Vaping Additives Harm Lung Membrane: Study

The e-cigarette additive tocopherol—an organic compound better known as vitamin E—and tocopherol acetate can damage the lungs, according to two Concordia University researchers writing in Langmuir.

When heated and inhaled, the compound embeds in the pulmonary surfactant, a nanoscopically thin lipid protein membrane coating the surface of the alveoli that regulates the oxygen-carbon dioxide gas exchange and stabilizes the lungs’ surface tension during breathing.

The researchers used one-molecule-thick model membranes called Langmuir films to simulate the expansion and compression of the pulmonary surfactant. They then added vitamin E, which is structurally similar to the lipids found in the membrane.

They used different observational techniques including microscopy, x-ray diffraction and x-ray reflectivity. The researchers observed how the presence of the additive changed the surfactant’s properties and monitored changes as they added more to simulate how a real surfactant would accumulate and retain the compound in the lungs.

“We can see that the presence of vitamin E changes the functional properties of the surfactant,” said Christine DeWolf, a professor in the Department of Chemistry and Biochemistry and co-founder of the Centre for NanoScience Research at Concordia University, in a statement.

“Oxygen is exchanged for carbon dioxide across the pulmonary surfactant, so if the surfactant properties are altered, so can be the ability for gas to be exchanged. And if the surface tension is changed, that affects the work of breathing. So combined, these changes make breathing more difficult. We think this is the molecular basis contributing to the shortness of breath and reduced oxygen levels seen in people suffering from EVALI [electronic cigarette or vaping product use–associated lung injury]”

This paper is the first of a larger project that looks at the components of the vaping solutions that deliver the nicotine or cannabinoids to users.

“Many of the components in these solutions are approved by the United States Food and Drug Administration for other uses,” DeWolf says. “But the high heating rates needed to vaporize these components can cause further chemical reactions to occur. The components that are actually being inhaled may not be the ones in the original e-liquid.”