Who is most likely to be exposed to thirdhand smoke?

Watch a video that answers this question here.

Thirdhand smoke is the chemical residue from tobacco smoke. It is also called “tobacco smoke residue” or “stale tobacco smoke.” The chemicals in thirdhand smoke are toxic to humans, especially children. It can linger for years in dust and on household surfaces. It can also become embedded in carpets, furniture, clothes, and building materials. It is difficult and expensive to remove.

Infants and young children are the most likely to be exposed to thirdhand smoke for these three reasons:

1. Time Indoors:

Infants and young children spend more time on average indoors than adults. Human activity surveys have shown that infants spend 90% of their time indoors at home. If these environments are polluted with thirdhand smoke, infants are at a higher risk of exposure.

2. Behavior:

Infants and young children explore their environment with their hands and bodies. Before they can walk, they move around by crawling along the floor–picking up dust and particles along the way. Their small size lets them fit into tight spaces where dust and particles might collect. Through crawling and exploring their environment, their hands, mouths, hair, clothes, and toys can collect thirdhand smoke. It can enter their bodies not just through their skin, but also through their lungs and mouths.

Children and infants put many objects into their mouths: their own hands, toys, blankets, their parents’ fingers, or a car seat strap. Just about anything they discover goes into their mouths, including everyday objects parents may use to distract a child, such as a cell phone, car keys, or the TV remote. The surfaces of objects can be contaminated with toxic thirdhand smoke in the air or dust, and when children put them in their mouths, thirdhand smoke chemicals enter their bodies.

3. Growth and Development

The respiratory systems of infants and young children are developing, and they breathe more times each minute than an adult does. This increased respiratory rate means that in relation to their size, they can breathe in more thirdhand smoke than adults can. Additionally, their organ systems are immature and growing—this includes their skin. The skin of an infant or child is thinner than the skin of adults, making them more susceptible to exposure from thirdhand smoke by dermal absorption. Their immune systems are also developing, making them more vulnerable to the effects of tobacco pollutants than adults.

Do you have more questions about the toxic legacy of tobacco smoke, how it affects human health, and what we can do about it? Learn more here.

Updated: February 2023

Sources:

Breunis, L. J., Versteylen, M., Radó, M. K., Dereci, N., Boderie, N. W., de Kroon, M. L. A., Been, J. V. (2022). Pediatric patients’ views regarding smoke-free hospital grounds compared to those of adults: A survey study. Tobacco Prevention & Cessation, 8 Feb, https://doi.org/10.18332/tpc/145311.

He, L., Zhou, Y.-X., Zhang, Y., Hang, B., Chang, H., Schick, S.F., Celniker, S.E., Xia, Y., Snijders, A.M. and Mao, J.-H. (2021), Thirdhand cigarette smoke leads to age-dependent and persistent alterations in the cecal microbiome of mice. MicrobiologyOpen, 10: e1198. https://doi.org/10.1002/mbo3.1198.

Kelley ST, Liu W, Quintana PJE, Hoh E, Dodder NG, Mahabee-Gittens EM, Padilla S, Ogden S, Frenzel S, Sisk-Hackworth L, Matt GE. Altered microbiomes in thirdhand smoke-exposed children and their home environments. Pediatr Res. 2021 Dec;90(6):1153-1160. https://doi.org/10.1038/s41390-021-01400-1.

Mahabee-Gittens EM, Merianos AL, Jandarov RA, Quintana PJE, Hoh E, Matt GE, Differential associations of hand nicotine and urinary cotinine with children’s exposure to tobacco smoke and clinical outcomes, Environmental Research. 2021. 202:111722. https://doi.org/10.1016/j.envres.2021.111722.

Mahabee-Gittens EM, Merianos AL, Matt GE. Preliminary evidence that high levels of nicotine on children’s hands may contribute to overall tobacco smoke exposure. Tob Control. 2018;27(2):217-219. doi: 10.1136/tobaccocontrol-2016-053602.

Mahabee-Gittens EM, Merianos AL, Quintana PJE, Hoh E, Matt GE. Nicotine on children’s hands: Limited protection of smoking bans and initial clinical findings. Tob Use Insights. 2019;12:1-6. doi:10.1177/1179173X18823493.

Mahabee-Gittens EM, Merianos AL, Stone L, Wullenweber CA, Quintana PJE, Hoh E, Dodder NG, Lopez-Galvez N, Matt GE, Hand nicotine as an independent marker of thirdhand smoke pollution in children’s environments, Science of The Total Environment, Volume 849, 2022, 157914, ISSN 0048-9697, https://doi.org/10.1016/j.scitotenv.2022.157914.

Matt GE, Quintana PJE, Hovell MF, Bernert JT, Song S, Novianti N, Juarez T, Floro J, Gehrman C, Garcia M, Larson S. Households contaminated by environmental tobacco smoke: sources of infant exposures. Tobacco Control. 2004;13:29–37. http://dx.doi.org/10.1136/tc.2003.003889.

Merianos AL, Jandarov RA, Gordon JS, Lyons MS, Mahabee-Gittens EM (2021) Healthcare resources attributable to child tobacco smoke exposure. PLOS ONE 16(2): e0247179. https://doi.org/10.1371/journal.pone.0247179.

Merianos AL, Mahabee-Gittens EM, Choi K, Tobacco smoke exposure and inadequate sleep among U.S. school-aged children, Sleep Medicine, Volume 86, 2021, Pages 99-105, ISSN 1389-9457, https://doi.org/10.1016/j.sleep.2021.08.012.

Northrup TF, Khan AM, Jacob P, Benowitz NL, Hoh E, Hovell MF, Matt GE, Stotts AL. Thirdhand smoke contamination in hospital settings: Assessing exposure risk for vulnerable pediatric patients. Tob Control. 2016;25: 619-623. Epub: 2015 Dec 3. http://dx.doi.org/10.1136/tobaccocontrol-2015-052506.

Parks, J., McLean, K.E., McCandless, L. et al. Assessing secondhand and thirdhand tobacco smoke exposure in Canadian infants using questionnaires, biomarkers, and machine learning. J Expo Sci Environ Epidemiol 32, 112–123 (2022). https://doi.org/10.1038/s41370-021-00350-4.