Information on Chlorpyrifos
Find information on the registration status, continuous evaluation and mitigation measures in California to regulate this active ingredient. An active ingredient is the chemical that makes a pesticide work on a target pest.
Active Ingredient: Chlorpyrifos
Type of Pesticide: Insecticide
California Registration: Yes
EPA Registration: Yes
Fumigant: No
California Restricted Material: Yes
Toxic Air Contaminant (TAC): Yes
Volatile Organic Compound (VOC): Yes
Potential Groundwater Contaminant: No
Reevaluation Status: Concluded
Chemical Class: Organophosphate
DPR Chemical Code: 253
Recent Reports and Announcements
- Chlorpyrifos (Dursban®, Lorsban®) Dietary Exposure Assessment
- Correlating Agricultural Use with Ambient Air Concentrations of Chlorpyrifos And Chlorpyrifos-Oxon During the Period of 2011-2014
- DPR Awards $1.34 Million for Alternatives to Chlorpyrifos Research Grants
- Agreement Reached to End Sale of Chlorpyrifos in California by February 2020
- Alternatives to Chlorpyrifos Work Group Announced
- California Acts to Prohibit Chlorpyrifos Pesticide
- DPR Recommends Interim Restrictions on Use of Chlorpyrifos
- Proposal to List Chlorpyrifos as a Toxic Air Contaminant Opens for Public Comment
- State Proposes Restriction on Availability of Chlorpyrifos
- Estimation of Chlorpyrifos Horizontal Deposition and Air Concentrations for California Use Scenarios
- Towards Safer and More Sustainable Alternatives to Chlorpyrifos: An Action Plan for California
Risk Evaluation and Mitigation Documents
- October 2019 - Cancellation of Chlorpyrifos Products Final Notice of Use and Sale Conditions for Chlorpyrifos Products - English pdf
- August 2019 - Consultation on Proposed Cancellation of Chlorpyrifos Products - Response to Comments Received from the California Agricultural Commissioners and Sealers Association for Proposed Cancellation - English pdf
- August 2019 - Consultation on Proposed Cancellation of Chlorpyrifos Products - Response to Comments Received from the California Department of Food and Agriculture for Proposed Cancellation - English pdf
- July 2019 - Consultation on Proposed Cancellation of Chlorpyrifos Products - California Department of Food and Agriculture Comments on Proposed Cancellation - English pdf
- June 2019 - Chlorpyrifos Response to Comments Received for Proposed Risk Management Directive - English pdf
- July 2019 - Consultation on Proposed Cancellation of Chlorpyrifos Products - California Agricultural Commissioners and Sealers Association Comments on Proposed Cancellation - English pdf
- May 2019 - Risk Management Directive for Chlorpyrifos - English pdf
- April 2019 - California Air Resources Board Comments on Proposed Risk Management Directive Chlorpyrifos - English pdf
- May 2019 - California Air Pollution Control Officers Association Comments on Proposed Risk Management Directive Chlorpyrifos - English pdf
- April 2019 - California Department of Food & Agriculture Comments on Proposed Risk Management Directive Chlorpyrifos - English pdf
- April 2019 - Office of Environmental Health Hazard Assessment Comments on Proposed Risk Management Directive Chlorpyrifos - English pdf
- November 2018 - ENF 2018-22 - Updates to Volume 3, Restricted Materials and Permitting, Pesticide Use Enforcement Program
- November 2018 - Revised Interim Permit Conditions Chlorpyrifos - English pdf
- August 2018 - Chlorpyrifos Scientific Review Panel's Findings - English pdf
- August 2018 - Director’s Proposed Determination Concerning Chlorpyrifos as a Toxic Air Contaminant - English pdf
- July 2018 - Chlorpyrifos Executive Summary - English pdf
- July 2018 - Final Toxic Air Contaminant Evaluation of Chlorpyrifos (Complete Document) - English pdf
- July 2018 - Final Toxic Air Contaminant Evaluation of Chlorpyrifos (Evaluation Only) - English pdf
- July 2018 - Appendix 1 - Summary of Toxicology for Chlorpyrifos - English pdf
- July 2018 - Appendix 2 - Exposure Estimates and Margins of Exposure for Developmental Neurotoxicity - English pdf
- July 2018 - Appendix 3 - Revised Margins of Exposure for Acetylcholinesterase Inhibition - English pdf
- July 2018 - Appendix 4 - Andrews and Patterson, 2000 - English pdf
- July 2018 - Appendix 5 - Mechanistic Studies of Chlorpyrifos Related Neurodevelopmental Effects - English pdf
- July 2018 - Appendix 6 - December 2017 Draft Evaluation of Chlorpyrifos as a Toxic Air Contaminant - English pdf
- June 2018 - Scientific Review Panel Meeting Presentation: Consideration of Addendum to Draft Evaluation of Chlorpyrifos as a Toxic Air Contaminant - English pdf
