer and Monsanto.
A Philadelphia jury awarded $3 million in punitive damages in a Roundup lawsuit verdict returned this week, in the latest of a series of trials scheduled over the next year.
Three plaintiffs were each awarded $500 million in punitive damages, which the jury leveled against Bayer and Monsanto to punish the makers of Roundup for disregarding consumer safety.
The U.S. Court of Appeals for the Ninth Circuit has determined that the state of California can not require Roundup cancer warnings, finding that it would violate the manufacturer's First Amendment rights.
A San Diego jury has determined Bayer and Monsanto should pay $7 million in compensatory damages, and an additional $325 million in punitive damages for failing to warn about the risk of non-Hodgkins lymphoma from Roundup.
The verdict includes $150 million in punitive damages against Monsanto and its parent company, Bayer, for withholding information about the link between NHL and Roundup.
The denial is the third time the Supreme Court has refused to overturn a Roundup lawsuit decision.
The study calls for more research into the metabolic risks of Roundup exposure, and not just focusing on the weed killer's cancer risks.
Researchers linked exposure to Roundup among farmers to increased oxidative stress, which is a known biomarker of increased cancer risks.
