German pharmaceutical group Bayer has seen a steep drop in sales following a US verdict ordering its subsidiary, agricultural giant Monsanto, to pay damages to a man who said ingredients in one of its weedkillers had caused his cancer.
On Friday, a California judge ordered Monsanto to pay $289m (£226m) to claimant Dewayne Johnson, suffering from terminal non-Hodgkins’s lymphoma. By Monday, Bayer’s shares had lost 10.4% of their value.
Mr Johnson is among more than 5000 other plaintiffs across the US claiming that Monsanto’s Roundup and RangerPro weedkillers have caused their illness. The chemical in question, glyphosate, was introduced by Monsanto in 1974 but its patent expired in 2000 and it is now sold by several manufacturers. In 2015, the International Agency for Research on Cancer, WHO’s dedicated cancer agency, stated that glyphosate was ‘probably carcinogenic to humans’.

But there is still some debate over this, with Reuters even claiming last year that the WHO agency had 'edited out' its non-carcinogenic findings. Bayer – which completed its takeover of Monsanto in June this year – insists the product is safe and is backed up by the US Environmental Protection Agency which says the product is safe ‘when used carefully’. The European Food Safety Authority also says that the chemical is unlikely to cause cancer, and last year – despite opposition – EU countries voted to renew its licence.
Even so, the jurors in the trial found on Friday that Monsanto had acted with ‘malice’ and its weedkillers had contributed ‘substantially’ to Mr Johnson’s illness. It further added that Monsanto should have warned users regarding the dangers of using its Roundup and RangerPro products. The ongoing controversy has caused many to question the future of glyphosate in the industry.
Monsanto has stated it will be appealing the verdict.