A bottle of Monsanto's Roundup herbicide in a gardening store in Lille, France. A group convened by the European Food Safety Agency reviewed the available scientific data on the chemical, also known as glyphosate, and concluded that it probably does not cause cancer. Philippe Huguen/AFP/Getty Images hide caption

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A farmer holds Monsanto's Roundup Ready soybean seeds at his family farm in Bunceton, Mo. Dan Gill/AP hide caption

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