title: Secondhand smoke exposure in Mexican discotheques.
abstract: This study describes the impact of exposure to secondhand smoke for subjects who spend time in a discotheque, by comparing within-subject baseline and postexposure urinary cotinine levels. A total of 100 nonsmoking volunteers from a central region of Mexico provided a urine sample before entering a discotheque and another sample an average of 6 hr after the end of exposure. Concentrations of cotinine and its metabolite, trans-3'-hydroxycotinine, were measured in the urine by liquid chromatography-mass spectrometry. In females the average preexposure level of urinary cotinine was 2.2 ng/ml, and the average postexposure level was significantly higher, at 15.7 ng/ml. In males the average preexposure level of cotinine was 3.7 ng/ml, compared with 49.1 ng/ml in the postexposure assessment. The highest postexposure values were found in men younger than 22 years old with a value of 469.5 ng/ml. Exposure to secondhand smoke is a serious health risk. Our findings are important given that many of our subjects were exposed to substantial amounts of secondhand smoke in discotheques, as evidenced by the high urinary cotinine and 3'-hydroxycotinine concentrations. These findings support the need to prohibit smoking in discotheques to protect nonsmokers' health.
authors.affiliation: Center for Research in Population Health, National Institute of Public Health, Cuernavaca, Morelos, Mexico. elazcano@correo.insp.mx
authors.forename: Eduardo
authors.initials: E
authors.lastname: Lazcano-Ponce
authors.forename: Neal
authors.initials: N
authors.lastname: Benowitz
authors.forename: Luisa Maria
authors.initials: LM
authors.lastname: Sanchez-Zamorano
authors.forename: Larissa
authors.initials: L
authors.lastname: Barbosa-Sanchez
authors.forename: Raydel
authors.initials: R
authors.lastname: Valdes-Salgado
authors.forename: Peyton
authors.initials: P
authors.lastname: Jacob
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Diaz
authors.forename: Mauricio
authors.initials: M
authors.lastname: Hernandez-Avila
mesh_terms: D000293:Adolescent; D000328:Adult; D016902:Air Pollution, Indoor / Q000032:analysis*; D003367:Cotinine / Q000031:analogs & derivatives* / Q000652:urine*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008297:Male; D008800:Mexico; D012147:Restaurants; D018570:Risk Assessment; D012307:Risk Factors; D014028:Tobacco Smoke Pollution / Q000032:analysis*
chemical_list: D014028:Tobacco Smoke Pollution; C001381:hydroxycotinine; D003367:Cotinine