Poster, SOT 65th Annual Meeting and ToxExpo, March 22–25, 2026, in San Diego, California.
Jessica R. Murray1, Marc Muraski1,2, Jonah Herwick3,4, Joseph Lewis3,4, Ari Ogunda3,4, Annie Jarabek3
1US EPA, OCSPP | OMCO | Risk Assessment Support Division, Research Triangle Park, NC; 2ORISE, Oak Ridge, TN;
3US EPA, ORD, Research Triangle Park, NC
4ORAU, Oak Ridge, TN.
Introduction
In the advancement of more accurate, animal-free inhalation risk assessments, the choice of exposure method is paramount. A recent study by the US EPA highlights why the Air–Liquid Interface (ALI) is a valuable approach for characterizing respiratory irritants.
While Direct Liquid Application (DLA) is easy to perform and widely used, it often introduces “vehicle effects”—unintended cellular stress caused by the liquid volume itself. The EPA’s findings show that ALI exposures remain remarkably stable, with vehicle controls performing identically to untreated incubator controls. This ensures that observed biological responses are driven by the irritant itself, not by the delivery method.
Using the VITROCELL® Cloud Alpha 12 system, researchers achieved uniform cell coverage and precise dose–response characterization across multiple human cell models.
As efforts continue to harmonize global testing standards, this technology offers the reliability and physiological relevance needed to bridge the gap between in vitro data and human health outcomes.
