Secondhand e-cigarette aerosols expose kids to less nicotine than cigarettes, study finds, but can still be risky
To keep children completely nicotine-free, according to the researchers, people shouldn’t smoke or vape around kids at all.
The researchers said they did the study in part because of the perception that e-cigarettes were safer than traditional cigarettes and because people are using them more than regular cigarettes inside the home. The study published Thursday in the journal JAMA Network Open.
Vaping has been promoted to adults as a healthier alternative to traditional cigarettes and as a potential smoking cessation device, although experts say more research is needed.
One reason some doctors prefer that their patients use e-cigarettes is because they expose users to fewer toxic chemicals such as tobacco and the dozens of other carcinogens found in cigarettes, like N-nitrosamines and aldehydes, that can cause cancer and other serious health problems.
But what the new study shows, experts say, is that harm reduction for the user is not necessarily the same as harm removal for everyone around them — and this could be a significant issue for children, whose lungs are still developing.
The study looked at the lives of 1,777 children who were were part of the National Health and Nutrition Examination Survey, a racially diverse government study designed to continuously assess US child and adult health and nutrition. Tobacco use in the home was reported by parents or guardians. More than 270 of the kids were exposed to secondhand tobacco smoke at home, 45 were exposed to secondhand e-cigarette vapor only, and 1,476 had neither kind of user in their home.
Scientists included children between the ages of 3 and 11 because they were less likely than older kids to use nicotine products. The researchers determined children’s nicotine levels using blood samples taken between 2017 and 2020.
Although new vaping devices have been introduced to the US since that time and exposure levels may be different depending on device, the authors say their study can provide a good general understanding of nicotine exposure in the home. Exposure levels in the study are generally considered an undercount, they said.
The children in the study who had the most nicotine exposure by far were those who lived with people who smoked traditional tobacco products like cigarettes. With these products, kids have two chances to be exposed to nicotine: when the user exhales and in between puffs, when a lit cigarette or cigar sits in an ashtray.
E-cigarette users are believed to absorb 99% of the nicotine they inhale, but some of it gets released when they exhale after taking a drag on their device.
The children in the study with the lowest nicotine levels were those who had no exposure to secondhand aerosols of any kind at home. Kids who were exposed to e-cigarettes had some nicotine in their bodies, but they had absorbed 84% less than those who lived in homes with people who smoked only tobacco.
The takeaway from the research, the authors said, is that people need to stop any kind of vaping or smoking at home.
“Vaping inside the home around children should be avoided given that, even though nicotine itself has a limited risk profile, the increased absorption of nicotine from secondhand vapor suggests that the children were also exposed to other potentially harmful excipients from e-cigarettes,” the study says.
Earlier studies have found similar nicotine exposure among children in homes with cigarette and e-cigarette users. Dr. Terry Gordon, a professor in the Department of Medicine at NYU’s Langone Health who has done nicotine exposure research, said he was surprised that nicotine levels weren’t higher in households with e-cigarette users.
Some of his research has shown much higher nicotine levels in e-cigarette households than in the new study. Either way, he said, all of these studies should be a good reminder to vape users that they need to be careful around others, especially kids.
“Most of us toxicologists, we believe e-cigs are safer, but no one is ready to say they are safe because of the primary users of the devices as well as those who are exposed to secondary aerosols,” said Gordon, who was not involved in the latest study.
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Scientists are still trying to figure out exactly how harmful secondhand vape aerosols can be. It took years to understand this with cigarettes, said Dr. Panagis Galiatsatos, a pulmonologist and volunteer medical spokesperson for the American Lung Association.
Secondhand smoke from cigarettes has done real damage, said Galiatsatos, who was not involved in the new study. He said he has treated an entire generation of people who have developed cancer and other lung problems not because they smoked but because they grew up around adults who did.
In 2020, Galiatsatos published what is believed to be the first study to document significant injury in an adult with secondhand e-cigarette exposure. He says adults shouldn’t take a chance with a child’s health by vaping around them.
“A child who is growing, their lungs are so vulnerable,” he said. “We don’t completely know the effect it’s going to have on the next generation, just like we didn’t know what secondhand smoke did, but why even put your child in a position of becoming a future patient?”
The study highlights the need for adults to avoid vaping at home due to the increased absorption of nicotine by children, potentially exposing them to other harmful excipients from e-cigarettes. Earlier research has also shown similar nicotine exposure among children in homes with cigarette and e-cigarette users, underscoring the importance of considering the impact of secondhand aerosols on health.
