Can Your Lungs Smell Odors?

By Jane Farrell

When you smell something, you’re probably using your lungs as well as your nose, researchers say.

Investigators from Washington University in St. Louis and the University of Iowa have shown that the lungs have odor receptors. So when you smell cigarette smoke, the experts found, your lungs register the odor, triggering a process that ultimately makes your airways constrict.

This newly discovered class of cells, which express olfactory receptors in human airways, is called pulmonary neuroendocrine cells, or PNECs. They were found by a team led by Yehuda Ben-Shahar, PhD, assistant professor of biology and medicine at Washington University

“We forget,” said Ben-Shahar, “that our body plan is a tube within a tube, so our lungs and our gut are open to the external environment. Although they’re inside us, they’re actually part of our external layer. So they constantly suffer environmental insults,” he said, “and it makes sense that we evolved mechanisms to protect ourselves.”

Researchers theorized that the cells might cause the chemical hypersensitivity that characterizes respiratory diseases, such as chronic obstructive pulmonary disease (COPD) and asthma. By blocking the cells, they said, it might be possible to prevent some attacks, allowing people to cut down on the use of steroids or bronchodilators.

The findings were published in the Journal of Respiratory Cell and Molecular Biology.