EPA Approval of Enlist Duo Pesticide Violates Federal Law, Petition Claims

Environmentalists and farmers petitioned federal regulators last week, seeking to reverse the approval of Enlist Duo, an herbicide that combines two active ingredients that critics say become more toxic when mixed together. 

The National Family Farm Coalition, the Center for Biological Diversity, the Natural Resources Defense Council and several other groups filed a petition (PDF) against the U.S. Environmental Protection Agency (EPA) and it’s commissioner Scott Pruitt on April 11, challenging the EPA’s expanded approval of Enlist Duo, a Dow pesticide that combines glyphosate, the active ingredient in Roundup, and 2,4- dichlorophenoxyacetic acid (2,4-D).

Early last year, the EPA expanded approval of Enlist Duo in 34 states, for use on corn, cotton and soybean crops that have been genetically modified to withstand the pesticide. However, the petition, filed in the U.S. Court of Appeals for the Ninth Circuit, claims that the EPA failed in its mission to protect the environment, farms, public health and endangered species.

The approval came despite a 2015 EPA review, which found that Dow made claims of a “synergistic” effect between glyphosate and 2,4-D, which could make the two chemicals more toxic. The information was discovered in patent documents, but the EPA claims Dow never informed the agency that the two could become more powerful, and potentially more dangerous, when combined.

The EPA indicates that it contacted Dow after discovering the synergism claims, and warned the company that this would assess how the regulators factored the potential impacts to non-target organisms. Dow responded with more data, which the EPA is still reviewing. However, the preliminary findings led EPA reviewers to conclude that a 30-foot buffer it required around application areas for Enlist Duo may be insufficient.

Despite those concerns, the EPA granted expanded approval of the herbicide after the new administration came into office in early 2017.

“EPA has put human health, neighboring crops, and the survival and recovery of hundreds of endangered species at risk by recklessly putting a potent and toxic pesticide on the market without the data or expert review the law requires,” Paul Achitoff, an attorney with Earthjustice said in a press release. “We, and the law, demand much more from the agency created to protect our health and environment than bowing to chemical industry pressure.”

Glyphosate, the active ingredient most known for its use in Monsanto’s weed killer Roundup, was deemed to be a probably carcinogen in March by the International Agency for Research on Cancer (IARC), an arm of the World Health Organization. The designation has led some countries to ban Roundup and other glyphosate-based pesticides.

Monsanto now faces hundreds of Roundup lawsuits by agricultural workers who say they have been diagnosed with non-Hodgkin’s lymphoma due to long-term exposure to glyphosate.

The chemical 2,4-D was used in Agent Orange, a defoliant during the Vietnam War, which has been linked to a number of illnesses afflicting veterans of the war.

The petition calls for the appeals court to vacate the EPA’s approval, saying that the agency violated both the Endangered Species Act and the Federal Insecticide, Fungicide, and Rodenticide Act.