title: Synergistic interaction between polycyclic aromatic hydrocarbons and environmental tobacco smoke on the risk of obesity in children and adolescents: The U.S. National Health and Nutrition Examination Survey 2003-2008.
abstract: BACKGROUND
  Polycyclic aromatic hydrocarbons (PAHs) may be obesogens. However, the role of PAHs independent of environmental tobacco smoke (ETS) is unclear, and the interaction between PAHs and ETS remains unknown.
  
  
  METHODS
  We performed cross-sectional analyses of urinary concentrations of PAH metabolites, body mass index (BMI), and waist circumference (WC) in 1985 people aged 6-18 years using data from the 2003-2008 U.S. National Health and Nutrition Examination Survey. ETS exposure level was measured as serum cotinine level.
  
  
  RESULTS
  PAH metabolites were positively associated with BMI and WC in both the ETS-unexposed and ETS-exposed groups. The adjusted odds ratios for general obesity defined by age- and sex-specific BMI≥95th percentile across the quartiles of total PAH metabolites were 1, 4.51, 2.57, and 8.09 (Ptrend=0.003) in the ETS-unexposed group and 1, 2.02, 1.83, and 3.86 (Ptrend<0.001) in the ETS-exposed group. However, the association of PAH metabolites with obesity became stronger as serum cotinine levels increased (Pinteraction<0.05). Among those with high ETS exposure, the adjusted odds ratios for general obesity across quartiles of total PAH metabolites were 1, 2.89, 5.26, and 16.29 (Ptrend<0.001). Compared to the low PAH-exposure group without exposure to ETS, the high ETS- and high PAH-exposure group had 33.85- and 17.64-fold greater risks of general and central obesity, respectively.
  
  
  CONCLUSIONS
  Environmental exposure to PAHs may be associated with childhood obesity irrespective of ETS. In particular, simultaneous exposure to PAHs and ETS may substantially increase the risk of obesity.
authors.affiliation: Department of Family Medicine, Daegu Medical Center, 157 Pyungli-ro, Seo-Gu, Daegu 703-713, Republic of Korea.
authors.forename: Hyun-Woo
authors.initials: HW
authors.lastname: Kim
authors.affiliation: Department of Preventative Medicine, School of Medicine, Kyungpook National University, 680 Gukchaebosang-ro, Jung-gu, Daegu 700-842, Republic of Korea.
authors.forename: Sin
authors.initials: S
authors.lastname: Kam
authors.affiliation: Department of Preventative Medicine, School of Medicine, Kyungpook National University, 680 Gukchaebosang-ro, Jung-gu, Daegu 700-842, Republic of Korea. Electronic address: lee_dh@knu.ac.kr.
authors.forename: Duk-Hee
authors.initials: DH
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D015992:Body Mass Index; D002648:Child; D003367:Cotinine / Q000097:blood; D003430:Cross-Sectional Studies; D006801:Humans; D015999:Multivariate Analysis; D009749:Nutrition Surveys; D009765:Obesity / Q000453:epidemiology*; D016017:Odds Ratio; D011084:Polycyclic Aromatic Hydrocarbons / Q000009:adverse effects* / Q000652:urine; D012307:Risk Factors; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*; D014481:United States / Q000453:epidemiology; D055105:Waist Circumference
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D014028:Tobacco Smoke Pollution; D003367:Cotinine
keywords: Environmental tobacco smoke; Interaction; NHANES; Obesity; Polycyclic aromatic hydrocarbons