On January 3, 2018, the California Department of Pesticide Regulation (DPR) issued Notice 2018-01: Expanding Use of Pesticide Products Under Reevaluation. Under Notice 2018-01, effective immediately, DPR will not act upon an Application for Pesticide Registration or an Application to Amend a Pesticide Product if it determines the registration or acceptance would potentially “expand use” of an active ingredient or pesticide product currently under reevaluation until the conclusion of the reevaluation.

DPR states that it commences a reevaluation of an existing registered pesticide when it finds, based on an investigation of all reported episodes and information received, that a significant adverse impact to human health or the environment has occurred or is likely to occur. DPR states that the policy set forth in Notice 2018-1 is needed for pesticides under reevaluation because until DPR reviews existing data for substances under reevaluation, determines whether additional data to satisfy reevaluation data requirements must be submitted, and then receives and assesses additional data applicable to the reevaluation that can mitigate the concern that prompted the initiation of the reevaluation, DPR “is not in a position to determine that an expanded use will not cause a ‘significant adverse environmental impact,’ as required under its certified regulatory program (3 CCR section 6254).” Once the reevaluation process is completed, DPR states that it will then be in a position, in light of its reevaluation determination, to consider applications for product registration or amendment.

Scope of Notice 2018-1

DPR is currently reevaluating certain pesticide products containing the following active ingredients:

  • Chloropicrin;
  • Copper-based antifouling paints (copper oxide, copper hydroxide, and cuprous thiocyanate);
  • Cyfluthrin;
  • Diazinon; and
  • Nitroguanidine neonicotinoids (imidacloprid, thiamethoxam, clothianidin, and dinotefuran).

This notice applies to new pesticide products that include these active ingredients, including supplemental distributor registrations (subregistrations) and amendments to currently registered pesticide products, when “expanding use” of the active ingredient relevant to the concern that prompted the reevaluation.

Specifically, DPR states in Notice 2018-1 that it interprets the following types of actions, related to a new or amended product containing the active ingredient under reevaluation, as examples of “expanding use”:

  • A proposed new pesticide product, including any Special Local Needs registration or Experimental Use Permit, with a label bearing uses or exposure scenarios relevant to the concern that prompted the reevaluation. This includes any product label that is identical or substantially similar to a currently registered product in California.
  • Amendment of a currently registered product to add or modify uses or exposure scenarios relevant to the concern that prompted the reevaluation, even if such use is already on other currently registered pesticide products in California. Examples of such changes include:
    • New or modified uses (e.g., new crops, pests, or use sites);
    • New or modified use patterns (e.g., adding aerial, aquatic, soil applications, or outdoor use);
    • Significant formulation changes (unless prompted by the reevaluation);
    • Increased application rates or total use amount allowed (e.g., acreage or frequency of application); and
    • Other label additions or changes that may increase pesticide exposure in a manner that is relevant to the basis for the reevaluation.

This notice does not preclude expanded use of a product if the expansion is not consistent with uses or exposure scenarios relevant to the concern that prompted the reevaluation. As an example, DPR states that an application containing an active ingredient that is under reevaluation over concerns regarding exposure to wildlife would not be precluded under this notice as an expanded use is if the product is labeled solely for indoor use, with no potential wildlife exposure.

DPR also acknowledges that a pest management or public health need could arise during a reevaluation that would support the issuance of an Emergency Exemption request under Section 18 of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). In those cases, with regard to the potential applicability of Notice 2018-1, DPR states that it “will assess the request by relying on currently available information and risk mitigation strategies.”


DPR’s reevaluation process can take years to complete, so not only are pending affected submissions for products containing the active ingredients at issue effectively frozen, but future submissions for active ingredients newly entering the reevaluation process could be halted potentially for lengthy periods of time, despite the fact that DPR may ultimately determine that any identified “expanded uses” do not cause a significant adverse environmental impact. It is an initiative that many in industry are monitoring closely.