UCSF

Significance: Thirdhand smoke (THS), which includes secondhand smoke contami- nants, can be re-emitted and re-suspended into the air and are embedded into carpets, floors, and clothing. The awareness of THS and the health impacts from exposure to its harmful residues is low in the general population of the United States, especially in immigrant communities where smoking remains prevalent. Our study implemented a THS family-based intervention to promote THS awareness among Chinese American immigrants. Methods: The THS intervention included an education and home cleaning component delivered by lay health workers to 30 Chinese American dyads (N=60). Dyads consisted of former smokers who quit within the last two years and their non-smoking family member living in the same household. Participants completed pre- and post-in- tervention survey interviews and a sub-sample (N=15; 8 former smokers and 7 family members) participated in a post-intervention focus group. Multivariable regression adjusted for dyadic data was conducted to compare pre- and post-intervention changes in the Beliefs About Thirdhand Smoke (BATHS) overall and subscale (Persistence and Health) scores. Transcriptions from focus group interviews, conducted in Cantonese, were transcribed and translated, coded by two independent researchers and themati- cally analyzed using Dedoose. Results: All participants were born outside the US and 59% immigrated at age 30 or older (range: 7 to 63 years old). A majority (82%) spoke English less than “well” and 87% were married. BATHS scores analyses suggested that former smokers increased their THS awareness from pre- to post-intervention: BATHS Overall (M=3.95 [SD=0.50], p=0.021); Persistence (M=3.95 [SD=0.48], p=0.031) and Health (M=3.94 [SD=0.58], p=0.038), and their post-intervention THS scores became similar to the BATH scores of non-smoking family members which did not change at post-intervention. Thematic analyses of focus group interviews revealed emerging themes highlighting impacts on former smokers in increasing THS knowledge and strengthening desires to create dialogue about tobacco use with friends; for example, a former smoker shared “I will share my [THS] knowledge with others. I think it will help [my friends] as well.” Conclusion: A family-based THS education intervention has promising impacts to advance tobacco control in Chinese American immigrant communities by providing new THS knowledge and encouraging former smokers to become agents of change. Future research on empowering former smokers to become effective agents of change to promote tobacco-free communities is warranted.