Sociodemographic disparities in thirdhand smoke exposure among children in the United States: a narrative review

Abstract

Thirdhand smoke (THS) is the toxic residue left behind by tobacco smoke that persists indoors on carpets, furniture, toys, and other items. Children are especially vulnerable to THS exposure due to their hand-to-mouth behaviors, activity near the floor, and developing organs. We provide a scoping narrative review of potential sociodemographic disparities in exposure to THS among children in the United States. Articles were obtained by conducting a search in the PubMed, SCOPUS, and CINAHL databases. Other relevant papers were also reviewed and integrated using narrative synthesis. Studies relevant to THS exposure among 0 to 17-year-olds and conducted in the United States were included. We identified lower socioeconomic status (SES), race, younger age (2-4 years), and living in multiunit housing (MUH) as potential contributors to higher THS exposure risk in children. Lower income was associated with greater THS exposure. THS exposure was higher in Black children, although the number of studies involving them was limited. Examining disparities in exposure and susceptibility to THS can inform future policies to reduce children’s environmental exposure to toxic tobacco chemicals in THS. Housing type is likely a primary contributor to exposure disparities, as low-income children are more likely to live in multiunit, rented housing, where tobacco smoke can travel across housing units and where THS residue from former tenants can persist. Policies limiting persistent THS residue indoors through comprehensive smoking bans and expanded outreach on approaches to reduce THS exposures among children are needed.