The analysis was published in the American Journal of Respiratory and Critical Care Medicine last December, and co-authored by David Christiani, Elkan Blout Professor of Environmental Genetics, and Mi-Sun Lee, research associate in the Department of Environmental Health.
In 2018, Christiani and Lee, along with Harvard Chan School’s Joseph Allen, assistant professor of exposure assessment science, had conducted a study that found bacterial and fungal toxins in many popular e-cigarette products sold in the U.S. However the earlier study had excluded Juul, and given its popularity the researchers decided to analyze some of its products for the current study.
A total of 54 Juul pods were tested for two types of microbial toxins: Endotoxin, a microbial agent and Glucan, a component of fungal cell walls. The researchers found that Endotoxin levels were below the limit of detection. However, 46% of the samples contained detectable levels of glucan.
The researchers said that chronic exposure to glucan can cause inflammation in the airway and lead to long-term lung damage. However, Christiani emphasized that this finding is not related in any way to the current outbreak of “vape-related” illness across the United States. The CDC has confirmed that the latter is being caused by the consumption of illicit THC products.