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Registration Review of Pyrethrins and Pyrethroids

In 2019 and 2020, EPA published the following documents:

Ecological Risk Assessments and Mitigation

In late 2016, EPA released a draft ecological risk assessment for eight pyrethroids plus the pyrethrins and a risk management rationale for the remaining pyrethroids currently undergoing registration review.

The Agency assessed the pyrethroids and pyrethrins as a class rather than by individual chemical for the draft ecological risk assessment to increase efficiency and consistency in the risks assessed and to implement consistent risk mitigation.

To address potential risks of concern for terrestrial/aquatic invertebrates and fish described in the 2016 draft ecological risk assessments, EPA has determined that ecological risk mitigation to reduce spray drift, reduce runoff, and promote soil conservation practices for the entire class of pyrethrins and pyrethroids is necessary. Read the Ecological Risk Mitigation Proposal and the Revised Ecological Risk Mitigation for more detail.

List of Pyrethrins and Pyrethroids

Chemical Docket Number Status
Special  Docket for the Pyrethroids and Pyrethrins EPA-HQ-OPP-2008-0331

Pyrethroids and Pyrethrins Ecological Risk Mitigation Proposal and the FQPA Safety Factor Re-evaluation

Pyrethroids and Pyrethrins Revised Ecological Risk Mitigation and Response to Comments on the Ecological Risk Mitigation Proposal For 23 Chemicals

Allethrins EPA-HQ-OPP-2010-0022 Interim decision
Bifenthrin EPA-HQ-OPP-2010-0384

Interim Decision
Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative risk ecological assessment
Updated draft human health risk assessment

Cyfluthrin and beta-cyfluthrin EPA-HQ-OPP-2010-0684

Interim Decision
Proposed Interim Decision
Draft ecological assessment risk rationale
Draft preliminary comparative risk ecological assessment
Updated draft human health risk assessment

Gamma-cyhalothrin EPA-HQ-OPP-2010-0479

Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Draft human health risk assessment

Cypermethrin, alpha-cypermethrin, and zeta-cypermethrin EPA-HQ-OPP-2012-0167

Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Updated draft human health risk assessment

Cyphenothrin EPA-HQ-OPP-2009-0842

Interim Decision
Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Updated draft human health risk assessment

d-phenothrin EPA-HQ-OPP-2011-0539

Interim Decision
Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Updated draft human health assessment

Deltamethrin EPA-HQ-OPP-2009-0637

Interim Decision
Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Updated draft human health risk assessment

Esfenvalerate EPA-HQ-OPP-2009-0301

Interim Decision
Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Updated draft human health risk assessment

*Etofenprox EPA-HQ-OPP-2007-0804

Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Draft human health risk assessment

Fenpropathrin EPA-HQ-OPP-2010-0422

Interim Decision
Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Updated draft human health assessment

Flumethrin EPA-HQ-OPP-2016-0031

Interim Decision
Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Updated draft human health risk assessment

Imiprothrin EPA-HQ-OPP-2011-0692

Interim Decision
Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Updated draft human health assessment

Lambda-cyhalothrin EPA-HQ-OPP-2010-0480

Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Draft human health risk assessment

Momfluorothrin EPA-HQ-OPP-2015-0752

Interim Decision
Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Updated draft human health risk assessment

Permethrin EPA-HQ-OPP-2011-0039

Interim Decision
Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Updated draft human health risk assessment

Prallethrin EPA-HQ-OPP-2011-1009

Interim Decision
Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Updated draft human health assessment

Pyrethrins EPA-HQ-OPP-2011-0885

Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Draft human health risk assessment

Tau-fluvalinate EPA-HQ-OPP-2010-0915

Interim Decision
Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Updated draft human health assessment

Tefluthrin EPA-HQ-OPP-2012-0501

Interim Decision
Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Updated draft human health assessment

Tetramethrin EPA-HQ-OPP-2011-0907

Interim Decision
Proposed Interim Decision
Draft ecological risk assessment rationale
Draft preliminary comparative ecological risk assessment
Updated draft human health assessment

Tralomethrin EPA-HQ-OPP-2012-0425 Registration review decision completed

*Etofenprox is not a pyrethroid or pyrethrin but was assessed with the group due to its structural similarity.

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