Nevada researchers: Vaping leaves cancer-causing chemicals in lungs

Benjamin Spillman | Reno Gazette-Journal

Show Caption Hide Caption Desert_Research_Institute_scientist_explains_vaping_study Desert Research Institute scientist Andrey Khlystov explains study that showed vaping can leave cancer-causing chemicals in lungs of e-cigarette users.

People who use e-cigarettes as an alternative to traditional smoking are still retaining cancer-causing chemicals in their lungs, according to recent research.

That’s the conclusion of scientists at Desert Research Institute in Reno who studied what happens to harmful chemicals in the vapor people inhale while using the devices.

Vapor from e-cigarettes can include chemicals such as formaldehyde, a known carcinogen in humans.

“Until now, the only research on the respiratory uptakes of aldehydes during smoking has been done on conventional cigarette users,” said Vera Samburova, an associate research professor in DRI’s Division of Atmospheric Sciences.

More: Teens hooked by vaping: FDA weighing a ban on flavored e-cigarette liquids

Vaping uses an electronic device to heat liquid that can be flavored and contain nicotine and other compounds. The vaporized material can be inhaled via the device, such as a vape pen, e-cigarette, electronic hookah or Juul device. The inhaled and exhaled product creates a plume that looks similar to cigarette smoke.

Samburova and Andrey Khlystov, another DRI research professor, have been studying e-cigarettes for several years.

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

The researchers noted that while manufacturers tout vaping products as a safer alternative to cigarettes, liquids are marketed in flavors that are likely to appeal to young users who might not have been smokers in the first place.

Some of the flavors they tested in the lab included cotton candy, bubble gum and gummy bear.

"It is really highly oriented to young generation people," Samburova said. "Young people start using e-cigarettes, this is one way to get addicted to nicotine and start smoking conventional cigarettes."

"It is cleaner than conventional cigarettes, but it is still not completely clean," Khlystov said.

Their most recent findings are a follow-up to their earlier research that showed relatively harmless ingredients in e-cigarette liquids can break down and combine to form harmful compounds, such as formaldehyde, when heated and converted into vapor.

"That is where the formaldehyde comes from," Khlystov said. "It is not in the liquid, it is in the heating of the liquid."

To understand what people absorb when they inhale e-cigarettes, Samburova and Khlystov analyzed the breath of 12 people before and after vaping sessions.

They measured the concentration of aldehydes in the breath of the users, seven women and five men, before and after vaping.

They also used mechanical means to measure the concentration of the chemicals as the vapor leaves the e-cigarette when the users inhales.

The difference between the concentration of chemicals coming out of the e-cigarette and the breath of the users after vaping represents what’s left behind in the lungs, they said.

“We found that the average concentration of aldehydes in the breath after vaping sessions was about ten and a half times higher than before vaping,” Samburova said. “Beyond that, we saw that the concentration of chemicals like formaldehyde in the breath after vaping was hundreds of times lower than what is found in the direct e-cigarette vapors, which suggests significant amount is being retained in the user’s respiratory tract.”

The research showed that users retained as much as 99 percent of formaldehyde inhaled. They also retained other aldehydes, such as propionaldehyde, which studies on animals have linked to liver damage and high blood pressure.

The aldehydes, which Samburova said are water soluble which makes them susceptible to uptake by the lungs, are generally associated with the flavoring material in e-cigarette liquids, the researchers said.

They're in addition to other harmful compounds such as nicotine and particulate matter which e-cigarette users exhale into the air where other people can be exposed.

What it means is that vaping exposes non-users to hazards similar to the way cigarettes expose people to second hand smoke.

In fact, Samburova said vaping can create second and third hand exposure.

Second hand exposure comes when people breathe in exhaled vapor with nicotine and particulate matter. Third hand exposure occurs when the exhaled material settles on surfaces where it can contact people's hands and fingers.

Although the researchers took care to make sure the testing was similar to real-life vaping sessions, Samburova said there should be more research with a greater number of participants.

The journal “Toxics” published the study August 7.