The practice of using ozone to remove the smell of tobacco smoke from indoor environments, including hotel rooms and the interiors of vehicles, is probably a bad idea, says a new study.
The research showed that ozone can react with the nicotine in secondhand tobacco smoke to form ultrafine particles that may become a bigger threat to asthma sufferers than nicotine itself.
Researchers with the Lawrence Berkeley National Laboratory (Berkeley Lab) found that these ultrafine particles also become major components of thirdhand smoke - the residue from tobacco smoke that persists long after a cigarette or cigar has been extinguished.
"Our study reveals that nicotine can react with ozone to form secondary organic aerosols that are less than 100 nanometers in diameter and become a source of thirdhand smoke," said Mohamad Sleiman, who led this research.
"Because of their size and high surface area to volume ratio, ultrafine particles have the capacity to carry and deposit potentially harmful organic chemicals deep into the lower respiratory tract where they promote oxidative stress," Sleiman said.
"Not only did we find that nicotine from secondhand smoke reacts with ozone to make ultrafine particles - a new and stunning development - but we also found that several oxidized products of ozone and nicotine have higher values on the asthma hazard index than nicotine itself," said co-author Lara Gundel.
"The tunable VUV light of Beamline 9.0.2's custom-built VUV aerosol mass spectrometer minimized the fragmentation of organic molecules and enabled us to chemically characterize the secondhand smoke and identify individual constituents of secondary organic aerosols," said Sleiman.
"The identification of multifunctional compounds, such as carbonyls and amines, present in the ultrafine particles, made it possible for us to estimate the Asthma Hazard Index for these compounds," he said.
The results of the survey were published in the journal Atmospheric Environment.