Health scare of the week

Some of the most popular e-cigarette products used by millions of Americans every day may be contaminated with bacterial and fungal toxins that can cause lung disease. Researchers at Harvard looked at 75 e-cigarette cartridges and e-liquid products that were on sale in 2013 and found that 23 percent contained traces of endotoxin, a microbial agent found in bacteria, and 81 percent had traces of glucan, a toxic substance common in fungi. Both toxins have been linked to health issues such as asthma, inflammation, and reduced lung function. Overall, cartridges contained 3.2 times higher concentrations of glucan than the liquid products. The source of the contamination isn’t clear, but the researchers speculate that the cotton wicks in single-use cartridges may be responsible, because endotoxin and glucan are known contaminants of cotton fibers. “[These findings] add to the growing concerns that we have about the safety of e-cigarettes,” lead author David Christiani tells NBCNews.com. “People should not assume that e-cigarettes are safe.”

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