Children exposed to vaping indoors absorb less than one-seventh the amount of nicotine as children who are exposed to indoor smoking.
RT’s Three Key Takeaways:
- Reduced Nicotine Absorption: The study found that children exposed to indoor vaping absorb less than one-seventh the amount of nicotine compared to children exposed to indoor smoking, but still more than those not exposed to either.
- Lower Risk of Harmful Substances: Researchers highlighted that while nicotine levels from secondhand vaping are significantly lower than from smoking, the exposure to other harmful substances present in vapor is likely much lower still, suggesting that concerns about secondhand vaping may be overstated.
- Implications for Indoor Vaping Policies: Researchers say the findings suggest that the health impact of secondhand vaping is much less than smoking, providing evidence for policy considerations on whether to allow vaping indoors, though caution is advised to avoid normalizing vaping behavior around children.
Children exposed to vaping indoors absorb less than one-seventh the amount of nicotine as children who are exposed to indoor smoking, but more than those exposed to neither, according to a new study led by Univeristy College London (UCL) researchers.
The study, published in JAMA Network Open and funded by Cancer Research UK, looked at blood tests and survey data for 1,777 children aged 3 to 11 in the United States.
The researchers said that secondhand exposure to harmful substances in e-cigarettes would likely be much lower still, as e-cigarettes deliver similar levels of nicotine to tobacco but contain only a fraction of the toxicants and carcinogens.
Real-World Data on Nicotine Absorption
The researchers looked at nicotine absorption in children, but they said the findings were likely to be similar for adults.
“Our study shows, using data from the real world rather than an artificial lab setting, that nicotine absorption is much lower from secondhand vapor than from secondhand smoking,” says lead author Harry Tattan-Birch, PhD, of the UCL Institute of Epidemiology and Health Care, in a release. “Nicotine itself is of limited risk, but it shows what the highest possible exposure might be from secondhand vaping. Exposure to harmful non-nicotine substances present in vapor will likely be substantially lower still.”
The study used data from a nationally representative sample of children in the US, collected between 2017 and 2020 as part of the annual US National Health and Nutrition Examination Survey.
Study Methodology and Findings
Blood tests that detected the concentration of cotinine were used to assess how much nicotine the children had absorbed. Cotinine is a chemical the body produces after exposure to nicotine. Survey responses indicated if the children had been exposed to smoking or vaping indoors in the past week.
The researchers focused on data from children as, unlike adults, children were unlikely to have vaped or smoked themselves, meaning higher nicotine absorption was a result of secondhand vapor or smoke only. However, two children were excluded from the analysis for having a cotinine concentration that suggested they had vaped or smoked directly. Children exposed to both indoor smoking and vaping were also excluded from the analysis.
The team found that children exposed to indoor vaping absorbed 84% less nicotine than children exposed to indoor smoking, while children exposed to neither absorbed 97% less.
Implications for Secondhand Vaping Risks
The lower levels of nicotine among those exposed to secondhand vaping were consistent with previous laboratory studies finding that people retained 99% of the nicotine they produced during vaping. With tobacco cigarettes, smoke is generated both by smokers breathing out as well as by the lighted end of the cigarette. E-cigarettes, however, do not generate aerosol aside from when vapers exhale.
“This paper suggests that concerns about secondhand vaping may be somewhat overstated, with secondhand exposure to toxic substances likely to be very low. The findings confirm the risks of smoking indoors around children, which should be avoided at all costs,” says senior author professor Lion Shahab, PhD, of the UCL Institute of Epidemiology & Health Care, in a release. “However, as secondhand vaping still exposes children to more harmful substances than no vaping or smoking exposure at all, it is best to avoid indoor vaping around children, too.”
Policy Considerations and Future Research
The researchers said their findings had implications for whether vaping should be allowed indoors, providing further evidence that the impact of vaping on bystanders’ health will be much less than smoking.
However, the researchers said there were other factors to consider when assessing whether indoor spaces should be made vape-free. In particular, if vaping commonly occurs indoors, this may normalize the behavior, encouraging people to start vaping and making it harder for them to stop.
Previous research from the same team showed that adults in England were much more likely to vape than smoke indoors, with nine in 10 vapers found to vape inside, while only half of smokers smoked inside.
Photo 103669426 © Nullplus | Dreamstime.com
