DPR Releases Findings from Independent Fumigant Alternatives Study, Focused on Structural Use of Sulfuryl Fluoride

WHAT YOU NEED TO KNOW:

DPR has released findings from an independent study on alternatives to sulfuryl fluoride, a pesticide used to fumigate buildings for pests such as termites. The study found that while localized treatments are often effective, few alternative options for whole-structure fumigation exist, signaling a need for further research.

SACRAMENTO—The California Department of Pesticide Regulation (DPR) today released the structural fumigation component of a multi-part independent scientific study evaluating alternatives to fumigant pesticides. The study, conducted by the California Council on Science and Technology (CCST), is part of DPR’s work to advance Sustainable Pest Management (SPM) statewide by identifying safer, effective and practical alternatives to high-risk pesticides.

CCST evaluated ten alternatives to sulfuryl fluoride, which is the only federally approved pesticide used to manage pests like termites or beetles for whole-structure fumigation. The study found that both chemical and non-chemical localized treatments are effective and widely used in California. However, CCST concluded that few viable alternatives are available for whole-structure fumigation.

“An important component of our work to foster sustainable pest management statewide includes identifying effective alternatives, opportunities to support broader adoption, and gaps where additional research is needed,” said DPR Director Karen Morrison. “CCST’s findings will help us focus future research priorities, evaluation, and regulatory actions.”

As part of its findings, the CCST study also identifies barriers to expanding the use of currently available alternatives, including risk tolerance for pests, cost considerations, and regulatory factors. CCST concluded that existing research does not yet fully compare the costs and relative effectiveness of alternatives with whole-structure fumigation.

Sulfuryl fluoride is currently one of the active pesticides DPR is evaluating, as outlined in the department’s Continuous Evaluation and Mitigation priorities. Last year, DPR conducted an observational study of residential homes following sulfuryl fluoride fumigation and is initiating a follow-up observational study in 2026 as part of broader work to continuously evaluate pesticides to protect people and the environment.

Funded by the California Budget Act of 2023–24, DPR commissioned CCST to conduct the fumigant alternatives study to support implementation of the Sustainable Pest Management Roadmap. The first set of findings, released in early 2025, focused on the soil fumigants 1,3-dichloropropene (1,3-D) and chloropicrin. DPR anticipates the final reports on pre-plant soil fumigants and post-harvest commodity fumigants in early 2026.

Phase 2 Report on Structural Fumigation with Sulfuryl Fluoride