DPR 24-001 Health Risk Mitigation for 1,3-Dichloropropene
Back to Proposed and Recently Adopted Regulations
Sign-up to receive Notices of Proposed Regulatory Action via e-mail.
DPR 24-001 Health Risk Mitigation for 1,3-Dichloropropene (Notice 11/15/24; Comment period closes 1/24/25)
DPR proposes to adopt Title 3, California Code of Regulations (3 CCR) section 6448.5 and amend sections 6000, 6448, 6448.2, 6448.4, 6624, and 6626. In summary, the proposed action restricts the use of 1,3-dichloropropene (1,3-D) to mitigate the potential 40-year working lifetime cancer risk to occupational bystanders. The proposed action establishes buffer zone distances (distances from the edge of a treated area where certain activities are restricted) and requires DPR to include an evaluation in the 1,3-D Annual Report of whether the 1,3-D air concentration in any township exceeds the acceptable level of 0.21 part per billion and to develop appropriate measures to reduce exposures if target air concentration levels are exceeded. DPR also proposes to repeal the document “1,3-Dichloropropene Field Fumigation Requirements, Est January 1, 2024,” and adopt the document “1,3-Dichloropropene Field Fumigation Requirements, Rev. January 1, 2026,” which is incorporated by reference in existing sections 6448, 6448.2, 6624, and 6626. A copy of this document is posted below.
DPR will hold the three in-person public hearings and one virtual public hearing to receive oral and/or written comments regarding the proposed action. A presentation on the proposed regulations will be given prior to the start of each in-person hearing at 5:45 p.m. and prior to the virtual hearing at 9:45 a.m. The in-person hearing will commence at 6:00 p.m. and the virtual hearing will commence at 10:00 a.m. Details are listed below.
DATE: Wednesday, January 8, 2025
TIME: 6:00-8:00 p.m.
PLACE: Visalia Veteran's Memorial
609 W Center Ave.
Visalia, California 93291
DATE: Friday, January 10, 2025
TIME: 10:00 a.m.
PLACE: Zoom (Virtual)
Webinar ID: 845 7679 6884
Direct link to join the meeting from a web browser or Zoom client
One tap to join from a mobile phone: +16699009128,,84576796884#
Or call from a landline: +1 669 900 9128 – and enter the Webinar ID (above) when prompted
DATE: Thursday, January 16, 2025
TIME: 6:00-8:00 p.m.
PLACE: National Steinbeck Center
1 Main Street
Salinas, California 93901
DATE: Tuesday, January 21, 2025
TIME: 6:00-8:00 p.m.
PLACE: Chico Women's Club
592 East 3rd Street
Chico, California 95928
- Notice of Proposed Regulatory Action, PDF (Aviso de Acción Reglamentaria Propuesta)
- Proposed Text, PDF
- Initial Statement of Reasons, PDF
- Economic and Fiscal Impact Statement (Form 399), PDF
- Documents Relied Upon
- Brown, Colin. 2019. “HYDRUS-simulated flux estimates of 1,3-dichloropropene maximum period-averaged flux and emission ratio for approved application methods,” Department of Pesticide Regulation Report, October 17, 2019.
- Brown, Colin. 2022. “Updates to HYDRUS-simulated flux estimates of 1,3-dichloropropene maximum period-averaged flux and emission ratios,” Department of Pesticide Regulation Report, September 22, 2022.
- DPR. 2016a. “Response to comments by OEHHA on DPR-HHAB’s draft 1,3-dichloropropene risk assessment document (dated August 31, 2015),” August 6, 2016. Department of Pesticide Regulation.
- DPR. 2016b. “Response to comments by US EPA on DPR-HHAB’s draft 1,3-Dichloropropene Risk Characterization Document dated August 31, 2015,” September 8, 2016. Department of Pesticide Regulation.
- DPR. 2016c. “Responses to comments by Dr. Urmila P. Kodavanti on DPR-HHAB’s draft 1,3- Dichloropropene Risk Characterization Document dated Aug. 31, 2015.” September 8, 2016. Department of Pesticide Regulation.
- DPR. 2016d. “Responses to comments by Dr. Richard A. Fenske on DPR-HHAB’s draft 1,3- Dichloropropene Risk Characterization Document dated November 19, 2015.” September 8, 2016. Department of Pesticide Regulation.
- DPR. 2016e. “Responses to comments by Dr. Weisueh A. Chiu on DPR-HHAB’s draft 1,3- Dichloropropene Risk Characterization Document dated August 31, 2015.” September 14, 2016. Department of Pesticide Regulation.
