German pharmaceutical and chemical giant Bayer has disclosed that 9,300 plaintiffs are suing them as of the end of October, alleging that that Roundup weed killers cause cancer. Bayer acquired the product in their $63 billion purchase of Monsanto.

The plaintiffs claim that weed-killing products containing glyphosate have made them ill, and that the company knew or should have known the health risks, yet failed to adequately warn consumers of them. Monsanto claims that the compound is safe to use.

"We continue to believe that we have meritorious defenses and intend to defend ourselves vigorously in all of these lawsuit," said Bayer CEO Werner Baumann - however he added that "more lawsuits are to be expected."

"Glyphosate is an indispensable chemical for modern agriculture that is safe to use, very effective and saves resources," said Baumann. "When used appropriately, glyphosate is a completely safe and good product ... completely safe."

In August, a San Francisco jury disagreed - awarding $289 million in damages to former school groundskeeper Dewayne Johnson, however he walked away with $78 million after the judge reduced his award.

Bayer said there were 8,700 lawsuits pending against the company as of the end of August - which could cost the company billions in damages in the coming years.

In September, 2017 the US Environmental Protection Agency (EPA) concluded that glyphosates were not likely carcinogenic to humans, based on a decades-long assessment. In 2015, the World Health Organization (WHO)'s cancer arm issued an opposite statement - warning that glyphosate was "probably carcinogenic to humans."