California’s highest court rejected on Wednesday a challenge by Monsanto Co. to $86.2 million in damages to a couple who developed cancer after years of spraying Roundup herbicide on their property. Roundup, a glyphosate-based weed-killer, has been on the market since the 1970s. Glyphosate, the most commonly used herbicide around the world, kills grasses and broadleaf plants. The International Agency for Research on Cancer (IARC), which is part of the World Health Organization, listed glyphosate as a probable carcinogen in 2015. The First District Court of Appeal in San Francisco found in a 2–1 ruling in August that Monsanto was at fault for knowingly marketing a product in which the active ingredient could be dangerous, according to the San Francisco Chronicle. The state Supreme Court’s denial of review upheld the Aug. 9 appeals court’s ruling in favor of Alva and Alberta Pilliod, the couple from Livermore. Monsanto’s parent company, Bayer, said …