On December 6, 2019, the European Union (EU) announced that it will no longer permit sales of chlorpyrifos after January 31, 2020.  The Standing Committee on Plants, Animals, Food and Feed (PAFF Committee) voted in favor of two draft Implementing Regulations that denied the renewal of approvals for chlorpyrifos and chlorpyrifos-methyl.  The European Commission is expected to formally adopt the regulations in January 2020.  At that time, Member States will need to withdraw authorizations for products containing chlorpyrifos and chlorpyrifos-methyl as active substances and may implement a grace period, at a maximum of three months, for final storage, disposal, and use of the substances.

The ban in the EU follows increased concerns over the human health effects of the substances.  On August 2, 2019, the European Food Safety Authority (EFSA) published a report concluding that no safe exposure level could be determined for chlorpyrifos and that based upon available data, the approval criteria under Article 4 of Regulation (EC) No 1107/2009 for human health were not met.  EFSA also published an updated statement reiterating the same conclusion for chlorpyrifos-methyl on November 26, 2019.  EFSA’s primary health concerns were potential developmental neurotoxicity based on the available animal data and epidemiological evidence, and unresolved concerns regarding potential genotoxicity.  EFSA also concluded that toxicological reference values could not be established for either of these effects, thereby precluding a valid risk assessment for consumers, workers, or bystanders.

Prior to the PAFF Committee meeting, eight EU states had already banned or never approved the use of chlorpyrifos.  Canada proposed a ban of chlorpyrifos on May 31, 2019.  (More information on this proposal is available in our blog post).

Within the United States, state governments have taken steps to regulate chlorpyrifos.  On June 13, 2018, Hawaii passed an act that banned the use of pesticides containing chlorpyrifos as an active ingredient beginning January 1, 2019.

Several recent actions in California culminated in a ban on chlorpyrifos.  First, the California Department of Pesticide Regulation (DPR) decided that chlorpyrifos should be designated as a Toxic Air Contaminant.  This action was based primarily on a point of departure derived from new animal studies that report neurodevelopmental effects well below the level that inhibits cholinesterase.  On August 14, 2019, DPR issued cancellation notices for chlorpyrifos products based primarily on the same new animal data.  DPR subsequently announced on October 9, 2019, an agreement with pesticide manufacturers to end the sale of chlorpyrifos by February 6, 2020.  Growers will not be able to possess or use chlorpyrifos products in the state after December 31, 2020.

In New York State (NYS), recent efforts to ban the substance through legislation were unsuccessful.  On December 10, 2019, NYS Governor Andrew Cuomo vetoed a bill passed by the NYS Legislature (A.2477/S.5343) to phase out chlorpyrifos from use by December 1, 2021.  Governor Cuomo stated that the NYS Department of Environmental Conservation is responsible for taking regulatory action on the issue, but recommended that the agency implement its own phased-in ban of chlorpyrifos.

On the federal level, chlorpyrifos products remain registered and have been since 1965.  The U.S. Environmental Protection Agency (EPA) has taken measures to restrict the use of chlorpyrifos within households and on particular crops, but some non-governmental organizations (NGO) have long advocated that chlorpyrifos should be banned in its entirety.  On September 12, 2007, the Pesticide Action Network North America (PANNA) and the Natural Resources Defense Council (NRDC) filed a petition requesting that EPA revoke all tolerances and cancel all registrations for chlorpyrifos.  EPA’s failure to respond fully to this petition was the subject of several decisions in the 9th Circuit Court of Appeals, and the Court ultimately issued a writ of mandamus requiring that EPA take final action concerning the petition.

At one point, EPA proposed to revoke all tolerances for chlorpyrifos.  This action was based in part on a controversial determination that EPA should reinstate the default safety factor for tolerance assessments under the Food Quality Protection Act (FQPA) for all organophosphate (OP) pesticides.  This determination was based on developmental neurotoxicity associated with chlorpyrifos exposure in certain epidemiology studies.  After further deliberation and a change of administrations, EPA issued an order denying the 2007 petition in its entirety on March 29, 2017, based in part on a conclusion stating that further evaluation was needed to properly assess potential neurodevelopmental effects of chlorpyrifos.  EPA later issued a final order that denied all objections to the March 2017 petition denial order.  A number of NGOs (including the original petitioners) and several states have challenged this decision, filing petitions on August 8 and August 9, 2019, respectively for judicial review of EPA’s final order retaining tolerances and registrations for chlorpyrifos.  EPA has stated that it intends to complete its evaluation of the epidemiology studies for chlorpyrifos, as well as the new animal data relied on by California, in the context of the pending registration review of chlorpyrifos under Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) Section 3(g).  A final registration review decision concerning chlorpyrifos is due by October 1, 2022, although EPA has stated that it intends to accelerate that process. 

Commentary

At this juncture, the long-term impact of the gradual accumulation of adverse decisions on chlorpyrifos from EFSA and various other governmental agencies is uncertain.  Most user groups in the United States continue to describe chlorpyrifos as an essential agricultural tool.  Some commodities treated with chlorpyrifos are destined for export markets where chlorpyrifos has been banned, however, and the impacts of this change will need to be monitored closely.

EPA’s interpretation of the epidemiology studies for chlorpyrifos remains controversial in the scientific community.  Indeed, although the EFSA conclusion is predicated in part on these epidemiology studies that are the basis of the controversial EPA interpretation, the wording of the EFSA report indicates that there were some dissenters.  Moreover, the extension of EPA’s FQPA determination for chlorpyrifos to other organophosphate (OP) pesticides has never been satisfactorily explained.

The NGOs and states that have challenged EPA’s final order refusing to revoke the tolerances and cancel the registrations for chlorpyrifos will argue that the final order cannot be reconciled with EPA’s prior scientific determinations.  Even if EPA can successfully rebut those arguments, there is also a possibility that EPA’s own review of the new animal chlorpyrifos studies may obviate that controversy.  On balance, the remaining manufacturers and registrations for chlorpyrifos are likely to confront a variety of challenges in the coming months.