title: Impact of environmental volatile organic compounds on otitis media in children: Correlation between exposure and urinary metabolites.
abstract: BACKGROUND
  Volatile organic compounds (VOCs) induce inflammatory responses. Tobacco smoke contains numerous VOCs and is a risk factor for otitis media effusion (OME); however, no previous studies have investigated the association between VOCs and OME.
  
  
  OBJECTIVE
  We used urinary metabolites and exposure to environmental risk factors to investigate the association between VOC and polycyclic aromatic hydrocarbon exposure and recurrent OME in children.
  
  
  METHODS
  Children with recurrent OME who visited the Otorhinolaryngology Department of Seoul National University Hospital between November 2014 and June 2015 were prospectively enrolled in the study. Recurrent OME was defined as more than two OME episodes over a 6-month period lasting longer than 2 months. The control group consisted of children without OME in the last year. Demographic information, including age, sex, and previous medical history was obtained, and endoscopic examinations of the tympanic membrane were performed. Urinary concentrations of 1-hydroxypyrene, 2-naphthol, hippuric acid, trans, trans-muconic acid (t,t-MA), mandelic acid, phenyl glyoxylic acid, and methyl hippuric acid were analyzed using high-performance liquid chromatography/tandem mass spectroscopy. Environmental factors assessed included house type, age, renovations, the presence of furniture <6 months old, proximity to a road, and exposure to passive smoking.
  
  
  RESULTS
  We enrolled 11 children with OME and 39 controls. Age and sex did not differ between groups. Exposure to passive smoking was significantly more common in the OME group than in the controls (P < 0.001). Urinary concentrations of t.t.-MA were significantly higher in the OME group (126.33 μg/g cr) than in controls (52.661 μg/g cr; P = 0.003). Other metabolites including 1-hydroxypyrene, 2-naphthol, hippuric acid, mandelic acid, phenyl glyoxylic acid, and methyl hippuric acid did not demonstrated significant relation with the OME.
  
  
  CONCLUSIONS
  Levels of t,t-MA, a biomarker of benzene exposure, were significantly higher in the OME group than in controls. Passive smoking was significantly more common in the OME group. Our findings suggest that high t,t-MA levels which were probably originated from passive smoking and other pollutants could be indicative OME in children.
authors.affiliation: Department of Otorhinolaryngology-Head & Neck Surgery, CHA Bundang Medical Center, CHA University, Seongnam, South Korea.
authors.forename: So Young
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Environment Health Science, Soonchunhyang University, South Korea.
authors.forename: Bu-Soon
authors.initials: BS
authors.lastname: Son
authors.affiliation: Department of Environment Health Science, Soonchunhyang University, South Korea.
authors.forename: Hee-Jin
authors.initials: HJ
authors.lastname: Park
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Seung Ha
authors.initials: SH
authors.lastname: Oh
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Jun Ho
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Myung-Hwan
authors.initials: MH
authors.lastname: Suh
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University College of Medicine, Seoul, South Korea. Electronic address: aseptic@snu.ac.kr.
authors.forename: Moo Kyun
authors.initials: MK
authors.lastname: Park
mesh_terms: D015415:Biomarkers / Q000652:urine; D002648:Child; D004781:Environmental Exposure / Q000009:adverse effects* / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D010033:Otitis Media / Q000150:complications*; D011084:Polycyclic Aromatic Hydrocarbons / Q000009:adverse effects*; D011446:Prospective Studies; D012008:Recurrence; D013011:Sorbic Acid / Q000031:analogs & derivatives / Q000032:analysis; D014028:Tobacco Smoke Pollution / Q000009:adverse effects; D055549:Volatile Organic Compounds / Q000009:adverse effects*
chemical_list: D015415:Biomarkers; D011084:Polycyclic Aromatic Hydrocarbons; D014028:Tobacco Smoke Pollution; D055549:Volatile Organic Compounds; C005939:muconic acid; D013011:Sorbic Acid
keywords: Children; Otitis media; Passive smoking; Trans; Trans-muconic acid; Volatile organic compounds