EPA Unlawfully Approved Herbicide Enlist Duo

NRDC Petitions Agency to Cancel Registration for the Powerful Weed Killer

WASHINGTON, DC - The Environmental Protection Agency violated the law when it approved use of Dow AgroSciences’ Enlist Duo herbicide and should cancel the registration for the powerful weed killer, according to a petition filed today by the Natural Resources Defense Council (NRDC).

“EPA has already conceded that this powerful weed killer doesn’t meet minimum federal safety standards, yet inexplicably it’s failing to protect people and the environment from dangerous chemicals,” said Sylvia Fallon, Senior Scientist for NRDC. “It’s not complicated: EPA should get Enlist Duo off the market before more people, plants or pollinators are harmed by its poisonous brew.”

Last year, EPA’s own lawyers told a federal judge that Enlist Duo’s registration failed to meet the safety standard set under federal law. The EPA conceded in a court filing that Enlist Duo’s registration should be vacated, telling the Ninth Circuit the agency “did not have all relevant information at the time it made its registration decision.”

Beyond the admission that Enlist Duo does not meet the minimum safety standard, NRDC’s petition argues there are additional strikes against keeping the weed killer on the market, each of which renders the Enlist Duo registration invalid. Since EPA originally approved the herbicide, an international panel of scientists has classified both active ingredients—2,4-D and glyphosate—as possible and probably carcinogens respectively.

However, documents posted online earlier this month indicate the EPA’s cancer assessment panel has determined glyphosate is not a human carcinogen, a position contrary to the world’s leading cancer experts. The EPA later pulled the cancer report from its website, saying the agency had not reached a final determination about the carcinogenicity of the chemical. A final determination is due in December.

The second strike against Enlist Duo’s registration is the EPA’s failure to consider evidence of harm to monarch butterflies, despite a substantial body of scientific literature about the problem. Monarchs are teetering on the brink of extinction due to the loss of a plant it needs to survive, milkweed, which has been decimated by widespread use of glyphosate-based herbicides like Roundup.   For example, in 1999, a survey recorded milkweed was found in at least 50 percent of Iowa corn and soybean fields; in 2009, milkweed was found in only 8 percent of the fields.

Heavy use of glyphosate over the years has resulted in the rise of “super weeds,” which have developed a resistance to standard dosages of herbicides. Chemical maker Dow AgroSciences responded by developing new, genetically-modified corn and soybeans resistant to both glyphosate and 2,4-D. The Agriculture Department predicts Enlist Duo could result in as much as a six-fold increase in the use of 2,4-D, a herbicide developed in the 1940s that has been linked to health impacts in humans, including decreased fertility, birth defects and thyroid problems. Dow won approval to use Enlist Duo over more of the growing season than has been authorized for 2,4-D alone, which could mean wider human exposure.

In a separate action, today NRDC sued the EPA for failing to release documents related to the agency’s decisions to approve, and then expand the approved uses of Enlist Duo to additional states. The request includes access to documents related to the synergistic effects between glyphosate and 2,4-D, as well as the carcinogenicity of both chemicals, among other information. NRDC initially sought these records in December 2015, but the EPA has not yet responded, despite a requirement to do so by January 2016. NRDC is arguing that by failing to disclose records in a timely way, the EPA has violated the Freedom of Information Act. The case was filed in federal court in New York.

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The Natural Resources Defense Council (NRDC) is an international nonprofit environmental organization with more than 2 million members and online activists. Since 1970, our lawyers, scientists, and other environmental specialists have worked to protect the world's natural resources, public health, and the environment. NRDC has offices in New York City; Washington, D.C.; Los Angeles; San Francisco; Chicago; Bozeman, Montana; and Beijing. Visit us at www.nrdc.org and follow us on Twitter @NRDC.

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