Inhaling common disinfectant chemicals known as quaternary ammonium compounds (QACs) can be far more harmful than swallowing them, according to a mouse study by researchers at the University of California, Davis. This study found significant lung damage at blood QAC exposure levels similar to those measured in humans.
The findings raise questions about whether airborne infections from disinfectant sprays and cleaning products can contribute to respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD). The study was published in the journal Environment Science and Technology.
The study’s surprising results were that inhaling these compounds caused 100 times more lung damage and 100 times more mortality than ingesting them. ”
Gino Cortopassi, first author, biochemist and pharmacologist, University of California Davis Weill School of Veterinary Medicine
Widespread use and growing concern
Quaternary ammonium compounds have been widely used as disinfectants since the 1940s under the trade names Lysol and Roccal. While these are less volatile, meaning they don’t produce smoke on their own, they are often used in disinfectant sprays that can get into your lungs. This compound is also found in some herbicides, eye disinfectants, nasal sprays, mouthwashes, dryer sheets, and fabric softeners.
It was once thought that these compounds did not pass into the bloodstream, but in 2021 Cortopassi et al. found that 80% of study participants had detectable concentrations of QACs in their blood. They also observed that participants with the highest levels of total QAC in their blood had the lowest energy levels in mitochondria, the part of the cell that produces energy. Because QACs do not penetrate well into the skin or intestines, the researchers thought that inhaling QACs might explain why the chemicals appear in human blood.
Link to human exposure
A new study found that when mice inhaled lung-harming levels of QAC, the amount of these chemicals that ended up in their blood was comparable to the QAC levels found in human blood. This suggests that inhaling these chemicals, such as from spray cleaners, may be one of the ways they enter the human body.
“We have to question whether we really want to have all these QAC-based disinfectant sprays in the environment, given the proven lung toxicity in mice,” Cortopassi said.
Other authors include Lauren Adcock, Claire B. Montgomery, Sepal Balkhardari, Sandipan Dutta, and Laura Van Winkle of the University of California, Davis. Kyungmi Kim of UC Davis Health; Ryan Seguin and Libin Xu of the University of Washington;
This research was funded by the National Institute of Environmental Health Sciences of the National Institutes of Health.
sauce:
University of California, Davis
Reference magazines:
Adcock, L. others. (2026). Differences and sex-specific toxicity of inhaled quaternary ammonium compounds. environmental science and technology. DOI: 10.1021/acs.est.5c13204. https://pubs.acs.org/doi/10.1021/acs.est.5c13204
