An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Pyrethrins and Pyrethroids Reregistration and Labeling

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.

This page includes information on reregistration and risk mitigation for pyrethrins, pyrethroid, and synergist. View overview information and current regulatory activities for pyrethrins and pyrethroids.

On this page:


Ten of the pyrethrins, pyrethroids, and synergists were registered before November 1, 1984, and therefore were subject to reregistration, but will be evaluated in the registration review process. In 2008, EPA completed Reregistration Eligibility Decisions (REDs) for these 10 individual pesticides:

The remaining pyrethroids, registered later, were not subject to reregistration.

Through the reregistration program, we reassessed the human health and ecological effects of older pesticides and required mitigation to address risks of concern. 

EPA’s REDs, RED Fact Sheets, Related Information, and Links to Dockets

Chemical Name/Case Name Docket ID Status Decisions Fact Sheets
Allethrin stereoisomers case 0437 EPA-HQ-OPP-2006-0986 Amended RED signed (05/2009)
RED signed (06/2007)
Amended RED (PDF)(172 pp, 1.24 MB)
RED (PDF)(167 pp, 3.1 MB)
Cypermethrin case 2130 EPA-HQ-OPP-2009-0592
Revised RED signed (01/2008)
RED signed (06/2006)
Revised RED (PDF)113 pp, 3.4 MB)
RED (PDF)(117 pp, 1.4 MB)
MGK-264 case 2430 EPA-HQ-OPP-2010-0014
RED signed (06/2006) RED (PDF)(81 pp, 937 K)  
Permethrin case 2510 EPA-HQ-OPP-2010-0014
Revised RED signed (05/2009)

Amended RED signed (12/2007)

RED signed (04/2006)
Revised RED (PDF)(200 pp, 951 K)
Amended RED (PDF)(202 pp, 1.7 MB)
RED (PDF)(195 pp, 3.2 MB)
Facts (PDF)(12 pp, 89 K, About PDF)
Piperonyl butoxide case 2525 EPA-HQ-OPP-2010-0014
RED signed (06/2006) RED (PDF)(111 pp, 1.1 MB)  
Pyrethrins case 2580 EPA-HQ-OPP-2010-0014
RED signed (06/2006) RED (PDF)(108 pp, 1.4 MB)  
Resmethrin case 0421 EPA-HQ-OPP-2010-0014
RED signed (06/2006) RED (PDF)(102 pp, 2 MB)  
Sumithrin (d-phenothrin) case 0426 EPA-HQ-OPP-2008-0140 RED signed (09/2008) RED (PDF)(54 pp, 437 K)  
Tau-fluvalinate case 2295 EPA-HQ-OPP-2005-0230 RED signed (09/2005) RED (PDF)(85 pp, 1.2 MB)  
Tetramethrin case 2660   Revised RED signed (04/2010)
RED signed (06/2008)
Revised RED(PDF)(83 pp, 577 K)
RED (PDF)(57 pp, 793 K)

Following the REDs, several subsequent label mitigation efforts were undertaken for improved product safety and stewardship, as well as label clarity.

Label Changes to Reduce Risk

Ecological Risk Mitigation

Pyrethroids are highly toxic to aquatic organisms. Because the pyrethroids can accumulate in sediments, risk to sediment-dwelling organisms is an area of particular concern.

Recent water quality monitoring efforts in California have identified pyrethroids in sediments of water bodies adjacent to residential/urban areas. These monitoring data, coupled with additional pyrethroid-specific data submitted to EPA, highlight existing concerns regarding residential uses of pyrethroid pesticide products and movement into non-target areas through runoff or spray drift that may occur during applications.

To reduce exposure to water bodies from non-agricultural and agricultural uses of pyrethroids, we deployed the following labeling initiatives.

Environmental Hazard and General Labeling for Pyrethroid and Synergized Pyrethrins Non-agricultural Outdoor Products – Revised February 2013 – To reduce exposure from residential uses of pyrethroids and pyrethrins products, we implemented a 2009 labeling initiative, with minor revisions in 2013. This initiative required revised environmental hazard statements and general directions for use for pyrethroid and pyrethrins pesticide products used in non-agricultural outdoor settings. The label statements spell out good stewardship and best-management practices and clarify how these types of products are intended to be used.

These label statements serve to reduce the potential for runoff and drift to water bodies that can result from applications of pyrethroid end-use products in residential, commercial, institutional, and industrial areas, applied by both professional pesticide control operators and residential consumers.

