Bergeson & Campbell, P.C. serves small, medium, and large pesticide product registrants and other stakeholders in the agricultural and biocidal sectors, in virtually every aspect of pesticide law, policy, science, and regulation.

By Timothy D. Backstrom, Lisa M. Campbell, and James V. Aidala

In an opinion issued on September 10, 2015, the U.S. Court of Appeals for the Ninth Circuit vacated the U.S. Environmental Protection Agency’s (EPA) unconditional registration for the pesticide sulfoxaflor and remanded the matter to EPA to obtain further studies and data regarding the effects of sulfoxaflor on bees and bee colonies.  Sulfoxaflor is a new insecticide in the class of insecticides referred to as neonicotinoids, but its mechanism of action is distinct from other neonicotinoids.  The Petitioners in this case were various trade organizations representing commercial beekeepers, as well as some individual beekeepers.  The registrant Dow AgroSciences LLC (Dow) intervened in the action.

EPA granted an unconditional registration for sulfoxaflor on May 6, 2013, subject to a variety of risk mitigation measures, including a lower application rate, longer intervals between applications, and certain crop-specific label restrictions.  EPA had previously proposed to issue a conditional registration for sulfoxaflor in January 2013, citing pollinator data gaps that could be addressed by requiring Dow to conduct and submit further studies.  Under that proposal, use of sulfoxaflor would have been allowed at a reduced application rate during the time needed to complete data development.  The court found that the subsequent decision by EPA to register unconditionally sulfoxaflor was not supported by substantial evidence, as required by Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) Section 16(b), both because EPA failed to adhere to its own scientific methodology and because the rationale that EPA provided for granting an unconditional registration could not be reconciled with the analysis upon which EPA based its prior proposal to register conditionally sulfoxaflor.

EPA evaluated the potential risk to bees and bee colonies from sulfoxaflor use utilizing the Pollinator Risk Assessment Framework, a scientific risk assessment methodology developed after consultations between EPA, Canada’s Pest Management Regulatory Agency, and the State of California, and presented by EPA to the FIFRA Scientific Advisory Panel in 2012.  The court found that the rationale provided for EPA’s unconditional registration decision could not be reconciled with findings that EPA itself made using this methodology or with the rationale EPA provided for its prior proposal to issue a conditional registration.  EPA had decided it was necessary to proceed to Tier 2 of the pollinator risk assessment after reviewing risk quotients and residue data in Tier 1 of the assessment.  EPA found the available data for Tier 2 to be insufficient to allow indefinite use of sulfoxaflor, even at a reduced application rate.  The court could not reconcile this finding with the subsequent decision to grant an unconditional registration, even with the specified mitigation measures.  The court found that “given the precariousness of bee populations, leaving the EPA’s registration of sulfoxaflor in place risks more potential environmental harm than vacating it.”  The court stated that “EPA has no real idea whether sulfoxaflor will cause unreasonable adverse effects on bees, as prohibited by FIFRA.”

EPA argued that with a reduced application rate, the risk quotients and residue analysis in Tier 1  was “close enough” to sufficient to avoid the specified quantitative trigger for a Tier 2 analysis, thereby rendering any deficiencies in the available Tier 2 data irrelevant.  The court effectively stated in response that close enough is not good enough, citing another recent Ninth Circuit decision in which a risk concern that is triggered by a margin of exposure less than or equal to 1000 was held to be triggered when the margin was exactly 1000.  Thus, this court once again placed EPA on notice that it must follow its own methodology with precision, and that EPA cannot justify deviations from its own methodology by simply stating that it is exercising expert judgment.

Commentary

This is an unusual case because the registration of a new pesticidal active ingredient has been vacated on substantive as opposed to procedural grounds.  The court’s rationale reflects a lack of judicial deference to what EPA typically refers to as the scientific “weight of the evidence.”  While the term itself does not appear in the opinion, the court is insisting that EPA must follow its standard methodology without allowing for any deviations based on professional judgment.  Although in this instance the court has supported the position of opponents of pesticide use, judicial reluctance to accept scientific “weight of the evidence” conclusions could also make it harder for EPA to impose additional restrictions when new but inconclusive evidence appears.

