APPLICATIONS OF TECHNOLOGY:
- Early detection, risk assessment and monitoring in-house exposure to thirdhand smoke (THS)
- Biomarker is unique to THS
Researchers at Berkeley Lab have shed light on the cellular mechanisms linking exposure to thirdhand smoke (THS) with oxidative stress, DNA damage and cancer risk. They have also identified a biomarker of THS exposure that is absent in cases of secondhand smoke (SHS) exposure, making the biomarker especially useful in establishing THS exposure and risk.
THS refers to tobacco smoke pollutants remaining on skin, clothing, furniture and other surfaces after tobacco has been smoked. It also includes the secondary pollutants formed when residual tobacco smoke pollutants react with other compounds in the environment. For example, sorbed nicotine reacts with nitrous acid, a common indoor air pollutant, to form mutagenic tobacco-specific nitrosamines (TSNAs). 1-(N-methyl-N-nitrosamino)-1-(3-pyridinyl)-4-butanal), or NNA, is the major TSNA product identified from THS that is absent in freshly emitted secondhand smoke.
The Berkeley Lab researchers found that NNA
- causes DNA strand breaks in cultured human HepG2 cells at non-cytotoxic concentrations,
- yields DNA adducts, including a covalent exocyclic dG adduct with structural information, which play a role in chemical carcinogenesis and may serve as a specific biomarker(s) of thirdhand smoke exposure, and
- causes novel DNA sugar damage.
The measurement of the observed DNA damage can be used to assess the affects of tobacco toxins. Since NNA is unique to THS, NNA-derived specific adducts represent an integrated biomarker of exposure to THS. As such, they could offer early detection of THS exposure and, ultimately, help prevent related health affects. In addition to detecting, assessing and monitoring exposure to THS, the researchers’ findings could be used to frame and enforce policies against smoking indoors.
DEVELOPMENT STAGE: Proven principle.
STATUS: Patent pending. Available for licensing or collaborative research.
FOR MORE INFORMATION:
Hang, B., Iavarone, A., Havel, C., Jacob III, P., Villalta, P., Matter, B., Sharan, D., Hang, M., Sleiman, M., Destaillats, H. Gundel, L., Chenna, A., “NNA, a Thirdhand Smoke Constituent, Induces DNA Damage in Vitro and in Human Cells,” poster presented at American Chemical Society Spring 2014 Annual Meeting.
REFERENCE NUMBER: 2014-060