Experts reviewing EPA's draft assessment setting first-time inhalation risks for 1,4-dioxane, a ubiquitous Superfund contaminant, are questioning the agency's already final decision to set the chemical's listing to "likely human carcinogen," raising doubts about prospects for revising the classification. Dioxane has long been a concern in drinking water and at Superfund sites, and in recent years environmentalists and public health groups have questioned its appearance in consumer products like soaps and shampoos. In 2007, the Agency for Toxic Substances &...