This case could cause EPA to be more explicit in adding procedures to its standard analytic methodologies that allow deviations from the methodology based on professional judgment.  The case could also cause EPA to reconsider its recent reluctance to avoid issuing conditional registrations and its preference for unconditional registrations for new active ingredients.  In any case, decisions that afford EPA less discretion to use “weight of the evidence” reasoning when basing scientific conclusions on less than conclusive data or studies could have an impact on a number of EPA practices and policies involving interpretation of scientific data.


 

By Lara A. Hall, Lisa M. Campbell, and Jane S. Vergnes, Ph.D.

 

The release of the first Tier 1 assessments in the Endocrine Disruptor Screening Program (EDSP) by the U.S. Environmental Protection Agency (EPA) on June 30, 2015, is a significant bench-mark in the program since the original List 1 test orders were initially issued in October 2009.  Fifteen of the original 67 List 1 chemicals were subsequently cancelled or discontinued by the respective pesticide registrants.  The intended purpose of the Tier 1 screening was to identify potential interactions of the remaining 52 chemicals with three hormonal pathways (estrogen, androgen and thyroid) in the endocrine system.  EPA evaluated the data from 11 screening assays (five in vitro and six in vivo), along with other scientifically relevant information (OSRI) comprised of existing toxicology studies and peer reviewed published literature, and drew preliminary conclusions about the potential of these 52 chemicals to disrupt endocrine functions. Importantly, EPA noted on the EDSP webpage that “a result indicating potential should not be construed as meaning that EPA has concluded that the chemical is an endocrine disruptor.” 

 

The individually published weight-of-evidence (WoE) assessments and anticipated data evaluation records (DER) can be accessed online for the 52 chemicals involved in the Tier 1 screening assessment.  EPA summarized its conclusions from EPA’s Tier 1 WoE assessments as follows:

 

  1. No evidence of potential interaction with any of the endocrine pathways was identified for 20 chemicals.
  2. Fourteen chemicals showed potential interaction with one or more pathways, but based on the available information, do not pose a risk for endocrine disruption. 
  3. Eighteen chemicals showed potential interaction with the thyroid pathway, 17 of which also showed potential interaction with the androgen pathway, and 14 of which showed potential interaction with the estrogen pathway.

 

To explore further any potential adverse effects on the endocrine system that may be caused by the 18 chemicals that EPA categorized in the third group noted above, EPA has recommended the following Tier 2, multigenerational studies across various species for them:

 

  • A comparative thyroid assay for four chemicals that EPA found to have potential interaction with the thyroid pathway in mammals;
  • The Medaka Extended One Generation Reproduction Test, MEOGRT (Draft Test Guideline OCSPP 890.2200), for 13 chemicals that EPA found to have potential interaction with the estrogen or androgen pathways in wildlife; and
  • The Larval Amphibian Growth and Development Assay, LAGDA (Draft Test Guideline OCSPP 890.2300), for five chemicals that EPA found to have potential interaction with the thyroid pathway in wildlife.

 

EPA has not yet issued its final Tier 2 non-mammalian Office of Chemical Safety and Pollution Prevention (OCSPP) test guidelines (890 Series).  Public comment on the proposed guidelines closed on March 31, 2015.  It is expected that the release of these remaining guidelines will signal the approach of the Tier 2 test orders, which EPA is likely to issue in 2016.  Although a formal public comment period is not expected to be opened for the Tier 1 assessments, affected registrants should have the opportunity to respond directly to EPA regarding WoE assessments and forthcoming DERs. 

 

This release of the Tier 1 WoE assessments, the anticipated release of Tier 2 test guidelines, along with EPA’s commitment to further the development of high-throughput (HTP) assays and computational tools will significantly influence the prioritization of List 2 chemicals in the EDSP and the timing of the List 2 test orders.  The revised List 2 includes 109 chemicals for Tier 1 screening.  As with List 1, List 2 candidates reportedly were selected based on EPA’s review concerning their possible presence in public drinking water and/or registration review status within EPA, and not because of their potential to interfere with the endocrine systems of humans or other species.