A study led by researchers from Lawrence Berkeley National Laboratory has found for the first time that thirdhand smoke -- the noxious residue that clings to virtually all surfaces long after the secondhand smoke from a cigarette has cleared out -- causes significant genetic damage in human cells.
Furthermore, the study also found that chronic exposure is worse than acute exposure, with the chemical compounds in samples exposed to chronic thirdhand smoke existing in higher concentrations and causing more DNA damage than samples exposed to acute thirdhand smoke, suggesting that the residue becomes more harmful over time.
"This is the very first study to find that thirdhand smoke is mutagenic," said Lara Gundel, a Berkeley Lab scientist and co-author of the study. "Tobacco-specific nitrosamines, some of the chemical compounds in thirdhand smoke, are among the most potent carcinogens there are. They stay on surfaces, and when those surfaces are clothing or carpets, the danger to children is especially serious."
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