DPR Releases Draft Annual Report on 1,3-D Non-Occupational Bystander Regulation (DPR 22-005)

The California Department of Pesticide Regulation (DPR) today released the draft first annual report examining the effectiveness of its 2024 regulation in mitigating short-term acute and long-term cancer risks to residents and other non-occupational bystanders from 1,3-dichloropropene (1,3-D).

Public comments will be accepted on the draft report as part of a 45-day comment period, open Oct. 1 through November 14.

To comment on the report, go to DPR’s online portal.

The 2024 regulation reduces 1,3-D air concentrations by implementing new fumigation methods as well as requiring new setbacks between occupied structures and fields being treated, applying limits on application rates and acreage, and requiring higher soil-moisture levels for fumigations.

The regulation requires DPR to issue an annual report with an evaluation of 1,3-D use data and monitoring data for the previous calendar year, specifically assessing the concentrations of 1,3-D in the highest-use townships (a 6×6-mile area). DPR must also model any concentrations over the regulatory thresholds to understand if mitigation measures are working as anticipated and determine if any additional actions are warranted.

DPR’s analyses of 1,3-D use and air monitoring data indicate that current regulatory measures are functioning as intended. There is no evidence at this time to suggest that additional regulatory actions are necessary.

For more on 1,3-D, see DPR’s Active Ingredient page.