E-cigarettes have gained popularity as a “safer,” and increasingly more fashionable, alternative to traditional cigarettes. Yet recent research questions their actual safety, claiming that the e-liquid and vapors contain cancer-causing substances that can linger.

Experts warn that vaping causes e-cigarette users to inhale dangerous quantities of cancer-causing substances.

Many studies conducted over the past couple of years have found that, despite being advertised as a safer alternative to traditional cigarettes, electronic cigarettes (e-cigarettes) actually hide numerous threats to health.

One study that Medical News Today covered revealed that e-cigarette flavorings are toxic when it comes to heart health.

Another study even reported that “e-cigarettes might be just as bad as cigarettes.”

Also, one study paper published this year explains that e-cigarettes may produce dangerously high levels of formaledhyde.

Formaldehyde and other aldehydes are chemical compounds that harbor carcinogenic properties, meaning that prolonged exposure to these substances has the potential to cause cancer.

The question, however, is whether these substances are present in large enough quantities and linger in our bodies for long enough to actually cause harm.

A new pilot study from the University of Nevada in Reno suggests that the aldehydes released by e-cigarettes do get absorbed into the lungs in large quantities, which may pose significant health risks.

“Until now,” says lead study author Vera Samburova, “the only research on the respiratory uptake of aldehydes during smoking has been done on conventional cigarette users.”

“Little is known about this process for e-cigarette use,” she adds, “and understanding the unique risks vaping poses to users is critical in determining toxicological significance.”