We speak with scientist Tyrone Hayes of the University of California, Berkeley, who discovered a widely used herbicide may have harmful effects on the endocrine system. But when he tried to publish the results, the chemical’s manufacturer launched a campaign to discredit his work. Hayes was first hired in 1997 by a company, which later became agribusiness giant Syngenta, to study their product, atrazine, a pesticide that is applied to more than half the corn crops in the United States, and widely used on golf courses and Christmas tree farms. When Hayes found results Syngenta did not expect — that atrazine causes sexual abnormalities in frogs, and could cause the same problems for humans — it refused to allow him to publish his findings. A new article in The New Yorker magazine uses court documents from a class action lawsuit against Syngenta to show how it sought to smear Hayes’ reputation and prevent the U.S. Environmental Protection Agency from banning the profitable chemical, which is already banned by the European Union.