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October 29, 2015

Environmental Groups File Opening Briefs Challenging EPA’s Decision to Register Enlist Duo

Lisa M. Campbell Lisa R. Burchi James V. Aidala

On October 23, 2015, in the U.S. Court of Appeals for the Ninth Circuit, the Natural Resources Defense Council (NRDC) and other environmental groups including the Center for Food Safety (CFS, et al.) (together, Petitioners) filed separate opening briefs in Case Nos. 14-73353 and 14-73359 (consolidated) arguing that the U.S. Environmental Protection Agency’s (EPA) decision to register Dow AgroScience’s Enlist Duo herbicide (a combination of glyphosate and 2,4,-D) for use on Enlist corn and soybeans should be overturned because it violates the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and the Endangered Species Act (ESA).   EPA approved Enlist Duo for use in six states on October 15, 2014, and granted an amendment on March 31, 2015, to authorize use in an additional nine states.  On August 11, 2015, the Court of Appeals denied motions for a stay pending review that were filed by these same environmental Petitioners on December 18, 2014, and February 6, 2015.   See “Ninth Circuit Denies Requests to Stay Use of Enlist Duo Herbicide During Judicial Review.”

In its brief, NRDC notes that when EPA proposed to register Enlist Duo, it stated that no new assessment is needed for glyphosate because use of glyphosate on herbicide-resistant crops is not a new use.  NRDC argues that there are many new studies concerning glyphosate’s human health effects and impacts on monarch butterflies since EPA reregistered glyphosate and last prepared comprehensive environmental and human health assessments in 1993. NRDC argues that “By failing to consider up-to-date science on glyphosate’s cancer risk, EPA again violated its statutory duty to ensure that registration of Enlist Duo would not cause ‘unreasonable adverse effects on the environment,’ which includes an unreasonable risk to human health.”

In their brief, CFS, et al. argue that EPA violated FIFRA by ignoring its own modelling indicating that risks to wildlife from Enlist Duo exceed EPA’s risk thresholds.  CFS, et al. also focus on purported violations of the ESA, arguing that EPA improperly failed to consult with the U.S. Fish and Wildlife Service on the potential impacts of Enlist Duo on protected species and their critical habitat, and that EPA applied an “unlawful approach” to determine whether registration of Enlist Duo “may affect” listed species or critical habitats.

NRDC also filed a motion to supplement the record with three documents that it states were submitted to EPA, but it contends were not considered by EPA before it issued its registration decision for Enlist Duo.  The documents include an article published by the World Health Organization’s (WHO) International Agency for Research on Cancer stating that glyphosate is “probably carcinogenic to humans”; a statement published by WHO in conjunction with its cancer finding, and a letter from NRDC and other concerned parties calling on EPA to reconsider its initial decision to register Enlist Duo in light of the WHO’s cancer finding.

Discussion

Petitioners’ arguments in these opening briefs are not unexpected, as pesticide products containing glyphosate have been challenged and controversial for many years.  In briefs opposing the prior stay motions by the Petitioners, EPA and the registrant Dow AgroSciences argued that registration of Enlist Duo will not lead to any increase in the use of glyphosate, and that EPA also considered all of the human health effects of 2,4-D before granting the registration.  The Petitioners acknowledge that EPA did not state when it last conducted environmental and human health assessments for glyphosate, and EPA is likely to object to Petitioners’ inference that EPA has not reviewed the environmental and health effects of glyphosate since 1993.  In the fact sheet concerning its decision to register Enlist Duo, EPA states that it conducted a “rigorous analysis” of all the scientific studies, considered all public comments, and used worst-case estimates when assessing the safety of Enlist Duo.  In addition, the Petitioners do not discuss the determination by the the U.S. Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS), that three varieties of herbicide resistant corn and soybeans on which Enlist Duo will be applied are no longer considered regulated articles under regulations governing the introduction of certain genetically engineered organisms, because they are unlikely to pose a plant pest risk.

EPA and Dow AgroSciences’ answering briefs are due December 18, 2015, and reply briefs are due January 15, 2016.  Oral argument has not yet been scheduled.