Sulfuryl Fluoride
Related Information
Basic Information
Sulfuryl fluoride is a colorless and odorless gas that is a structural and commodity fumigant used to control a wide variety of pests, including termites, powder post beetles, old house borers, bedbugs, carpet beetles, moths, cockroaches, rats and mice. Sulfuryl fluoride is a restricted use pesticide (RUP), with products registered for use in buildings, construction materials, furnishings, vehicles, dwellings, and food commodities (e.g., grains, dried fruit, dried beans). Sulfuryl fluoride is a replacement for methyl bromide and the only structural fumigant with residential uses.
Since sulfuryl fluoride is odorless and colorless, chloropicrin is required to be used in residential structural fumigations as a warning agent to detect the presence of sulfuryl fluoride. Chloropicrin causes smarting of the eyes, tears, discomfort, and has a pungent odor. Chloropicrin is released into the fumigated space prior to the introduction of sulfuryl fluoride.
Registration Review Schedule
Sulfuryl fluoride is currently undergoing registration review, a program that re-evaluates all pesticides on a 15-year cycle. In December 2009, EPA completed the final work plan and in September 2010, EPA issued the data call-in. In May 2021, EPA released three draft risk assessments. Once the risk assessments for all uses of sulfuryl fluoride are issued for public comment, the Agency will issue the proposed interim decision, to address any human health and ecological risks identified in the risk assessments. All registration review documents can be found in the sulfuryl fluoride registration review docket EPA-HQ-OPP-2009-0136 at www.regulations.gov.
Office of Inspector General Response
In December 2016, EPA's Office of Inspector General (OIG) issued a report, Additional Measures Can Be Taken to Prevent Deaths and Serious Injuries From Residential Fumigations, that assessed additional safety measures that could be taken to prevent serious injuries from use of sulfuryl fluoride during residential fumigation. The OIG Report recommended that EPA make changes to how this pesticide can be used and complete an assessment of the clearance devices used to determine safe reentry levels in homes after fumigation. To address the recommendations in the OIG Report, EPA completed an assessment of the devices and an assessment for residential post application exposure.
In May 2021, EPA released those assessments and proposed mitigation in the Draft Interim Re-Entry Mitigation Measures, which published for a 60-day comment period on May 25, 2021, a period which was extended for an additional 60 days, to close on September 23, 2021. After considering the public comments and meeting with stakeholders, the Agency published the early mitigation for sulfuryl products with the issuance of the Sulfuryl Fluoride Revised Mitigation and Response to Comments on the Draft Interim Re-entry Mitigation Measures Memorandum in June 2023. EPA amended the mitigation measures by adding clarification on the clearance devices listed on the website in May 2024, and published the Updated Label Language for the Sulfuryl Fluoride Revised Mitigation and Response to Comments on the Draft Interim Re-Entry Mitigation Measures Memorandum. This interim mitigation finalizes risk mitigation measures ahead of the typical mitigation phase of Registration Review in response to the OIG Report. In this decision, EPA lists the following label requirements to ensure safe use as a structural fumigant in residential use sites:
- Clearly post warning signs to prevent admittance to fumigation tents during fumigation;
- Site-specific fumigation logs for residential fumigations;
- Additional registrant sponsored application stewardship training;
- Remove references to “approved” clearance devices from product labels and refer users to the EPA website, which will list the portable clearance devices determined to be effective, according to the EPA’s performance criteria; and
- Longer active and passive aeration times for Aeration Procedures 1 and 2.
The scope of this early mitigation focused on the use of sulfuryl fluoride as a structural fumigant in residential use sites. For all sulfuryl fluoride products registered for residential use, amended labels were submitted with the revised label language, which the Agency approved on July 11, 2024. Existing stocks of sulfuryl fluoride products bearing previously-approved labels can be distributed and sold for 12 months from that date.
Notwithstanding this action, sulfuryl fluoride is still undergoing EPA' s re-evaluation process, Registration Review, wherein all uses of sulfuryl fluoride are being assessed.