EPA Unlawfully Approved Pesticide Enlist Duo, Says NRDC

The Environmental Protection Agency’s (EPA) approval of the weed-killer Enlist Duo was illegal because the agency failed to do a full review of the pesticide as required by law, according to the Natural Resources Defense Council (NRDC), which filed a petition for review today in the U.S. Court of Appeals for the Ninth Circuit challenging EPA’s decision to register Enlist Duo.

“EPA botched its review of Enlist Duo and should have to go back to the drawing board. By ignoring considerable evidence of the risks to both human health and monarch butterflies, EPA is abandoning its mission of protecting people and the environment,” said Sylvia Fallon, senior scientist with NRDC.

Although EPA had previously approved Dow AgroSciences’ Enlist Duo herbicide for use on corn and soybeans in fifteen states, EPA asked the court to pull the previous registration in November, 2015, arguing the agency could no longer vouch for the pesticide’s safety under federal law. Just over a year later in January, 2017, however, EPA issued a new, expanded registration decision approving Enlist Duo – a toxic combination of the chemicals glyphosate and 2,4-D – for use on herbicide resistant corn, soybeans, and cotton in thirty-four states.

Glyphosate is also linked to cancer, according to the world’s leading cancer authority, the International Agency for Research on Cancer (IARC), which determined glyphosate is probably carcinogenic to humans. In contrast, Monsanto and EPA’s pesticide office say the chemical likely doesn’t cause cancer.  Yet even EPA’s science research office disagrees with the EPA’s official position, according to recent documents made public through legal discovery in a federal case challenging the safety of glyphosate. Both the EPA science research office and EPA’s external Scientific Advisory Panel warned that the pesticide office had failed to follow accepted scientific practices and Agency guidelines for conducting cancer assessments.

A growing body of research also suggests that glyphosate may pose serious non-cancer health risks, such as liver and kidney toxicity. In addition, IARC found that Enlist Duo’s other active ingredient, 2,4-D, is possibly carcinogenic to humans. The EPA’s failure to fully consider Enlist Duo’s health risks before approving the pesticide violates the law and puts public health at risk.

EPA also failed to give proper consideration to the impact of Enlist Duo on monarch butterflies Both glyphosate and 2,4-D threaten the imperiled monarch population, because both destroy milkweed, the sole food source for monarch caterpillars. The introduction of crops that are genetically engineered to resist herbicides has led to a vast expansion in herbicide use, eliminating large amounts of milkweed from farmland in the Midwest.  The resulting loss of critical breeding ground for monarchs has decimated the migrating monarch butterfly population, which has plunged nearly ninety-percent from a peak of over one billion two decades ago to near record lows in the most recent count released last month.

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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, MT, and Beijing. Visit us at www.nrdc.org and follow us on Twitter @NRDC.