The U.S. Environmental Protection Agency has approved the registration of Dow Chemical’s Enlist Duo herbicide, a new blend of 2,4-D and glyphosate. The product is intended for use on Dow’s Enlist genetically engineered corn and soybeans, which were approved by the Department of Agriculture last month. Dow stated in a press release that EPA’s decision means that the company can “bring to the market this necessary, innovative technology that is expected to deliver significant growth for Dow while at the same time addressing a critical global challenge.” The combination of the two chemicals “will control and help prevent further development of herbicide-resistant weeds,” the company said. A number of farm, food, health, public interest, consumer, fisheries and environmental organizations submitted comments in opposition to both proposals, arguing that its use on millions of acres of farm fields could negatively impact both environmental and human health. Members of Congress and prominent doctors, scientists and researchers also expressed their opposition. 2,4-D was a component of Agent Orange, which was produced by Dow and Monsanto and used as a defoliant in Vietnam, and glyphosate is the active ingredient in Roundup, the top-selling weed killer developed by Monsanto. The opposition groups are particularly concerned about the health risks associated with 2,4-D exposure, including non-Hodgkin lymphoma, suppressed immune function, lower sperm count, and a greater risk of Parkinson’s disease. There are also risks of learning disabilities, behavioral problems and chronic diseases in children. In terms of environmental effects, critics say that Enlist Duo will increase soils, surface and groundwater contamination and perpetuate the “pesticide treadmill,” which is when farmers use larger amounts of increasingly toxic chemicals to control herbicide-resistant weeds, eventually requiring the use of different chemicals. Now that EPA has announced its approval of Enlist Duo, these groups are outraged. “EPA has turned its back on those it purports to protect — the American people and our environment,” said Andrew Kimbrell, executive director for the Center for Food Safety. He added that his organization will “pursue all available legal options to stop the commercialization of these dangerous crops.” The Natural Resources Defense Council filed a petition in the U.S. Court of Appeals for the District of Columbia Circuit immediately after the announcement Wednesday, asking that the court block Enlist Duo’s unconditional registration. Ronnie Cummins, international director of the Organic Consumers Association (OCA), argued that now it’s time for consumers to “shut down this treadmill of higher doses of increasingly toxic poisons.” OCA now plans to put more effort into its campaigns for mandatory GMO-labeling laws and for federal policies that promote organic agriculture. Rep. Peter DeFazio (D-OR) said that, “EPA shunned its duties to protect the environment and safeguard public health by bowing to corporate interests instead of relying on science.”