More than 42,000 plaintiffs have joined lawsuits against German chemical giant Bayer, blaming the company's glyphosate-based weedkiller for their cancer.
The number of plaintiffs, largely brought by US citizens, is now at 42,700 — more than double the 18,400 reported in the middle of July, Bayer announced on Wednesday.
The legal cases all concern Roundup, a weedkiller with controversial active ingredient glyphosate.
"This significant increase is clearly driven by the plaintiff-side television advertising spend which is estimated to have roughly doubled in the third quarter compared with the entire first half of the year," Bayer said in a statement.
"However, the number of lawsuits says nothing about their merits," it added.
Claims against the company gathered momentum following a lawsuit in August 2018 that found Monsanto, a Bayer subsidiary, should have warned of alleged cancer risks associated with its glyphosate-based weedkillers.
Bayer's shares have dropped 30% since then.
The company said it was engaged in a mediation process ordered by a federal judge in California.
In 2015, the World Health Organization's International Agency for Research on Cancer (IARC) said glyphosate, the world's most commonly used herbicide, was "probably carcinogenic to humans."