- DPR. 2016f. “Response to comments by Dow AgroSciences on DPR-HHAB’s draft 1,3- Dichloropropene Risk Characterization Document dated Aug. 31, 2015.” November 8, 2016. Department of Pesticide Regulation.
- DPR. 2015b. “1,3-Dichloropropene Risk Characterization Document: Inhalation Exposure to Workers, Occupational and Residential Bystanders and the General Public,” December 31, 2015. Department of Pesticide Regulation.
- DPR. 2024a. “Review by the Toxic Air Contaminant Workgroup of Documents Related to the Draft 1,3-Dichloropropene Occupational Bystander Regulations, November 2024.” Department of Pesticide Regulation document.
- DPR. 2024b. “Agricultural Pest Control Advisory Committee Agenda, December 11, 2024.” Department of Pesticide Regulation.
- DPR. 2024c. “Pesticide Registration and Evaluation Committee Agenda, November 15, 2024.” Department of Pesticide Regulation.
- Henderson, Julie. 2024. “Risk Management Directive for Occupational Bystander Cancer Risk from 1,3-Dichloropropene (1,3-D),” Department of Pesticide Regulation Memorandum, March 6, 2024.
- Kandelous, Maziar. 2019. “A Comparison Between Field-Estimated and HYDRUS-Simulated Emission of 1,3-Dichloropropene From Agricultural Fields, October 17, 2019.” Department of Pesticide Regulation Report.
- Luo, Yuzhou. 2019a. “Evaluating AERMOD for Simulating Ambient Concentrations of 1,3-Dichloropropene, October 17, 2019.” Department of Pesticide Regulation Report.
- Luo, Yuzhou. 2019b. “AERFUM: An Integrated Air Dispersion Modeling System for Soil Fumigants, October 17, 2019.” Department of Pesticide Regulation Report.
- Luo, Yuzhou and Randy Segawa. 2024. “Modeling for Evaluating Occupational Bystander Cancer Risk From 1,3-Dichloropropene, August 29, 2024.” Department of Pesticide Regulation Report.
- Mace, Kevi., F. Ganjisaffar, S. Rabourn, and R. Goodhue. 2024a. “1,3-Dichloropropene Occupational Safety Regulation Economic Impact Report,” August 1, 2024. California Department of Food and Agriculture and University of California, Davis.
- Mace, Kevi. 2024b. “Acreage Treated With Non-TIF Methods and Estimated Annual Cost of Adding TIF Tarp,” August 8, 2024. California Department of Food and Agriculture memorandum.
- Mace, Kevi. 2024c. “Number of Farms Using 1,3-Dichloropropene-Updated,” August 1, 2024. California Department of Food and Agriculture memorandum.
- Marks, Teresa. 2016a. “Comments on the Draft Risk Management Directive for 1,3-Dichloropropene (1,3-D) and Responses” October 6, 2016. Department of Pesticide Regulation Letter.
- Marks, Teresa. 2016b. “Risk Management Directive and Mitigation Guidance for Cancer Risk from 1,3-Dichloropropene (1,3-D),” October 6, 2016. Department of Pesticide Regulation Memorandum.
- OEHHA. 2023. “Health-Based Recommendations to Mitigate Cancer Risk of Occupational Bystander Exposure to 1,3-Dichloropropene,” December 13, 2023. Office of Environmental Hazard Assessment memorandum.
- OEHHA. 2024a. “Update to the Health-Based Recommendations to Mitigate Cancer Risk of Occupational Bystander Exposure to 1,3-Dichloropropene,” June 11, 2024. Office of Environmental Hazard Assessment memorandum.
- OEHHA. 2024b. “Request for External Scientific Peer Review of the Scientific Basis of OEHHA Memorandum: “Update to the Health-Based Recommendations to Mitigate Cancer Risk of Occupational Bystander Exposure to 1,3-Dichloropropene and its associated documents,” September 20, 2024. Office of Environmental Hazard Assessment memorandum.
- OEHHA. 2024c. “Estimation of Lifetime Exposure for Occupational Bystanders When Regularly Working at the Edge of 1,3-Dichloropropene Treated Fields,” August 8, 2024. Office of Environmental Health Hazard Assessment Report.
- U.S. EPA. 2017. “Revisions to the Guideline on Air Quality Models: Enhancements to the AERMOD Dispersion Modeling System and Incorporation of Approaches To Address Ozone and Fine Particulate Matter.” U.S. Environmental Protection Agency. Federal Register, Vol. 82, No. 10, January 17, 2017.