Electronic cigarettes may not produce smoke but new research suggests the vapour they release could still pose risks to people nearby.
A preliminary study has found that lingering clouds from e-cigarettes can transform indoors, forming tiny particles filled with metals and highly reactive chemicals that may damage lung tissue when inhaled.
The study, published in Environmental Science & Technology, examined what happens to e-cigarette vapour after it mixes with indoor air. Researchers found that as vape plumes age, they can develop a complex chemical mixture containing metal nanoparticles and reactive compounds known as peroxides. Together, these substances can generate free radicals – unstable molecules linked to tissue damage and inflammation.
Ying-Hsuan Lin, the study’s corresponding author and a researcher at the University of California, Riverside said: ‘Our study reveals that the chemical cocktail of metal nanoparticles and reactive peroxides in aged e-cigarette aerosols creates a unique profile of respiratory health risks, highlighting that secondhand vapor is something by-standers shouldn’t have to breathe.’
Unlike traditional cigarettes, e-cigarettes heat liquids to create an aerosol rather than burning tobacco. While this avoids smoke, previous research has shown that vape aerosols can still contain volatile organic compounds and metals. Indoors, these vapours can react with ozone – a common indoor air pollutant – forming new chemicals, including peroxides.
To better understand these reactions, the team conducted controlled laboratory experiments. They created a simplified vape liquid containing a single floral-scented flavoring compound and no nicotine. The liquid was used in two refillable vape devices and released into a chamber containing ozone. After aging for 90 minutes, the aerosols were collected and analysed.
The researchers detected metals such as iron, aluminum and zinc in particles from both devices, along with trace amounts of heavy metals including lead, arsenic and tin. The aerosols also contained similar levels of peroxide compounds. Notably, the smallest (ultrafine) particles had much higher concentrations of both metals and peroxides than larger particles.
To simulate what might happen inside the lungs, the team placed the aged aerosols into a water-based solution resembling lung fluid. The results showed that ultrafine particles generated far more free radicals – about 100 times more per unit weight than larger particles.
Because ultrafine particles can penetrate deep into the lungs and reach the delicate, fluid-lined air sacs known as alveoli, the researchers say these findings point to a potential risk for lung tissue damage and reduced respiratory function.
While the study does not measure real-world health outcomes, the authors say it highlights important gaps in understanding the effects of secondhand vaping and underscores the need for further research into indoor air quality and bystander exposure.
The full research can be read here.
Photo: E-Liquids UK
Leave a Reply