A recent study found bacterial and fungal toxins in various popular e-cigarette products sold in the U.S.
The study, published online in was carried out by researchers from the Harvard T.H. Chan School of Public Health in Boston, Massachusetts. The team studied 37 single-use e-cigarette cartridges and 38 e-liquids from the 10 top-selling US brands.
The products were split into four different flavor categories -- tobacco, menthol, fruit and other -- before being screened for the presence of endotoxin and glucan, microbial toxins which can cause damage to the lungs.
The scientists found that 23 percent of the products contained detectable concentrations of endotoxin. Traces of glucan were detected in 81 percent of the e-cigarette products tested.
"Finding these toxins in e-cigarette products adds to the growing concerns about the potential for adverse respiratory effects in users," warned David Christiani, Elkan Blout Professor of Environmental Genetics and senior author of the study.
The research also revealed that concentrations of endotoxin were higher in fruit-flavored products, suggesting that the raw materials used to produce the flavors might be a source of microbial contamination.
According to the study authors, the cotton wicks used in e-cigarette cartridges might be a potential source of contamination, since both endotoxin and glucan are known contaminants of cotton fibers. "These new findings should be considered when developing regulatory policies for e-cigarettes," concluded Mi-Sun Lee, lead author of the paper.
