By MARY CLARE JALONICK
Associated Press WASHINGTON (AP) - The Environmental Protection Agency has approved a new version of a popular weed killer to be used on genetically modified corn and soybeans.
The EPA said Wednesday that it will allow the use of a 2,4-D weed killer called Enlist Duo, a new version of the popular herbicide used since the 1940s. It is designed to be used on corn and soybeans grown with engineered seeds approved by the Agriculture Department last month. When used together, farmers can spray the fields after the plants emerge, killing the weeds but leaving crops unharmed.
The agriculture industry has anxiously awaited the approvals, as many weeds have become resistant to glyphosate, an herbicide commonly used on genetically modified corn and soybeans now. Enlist includes a combination of both 2,4-D and glyphosate.
Critics say they're concerned the increased use of 2,4-D could endanger public health and more study on the chemical is needed. The USDA has said that if both the seeds and herbicide are approved, the use of 2,4-D could increase by an estimated 200 percent to 600 percent by the year 2020.
The EPA said in a release that the agency's decision reflects a large body of science and that officials used "highly conservative and protective assumptions to evaluate human health and ecological risks." The EPA said the herbicide meets safety standards for the public, agricultural workers and endangered species.
2,4-D is now used on other crops, including wheat, and on pastures and home lawns. It is the world's most popular herbicide and the third most popular in the United States, behind atrazine and glyphosate.
Groups lobbying the agency to prevent the herbicide's expanded use say they are concerned about the toxic effects of the herbicide and the potential for it to drift. Corn and soybeans are the nation's largest crops, and the potential for expanded use is huge.
Dow AgroSciences, which manufactures Enlist, says the new version has been re-engineered to solve potential problems, like drift before and after the herbicide hits the plant.
To further address concerns, the EPA is requiring a 30-foot buffer zone where the herbicide can't be sprayed. The agency is also requiring farmers to stop spraying if wind speed is over 15 miles an hour.
Wednesday's announcement approves the use of the weed killer in six states: Illinois, Indiana, Iowa, Ohio, South Dakota and Wisconsin. The agency is taking comments on whether to register the herbicide in 10 additional states: Arkansas, Kansas, Louisiana, Minnesota, Missouri, Mississippi, Nebraska, Oklahoma, Tennessee and North Dakota.
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