title: Determinants of personal exposure to ozone in school children. Results from a panel study in Greece.
abstract: In the wider framework of the RESPOZE (ReSPiratory effects of OZone Exposure in Greek children) panel study, we investigated possible determinants of O3exposure of school children, measured with personal passive samplers, in Athens and Thessaloniki, Greece.
  
  
  
  Personal exposure to O3was measured for five weeks spread along the academic year 2013-14, in 186 school children in Athens and Thessaloniki, Greece. At the same time, at-school outdoor measurements were performed and ambient levels of 8-h daily maximum O3from fixed sites were collected. We also collected information on lifestyle and housing characteristics through an extended general questionnaire (GQ) and each participant completed daily time activity diaries (TADs) during the study period.
  
  
  
  Mean outdoor concentrations were higher during the warmer months, in the suburbs of the cities and in Athens. Personal exposure concentrations were significantly lower compared to outdoor. Daily levels of at-school outdoor and ambient levels of O3from fixed sites were significant determinants of personal exposure to O3. For a 10μg/m3increase in at-school outdoor O3concentrations and PM10measurements a 20.9% (95% CI: 13%, 28%) increase in personal exposure to O3was found. For a half an hour more spent in transportation an average increase of 7% (95% CI: 0.3%, 14.6%) in personal exposure to O3was observed. Among other possible determinants, time spent in transportation (TAD variable) and duration of open windows were the ones associated with personal O3exposure levels.
  
  
  
  Our results support the use of outdoor and ambient measurements from fixed sites in epidemiological studies as a proxy of personal exposure to O3, but this has to be calibrated taking into account personal measurements and time-activity patterns.
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, National and Kapodistrian University of Athens, Medical School, 75, Mikras Asias Street, 115 27 Athens, Greece.
authors.forename: Konstantina
authors.initials: K
authors.lastname: Dimakopoulou
authors.affiliation: School of Chemical Engineering, National Technical University of Athens, Athens, Greece.
authors.forename: Georgios
authors.initials: G
authors.lastname: Grivas
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, National and Kapodistrian University of Athens, Medical School, 75, Mikras Asias Street, 115 27 Athens, Greece.
authors.forename: Evangelia
authors.initials: E
authors.lastname: Samoli
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, National and Kapodistrian University of Athens, Medical School, 75, Mikras Asias Street, 115 27 Athens, Greece.
authors.forename: Sophia
authors.initials: S
authors.lastname: Rodopoulou
authors.affiliation: Pulmonary Department, G. Papanikolaou Hospital, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Dionisis
authors.initials: D
authors.lastname: Spyratos
authors.affiliation: Pulmonary Department, G. Papanikolaou Hospital, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Despoina
authors.initials: D
authors.lastname: Papakosta
authors.affiliation: 2nd Pulmonary Department, "ATTIKON" University Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece.
authors.forename: Anna
authors.initials: A
authors.lastname: Karakatsani
authors.affiliation: School of Chemical Engineering, National Technical University of Athens, Athens, Greece.
authors.forename: Archontoula
authors.initials: A
authors.lastname: Chaloulakou
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, National and Kapodistrian University of Athens, Medical School, 75, Mikras Asias Street, 115 27 Athens, Greece; Department of Primary Care & Public Health Sciences and MRC-PHE Centre for Environment and Health, King's College London, London, UK. Electronic address: kkatsouy@med.uoa.gr.
authors.forename: Klea
authors.initials: K
authors.lastname: Katsouyanni
mesh_terms: D002648:Child; D004781:