title: Thirdhand smoke: Chemical dynamics, cytotoxicity, and genotoxicity in outdoor and indoor environments.
abstract: We tested the toxicity of thirdhand smoke (THS) using two controlled laboratory exposure scenarios and low levels of THS. One exposure modeled THS in a car parked outdoors, while the second modeled THS in a room without sunlight. The fabrics were exposed to cigarette smoke and then extracted in culture medium. Concentrations of nicotine, nicotine related alkaloids, and tobacco specific nitrosamines (TSNAs) were determined in fresh and aged extracts. The concentration of TSNAs increased with aging in the indoor experiment. THS extracts were used for cytotoxicity testing using mouse neural stem cells (mNSC), human dermal fibroblasts (hDF) and human palatal mesenchyme cells (hPM). Extracts from the car experiment inhibited mNSC proliferation in a live cell imaging assay and induced single strand DNA breaks in mNSC and hDF. In the indoor experiment, THS extracts made with medium containing serum proteins were significantly more toxic than extracts made with basal medium, and mNSC and hPM were more sensitive than hDF. These data indicate that: (1) aging of THS chemical differs on different fabrics and differs with and without sunlight; (2) very few cigarettes are sufficient to produce a toxic THS residue; and (3) protein enhances the efficiency of extraction of cytotoxic chemicals.
authors.affiliation: Department of Cell Biology and Neuroscience, University of California, Riverside, CA, USA; Environmental Toxicology Graduate Program, USA. Electronic address: bahl.vasu@gmail.com.
authors.forename: Vasundhra
authors.initials: V
authors.lastname: Bahl
authors.affiliation: Department of Cell Biology and Neuroscience, University of California, Riverside, CA, USA. Electronic address: shjun112@gmail.com.
authors.forename: Hyung Jun
authors.initials: HJ
authors.lastname: Shim
authors.affiliation: Department of Clinical Pharmacology, University of California, San Francisco, CA, USA. Electronic address: pjacob@medsfgh.ucsf.edu.
authors.forename: Peyton
authors.initials: P
authors.lastname: Jacob
authors.affiliation: Department of Cell Biology and Neuroscience, University of California, Riverside, CA, USA. Electronic address: kdias001@ucr.edu.
authors.forename: Kristen
authors.initials: K
authors.lastname: Dias
authors.affiliation: Department of Medicine, Division of Occupational and Environmental Medicine, University of California, San Francisco, CA, USA. Electronic address: suzaynn.schick@ucsf.edu.
authors.forename: Suzaynn F
authors.initials: SF
authors.lastname: Schick
authors.affiliation: Department of Cell Biology and Neuroscience, University of California, Riverside, CA, USA. Electronic address: talbot@ucr.edu.
authors.forename: Prue
authors.initials: P
authors.lastname: Talbot
mesh_terms: D000393:Air Pollutants / Q000528:radiation effects / Q000633:toxicity*; D016902:Air Pollution, Indoor / Q000009:adverse effects*; D000470:Alkaloids / Q000032:analysis; D000818:Animals; D001336:Automobiles; D002478:Cells, Cultured; D004249:DNA Damage; D005260:Female; D005347:Fibroblasts / Q000187:drug effects; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000187:drug effects; D051379:Mice; D008875:Middle Aged; D058953:Neural Stem Cells / Q000187:drug effects; D009602:Nitrosamines / Q000032:analysis; D013472:Sunlight; D013784:Textiles / Q000032:analysis; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*
chemical_list: D000393:Air Pollutants; D000470:Alkaloids; D009602:Nitrosamines; D014028:Tobacco Smoke Pollution
keywords: Cigarette smoke; Nicotine; Stem cells; Thirdhand smoke; Tobacco; Tobacco specific nitrosamines; Toxicity