- June 2018 - Chlorpyrifos Cover Letter to Scientific Review Panel - English pdf
- January 2018 - Chlorpyrifos Responses to OEHHA Findings - English pdf
- December 2017 - Scientific Review Panel Meeting Presentation: Overview of Draft Evaluation of Chlorpyrifos as a Toxic Air Contaminant (PDF) - English pdf
- December 2017 - Office of Environmental Health Hazard Assessment Findings on the Health Effects of Chlorpyrifos as a Candidate Toxic Air Contaminant - English pdf
- December 2017 - Draft Evaluation of Chlorpyrifos as a Toxic Air Contaminant for the Scientific Review Panel - English pdf
- December 2017 - Chlorpyrifos Cover Letter to Scientific Review Panel - English pdf
- December 2017 - Chlorpyrifos Charge Questions for the Scientific Review Panel - English pdf
- December 2017 - Chlorpyrifos Responses to Technical Comments by the Public - English pdf
- December 2017 - Chlorpyrifos Responses to Comments by Dow AgroSciences LLC - English pdf
- October 2017 - ENF 2017-23 - Updates to Volume 3, Restricted Materials and Permitting, Pesticide Use Enforcement Program Standards Compendium, Appendix O: Chlorpyrifos Interim Recommended Permit Conditions
- October 2017 - Evaluation and Options for Interim Mitigation Measures to Reduce Acute Chlorpyrifos Exposure to Bystanders - English pdf
- August 2017 - Draft Evaluation of Chlorpyrifos as a Toxic Air Contaminant - English pdf
- August 2017 - Chlorpyrifos Responses to Comments by the California Air Resources Board - English pdf
- August 2017 - Chlorpyrifos Responses to Comments by the Office of Environmental Health Hazard Assessment - English pdf
- August 2017 - Chlorpyrifos Responses to Comments on Toxicology by Dow AgroSciences LLC - English pdf
- August 2017 - Chlorpyrifos Responses to Comments on Exposure by Dow AgroSciences LLC - English pdf
- August 2017 - Revised: Estimation of Chlorpyrifos Horizontal Deposition and Air Concentrations for California Use Scenarios - English pdf
- August 2017 - Cases Reported to the Pesticide Illness Surveillance Program and Evaluated as Associated with Exposure to Chlorpyrifos, Alone or in Combination with Other Products, 2004-2014 - English pdf
- August 2017 - Directive for Interim Mitigation Measures to Address Health Risk from Chlorpyrifos - English pdf
- December 2015 - Chlorpyrifos Draft Risk Characterization Document - English pdf
- December 2015 - Estimation of Chlorpyrifos Horizontal Deposition and Air Concentrations for California Use Scenarios
- July 2015 - ENF 2015-09 - Interim Recommended Permit Conditions for Chlorpyrifos used to Produce and Agricultural Commodity: Addition to Compendium Volume 3, Restricted Material and Permitting
- February 2005 - ENF 2005-008 - Chlorpyrifos Phase Out Questions and Answers
Historic Documents
- September 2020 – Presentation on Chlorpyrifos Workgroup Updates
- January 2019 – Presentation on Interim Recommended Permit Conditions for Chlorpyrifos
- September 2018 – Pesticide Registration and Evaluation Committee Meeting Agenda
- September 2018 – Pesticide Registration and Evaluation Committee Meeting Minutes
- September 2018 – Presentation on Chlorpyrifos Update
- September 2018 – Presentation on Chlorpyrifos Updates
- June 2018 - Draft Evaluation of Chlorpyrifos as a Toxic Air Contaminant (Addendum to December 2017 Draft Evaluation)
- October 2017 - Revised Interim Permit Conditions
- September 2017 – Pesticide Registration and Evaluation Committee Meeting Agenda
- September 2017 – Pesticide Registration and Evaluation Committee Meeting Minutes
- September 2017 – Presentations on the Chlorpyrifos Draft Risk Assessment
- September 2017 – California's Toxic Air Contaminant Program for Pesticides
- September 2017 – Draft Evaluation of Chlorpyrifos as a Toxic Air Contaminant
- September 2017 – Directive for Interim Mitigation Measures to Address Health Risks from Chlorpyrifos
- August 2017 – Report for Pesticide Application Air Monitoring for Chlorpyrifos and Chlorpyrifos-Oxon in San Joaquin County in July 2015
- December 2016 – Report for Pesticide Application Site Monitoring for Chlorpyrifos and Chlorpyrifos-Oxon in Imperial County in October 2014
- July 2015 – Designating Chlorpyrifos as a Restricted Material
- July 2015 – Interim Permit Conditions
- March 2015 - Agricultural Pest Control Advisory Committee Meeting Agenda
- March 2015 - Chlorpyrifos Update
- March 2015 - Agricultural Pest Control Advisory Committee Meeting Minutes
