Wisconsin dairy farm

One major potential source of endocrine disruptors in the environment: Agriculture. An Iowa State University study estimated land applications of livestock manure accounts for more than 90 percent of the total estrogens in the environment. The U.S. Environmental Protection Agency is concerned about potential impacts on fish. Photo: Kate Golden, Wisconsin Center for Investigative Journalism

One major potential source of endocrine disruptors in the environment: Agriculture. An Iowa State University study estimated land applications of livestock manure accounts for more than 90 percent of the total estrogens in the environment. The U.S. Environmental Protection Agency is concerned about potential impacts on fish. Photo: Kate Golden, Wisconsin Center for Investigative Journalism