EPA to Keep Groundwater Warnings on Labels of Cyanazine
WASHINGTON (AP) _ The Environmental Protection Agency said today it would keep groundwater warnings on labels of cyanazine, a herbicide used on up to a quarter of the U.S. corn crop, despite lessened concerns about groundwater contamination.
Cyanazine, sold by DuPont Co. under the trade name Bladex, poses a risk of birth defects in workers exposed to it, according to studies on laboratory animals, EPA said. The agency described the risk of dietary exposure as negligible.
In 1985, the agency began a special study of the chemical and restricted use to state-certified applicators. In December 1986, EPA proposed requiring closed mixing systems, protective clothing and special handling of that clothing, and label warnings of the possiblity of birth defects.
Because of reports of contamination of groundwater, it also proposed a label statement advising against use on highly permeable soils and where water tables are high.
Those draft requirements were adopted for the 1987 growing season while EPA considered public comment.
In adopting the requirements as a permanent regulation, EPA said today new data showed no detectable cyanazine in 400 samples taken from 200 wells in two East Coast counties and two counties in the Midwest.
″Based on the new data, EPA no longer believes that cyanazine should be classified for restricted use based on groundwater concerns,″ the agency said.
″However, because some instances of contamination were reported in earlier studies, the groundwater advisory statement will remain on the label,″ it said.
When EPA began its cyanazine proceedings, the herbicide was made by Shell Chemical Co., but Shell’s pesticide business in the interim was sold to DuPont.