- November 2014 - Pest Management Advisory Committee Meeting Agenda
- November 2014 - Proposed Regulation to Designate Chlorpyrifos a Restricted Material
- September 2014 - Agricultural Pest Control Advisory Committee Meeting Agenda
- September 2014 - Chlorpyrifos Update
- August 2014 - Pesticide Registration and Evaluation Committee Agenda
- August 2014 - Chlorpyrifos Update
- August 2014 - Pesticide Registration and Evaluation Committee Meeting Minutes
- March 2013 – Lompoc Monitoring Report
- August 2011 – Comments On U.S. EPA's Preliminary Risk Assessment For Chlorpyrifos: With A Focus On Exposure Assessment
- May 2010 – Comparison of Initial Deposition and Residue Dissipation of Chlorpyrifos Using Conventional Flat Fan Nozzles vs. Hypro® TwinCap™ Nozzles Fitted with Ultra-Lo Drift Spray Tips
- January 2009 - Pesticide Registration and Evaluation Committee Agenda
- January 2009 - Status of Chlorpyrifos and Diazinon Reevaluations
- January 2009 - Pesticide Registration and Evaluation Committee Meeting Minutes
- September 2007 – Results from Sample Collection in Tulare County for A Suspected Organophosphate Exposure Event
- September 2007 – Project 0703 - Tulare County Chlorpyrifos Restricted Entry Interval Violation in Oranges
- September 2007 – Project 0704 - WHS Involvement In Priority Investigation 41-Tul-07: Chlorpyrifos Drift Investigation, Tulare County
- September 2007 – Project 0706 - Worker Health and Safety's Involvement In: Chlorpyrifos Drift Investigation In Fresno County
- May 2007 - Pest Management Advisory Committee Meeting Agenda
- February 2005 – Chlorpyrifos Field Spike Degradation Study, Project #0403
- April 2004 – Forensic Review and Sampling of PPE/Respiratory Protective Equipment Associated with Priority Investigation 3-RIV-04
- March 2004 – Forensic Review and Sampling of PPE/Respiratory Protective Equipment Associated with Priority Investigation 3-RIV-04
- October 2002 – Response to Comments from Dow AgroSciences LLC on the Draft Chlorpyrifos Risk Characterization Document by the California Department of Pesticide Regulation (Exposure Assessment Section)
- October 2001 – WH&S Branch Activities and Results of Analyses Related to the Investigation of 22-TUL-00 (Project 0001)
- WH&S Branch Activities and Results of Analyses Related to the Investigation of 43-FRE-99 (Project 9903)
- October 2001 – WH&S Branch Activities and Results of Analyses Related to the Investigation of Priority Illness Episode 45-TUL-00 (Project 0002)
- July 1999 – Chlorpyrifos Odor Provoking the Onset of Clinical Symptoms
- January 1999 – Oral and Dermal Absorption of Chlorpyrifos: A Human Volunteer Study
- April 1998 – Report for the Application and Ambient Air monitoring of Chlorpyrifos in Tulare County During Spring/Summer, 1996 (Appendices)
- February 1998 – Contact Dermatitis in California Nursery Workers: Part II. Pilot Field Study
- June 1993 – Exposure Assessment Document
- February 1993 – Aerial Movement and Deposition of Diazinon, Chlorpyrifos, and Ethyl Parathion (Executive Summary)
- May 1992 – Dietary Exposure Assessment Document
- December 1991 – 1989 Probe Study to Determine the Exposure of Aerial Application Flaggers to Organophosphate Pesticides Via Urinary Metabolite Monitoring
- August 1991 – Determination of Dermal Absorption of Chlorpyrifos in Humans
- April 1991 – Structural Chemical Exposure Studies Provide Human Metabolism and Urine Clearance Data for Chlorpyrifos, Dimethoate and Malathion
- March 1991 – Measuring Potential Dermal Transfer of Surface Pesticide Residue Generated from Indoor Fogger Use: Using the CDFA Roller Method, Interim Report II
- March 1991 – Situational Chemical Exposure Studies Provide Human Metabolism and Urine Clearance Data for Chlorpyrifos, Dimethoate, and Malathion
- May 1990 – Measuring Potential Dermal Transfer of Surface Pesticide Residue Generated from Indoor Fogger Use: An Interim Report (Chemosphere 20, (3/4), 349-360, 1990)
- January 1990 – Human Illnesses/Injuries Reported by Physicians in California Involving Indoor Exposure to Pesticides Containing Chlorpyrifos, DDVP and/or Propoxur 1983-1986
- July 1986 – Dissipation of Dislodgeable Foliar Residue for Chlorpyrifos and Dichlorvos Treated Lawn: Implication for Safe Reentry (Bull Environ Contam & Toxicol 37, 33-40, 1986)
- December 1985 – Monterey County Residential Air Monitoring
- November 1984 – Dissipation of Dislodgeable Residue of Chlorpyrifos and DDVP on Turf
- July 1984 – Degradation of Dislodgeable Residues of Chlorpyrifos and Diazinon on Turf - A Preliminary Survey