Toxicity Testing Workshop Recommends Replacing Animal Tests

The Physicians Committee

Toxicity Testing Workshop Recommends Replacing Animal Tests

Animal tests used to identify the effects inhaled chemicals have on the human respiratory system pose ethical and scientific issues. The Physicians Committee hosted a workshop on May 1-3 that outlined steps regulators and companies should take to replace animal tests with human-relevant methods.

The nearly 20 presenters at the Inhalation Toxicity: Pathways to Better Methods workshop included Kristie Sullivan, M.P.H., director of regulatory testing issues for the Physicians Committee, as well as representatives from the U.S. Environmental Protection Agency and Dow Chemical Company.

Extensive efforts have been made to develop in vitro and computer-based tests to detect toxicant-induced damage to the human respiratory system. However, no approach has been accepted by any regulatory agency.

Conference presenters recommended developing Adverse Outcome Pathways (AOPs) as a possible solution. AOPs can help avoid animal tests by organizing existing data on how toxins affect the respiratory into a pathway that predicts whether chemicals will cause further respiratory damage.

For example, an inhaled chemical that binds to lung cells may cause an allergic reaction in humans. Instead of using an animal to test for an allergic reaction, the scientific case can be made that chemicals that bind to an in vitro lung cell model will likely cause an allergic reaction.

Attendees called for creating and submitting an AOP to the Organisation for Economic Co-operation and Development (OECD), an international body that coordinates testing policies from various countries. Physicians Committee scientists have held the secretariat position of the International Council on Animal Protection in OECD Programmes since 2006. OECD acceptance of the proposed AOP would pave the way for regulatory acceptance of nonanimal inhalation testing methods.

Best practice recommendations for conducting in vitro tests using human cells and tissues were also developed during the conference. These recommendations will help ensure that data from respiratory studies using in vitro methods are used for regulatory purposes.

These outcomes of the conference promise to advance human health by increasing knowledge of respiratory system toxicity and developing methods to better predict it.

To learn more about the Physicians Committee’s efforts to modernize chemical testing, visit


Kristie Sullivan, M.P.H.
Kristie Sullivan, M.P.H.

To learn more about the Physicians Committee’s
efforts to modernize
chemical testing, visit

PCRM Online
June 2013