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 This website is no longer updated and links to external websites and some internal pages may not work.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 »


EPA Proposes Registration of New Rodenticide

For Release: October 7, 2019

EPA invites public comment on its proposal to register alphachloralose, a new rodenticide used to control mice inside homes and buildings. Alphachloralose is the first new rodenticide active ingredient in over 20 years and is less toxic to humans than many rodenticide alternatives.

This rodenticide provides a new tool that can control mice quickly. It acts by lowering body temperature in mice. Mice then experience hypothermia, enter a chemical-induced sleep and die within as little as a few hours.

Alphachloralose is an alternative to other rodenticides such as anticoagulants or neurotoxins, which are designed to kill mice by suppressing clotting factors and attacking the central nervous system. Alphachloralose is formulated as a paste. The paste is enclosed in a sachet, which is then placed in a tamper-resistant bait station. For these reasons, EPA expects exposure to alphachloralose to be negligible.

Alphachloralose is only lethal to small animals like house mice. Even if children or large animals were to ingest alphachloralose, they are unlikely to be affected by body temperature changes caused by this chemical.

To minimize potential risks to children or pets in the home, EPA proposes to include use directions on the pesticide label. Users are instructed to:

  • Keep the bait in a supplied, tamper-resistant bait station;
  • Store bait refills away from children and pets when not in use; and
  • Use waterproof gloves when handling the bait station as a general precaution for rodenticides.

Failure to follow the pesticide label is a violation of law.

The label does not permit outdoor use, so there is limited ecological exposure to non-target animals. Because alphachloralose acts within a few hours and is metabolized quickly, there is low risk to predators and scavengers that may consume the affected mice.

Alphachloralose is compatible with integrated pest management (IPM) practices. Alphachloralose is expected to fit in well with an overall IPM program that may include a combination of biological, cultural, physical and chemical tools to minimize health and environmental risks.

Public comments can be submitted to at Docket #: EPA-HQ-OPP-2019-0507 on or before Oct. 22, 2019.