According to Rodale.com, well-meaning organic gardeners are sometimes tricked into buying toxic compost. Although the sludge industry has convinced many that sludge is cheap and safe (thanks in part to an expensive PR campaign), a 2011 U.S. Environmental Protection Agency (EPA) survey, that collected sewage sludge from 74 randomly selected publicly owned treatment works in 35 states, concluded that all sewage sludge contains toxic and hazardous materials.