Records of Environmental Hazard Labeling Correspondence

We have received letters related to environmental hazard labeling requirements from a variety of interested parties. The following are the letters and responses on this issue.

The letter from the California Department of Pesticide Regulation describes regulations the state is proposing related to use of pesticide products containing pyrethroids and asks some questions related to implementation of label requirement EPA imposed in 2009. See the letter from CA DPR and EPA’s response.

The Ohio Pest Management Association provided comments on the 2009 labeling initiative in regard to effect of those changes on potential pest control success. The letter to the Ohio Pest Management Association responds to comments from that organization on EPA’s 2009 pyrethroid label initiative, providing clarification related to their issues. See the letter from OPMA and EPA's response.

The letter from the National Pest Management Association provides comments and questions related to several topics in the 2009 pyrethroid labeling changes. One issue relates to the use of pyrethroids against pests such as stink bugs in residential settings. EPA’s response clarifies mandatory versus advisory language, responsibility for implementing certain instructions, and the role of these changes in preventing or reducing pesticide runoff. See the letter from NPMA and EPA's response.

The Association of Structural Pest Control Regulatory Officials commented on the 2009 pyrethroid labeling initiative, in particular related to placement of language in the environmental hazards section of the label, spot treatment, foundation type, impervious surfaces, application to windows, doors, and eaves, treatment of vertical surfaces, “do not water to runoff” for granules, preconstruction termiticide treatments, limitation within 25 feet of aquatic habitat, and wind speed at nozzle height. The EPA response discusses future plans for working on issues related to these label changes.

Pyrethroid Spray Drift Initiative 

In the reregistration process for permethrin and cypermethrin, we determined that the existing spray drift language for pyrethroid agricultural products needed to be updated to comply with FIFRA. Because of similarities in use patterns and concern for exposure to aquatic resources, the same changes are appropriate for all pyrethroid products used on agricultural crops. In a letter from the Agency dated February 21, 2008, all pyrethroid registrants with affected products were instructed to incorporate the revised spray drift language onto their agricultural labels, and submit the amended labels to the Agency.

Total Release Foggers

Total release foggers, also known as "bug bombs," are pesticide products containing aerosol propellants that release their contents at once to fumigate an area. Pyrethrins, pyrethroids and synergists are often the active ingredients in these products.

Total release foggers are consumer products primarily marketed for use in homes and apartments for control of pests such as roaches or fleas. The risks and appropriate precautions for use of this type of product are described in our Total Release Foggers fact sheet.

Fogger Labeling Changes to Improve Residential Safety

We required the following labeling changes for indoor total release fogger products distributed or sold by the registrant after September 30, 2012.

  • Total release fogger labels must be written in plain language with clear headings.
  • The new labels must incorporate pictograms to illustrate the following list of restrictions and directions for use:
    • Do not use multiple canisters in a room.
    • Do not use in small confined areas.
    • Unplug and turn off ignition sources.
    • No flames or pilot lights.
    • Remove or cover exposed food.
    • Air out the room before entering.
  • Instructions to vacate upon use and air out upon return must be very clear.
  • Door hang-tags must be provided to inform others to stay out of treated areas.

The Agency has created a list of approved pictograms available for use by all total release fogger registrants

EPA sent a letter notifying pyrethrin and pyrethroid registrants of these labeling changes on March 23, 2010. The Agency sent a second letter notifying pyrethrin and pyrethroid registrants of the list of approved pictograms on July 6, 2011. 

Our 2010 total release fogger labeling improvements are consistent with recommendations from Washington state (PDF) (18 pp, 226.9 K, About PDFExitand a 2008 Center for Disease Control report entitled Illnesses and Injuries Related to Total Release Foggers, and are expected to address concerns raised by a 2009 petition from the New York City Department of Health to reclassify TRFs as restricted use pesticides. EPA’s response to the petition explains the Agency’s careful analysis of the petition and incident reports going back to the 1990s. The Agency concluded that reclassification is inappropriate and would unnecessarily remove these cost effective pest control tools from the residential market. View the petition and EPA's response. Search EPA Archive

Records of Fogger Meetings

These documents are meeting minutes relevant to the total release fogger labeling improvements effort: Search EPA Archive

  • October 8, 2009 Meeting with S. C. Johnson Company 
  • September 23, 2009 Meeting with United Industries 
  • May 12, 2009 Meeting at EPA with Total Release Fogger Registrants 
  • April 23, 2009, Meeting with Daniel Kass, Assistant Commissioner, NYC Department of Health and Mental Hygiene