Atrazine, a triazine herbicide commonly used on corn, poses a risk to many plants and animals, including fish, amphibians, mammals, birds, and reptiles, concludes an EPA draft ecological assessment. Atrazine is persistent in the environment and moves readily into surface and groundwater, EPA says. The agency predicts that average atrazine concentrations above 5 µg/L in water can lead to reproductive effects in fish. Many waters in the heaviest corn-growing areas of the U.S. exceed that level, EPA notes. Atrazine and related herbicides exhibit neuroendocrine effects in mammals and have been shown to alter hormone levels in rats, potentially leading to developmental and reproductive effects, according to EPA. Many farmers worry that EPA will use the assessment to restrict atrazine use. Maryland farmer Chip Bowling, president of the National Corn Growers Association, claims that EPA based its assessment on flawed studies. Atrazine “is among the most reliable herbicides available,” he says, adding that the herbicide has passed rigorous safety testing over the past 50 years.