Now a federal judge has ruled that there was sufficient evidence for a jury to hear the case that the company's weed-killer, still sold across the United Kingdom, is causing cancer.
U.S. District Judge Vince Chhabria said Tuesday that plaintiffs could present expert testimony linking the product to the cancer, the Associated Press reported.
While the decision means the lawsuits can move forward, the judge noted that it could be a "daunting challenge" to convince him to allow a jury to hear testimony that glyphosate was responsible for individual cancer cases, the AP reported.
The company Monsanto faces 5,000 lawsuits across America as it's alleged that one of their products, Roundup - which is still sold in the United Kingdom - can cause cancer.
Lawsuits by more than 400 farmers, landscapers and consumers who claim Roundup caused them to develop non-Hodgkin's Lymphoma, a type of blood cell cancer, have been consolidated before Chhabria. But he said a reasonable jury could conclude, based on the findings of four experts he allowed, that glyphosate can cause cancer in humans.
Glyphosate is the active ingredient in Monsanto's Roundup herbicide, the most widely used weed-killer in the world.
While Chhabria's ruling is not binding on them, state court judges have been closely following the federal litigation and expert hearings.
The judge wanted to determine whether the science behind the claim that glyphosate can cause non-Hodgkin's lymphoma had been properly tested and met other requirements to be considered valid.
Ritz said a 2017 National Institutes of Health study that found no association between glyphosate and non-Hodgkin's lymphoma had major flaws.
Monsanto developed glyphosate in the 1970s, and the weed killer is now sold in more than 160 countries.
Roundup, made by USA giant Monsanto, is sprayed on gardens and parks and is used by farmers producing food crops.
The U.S. Environmental Protection Agency last September concluded glyphosate is likely not carcinogenic to humans.