Neonicotinoids

Back to Reevaluation Program

Image of apiary training sponsored by DPR, Parlier, CA. June 2014

 Apiary training sponsored by DPR,
Parlier, CA June 2014

Neonicotinoid Reevaluation Progress and Protecting Bee Health

The California Department of Pesticide Regulation (DPR) is at the national forefront of the effort to protect bee health, taking proactive steps and a scientific approach to address concerns about the impact of pesticides on pollinator health. One such step includes the reevaluation of certain pesticide products containing the nitroguanidine-substituted neonicotinoid active ingredients, imidacloprid, thiamethoxam, clothianidin, and dinotefuran. As a result of the reevaluation, which included issuance of a Neonicotinoid Risk Determination, DPR determined that additional mitigation measures are needed to protect pollinators from the use of neonicotinoids in agricultural crops. DPR drafted a mitigation proposal in the form of proposed regulations. In August 2020, DPR held neonicotinoid public feedback webinars to share information, answer questions, and receive feedback from registrants and other stakeholders on draft proposed mitigation for the protection of pollinators. DPR accepted comments on the draft proposal for 80 days after the webinars and received over 9000 comments. After careful evaluation of all comments received, DPR revised the proposed mitigation where appropriate and is now proposing regulations necessary to protect pollinator health, in accordance with Food and Agricultural Code section 12838.

Proposed Regulations and Additional Information

DPR published a Notice of Proposed Regulatory Action on February 25, 2022, at which time a sixty-day public comment period began. This comment period will end at 5:00 p.m. on April 26, 2022. A public hearing is scheduled for 9:30 AM on April 25, 2022 to receive oral or written comments regarding the proposed regulations. For more information on how to submit comments or how to attend the hearing, please review the Notice of Proposed Regulatory Action on DPR's Webpage for the proposed regulations. Additional documents associated with the proposed regulations are available on DPR's Webpage for the proposed regulations.

Background on the Reevaluation

In 2009, DPR placed certain pesticide products containing the neonicotinoid active ingredients, imidacloprid, thiamethoxam, clothianidin, and dinotefuran, into reevaluation. The reevaluation was initiated based on imidacloprid adverse effects data. These studies indicated a possible hazard to pollinators with two findings: high levels of imidacloprid residue in leaves and blossoms of treated plants and increases in residue levels over time. Thiamethoxam, dinotefuran, and clothianidin are in the same chemical family as imidacloprid, known as the nitroguanidine insecticide class of neonicotinoids, and have similar properties and characteristics.

DPR partnered with U.S. Environmental Protection Agency (U.S. EPA) and Pest Management Regulatory Agency (PMRA) Health Canada to assess risks to honey bees from the use of pesticides containing the neonicotinoid active ingredients. The agencies worked together to ensure that the required studies, and methods and procedures used to conduct studies on the effects of neonicotinoids provided useful and reliable information across the board to all three agencies for use in guiding their regulatory actions. DPR played a lead role in the development of the tiered honey bee risk assessment process in collaboration with the U.S. EPA, PMRA Health Canada, and the 2011 SETAC Pellston Workshop on Pesticide Risk Assessment for Pollinators.

DPR required comprehensive pollinator data as a part of its reevaluation. Registrants submitted numerous studies, which DPR evaluated to identify risks to pollinators. In July 2018, DPR published the California Neonicotinoid Risk Determination. On January 2019, DPR published an Addendum to the July 2018 California Neonicotinoid Risk Determination after receiving additional information and in an effort to report the most accurate information possible.

Following the publication of the Risk Determination and Addendum, DPR met with stakeholders to learn about commodity cultivation practices and neonicotinoid use patterns in the field while also meeting with registrants to discuss potential mitigation strategies.

For more information on the Neonicotinoid Reevaluation, visit the Reevaluation Program page to view the current semiannual report summarizing reevaluation status.

Other Information and Proactive Actions to Protect Bee Health


For content questions, contact:
Brittanie Clendenin
1001 I Street, P. O. Box 4015
Sacramento, CA 95812-4015
Phone: (916) 324-3896
E-mail: Brittanie.clendenin@cdpr.ca.gov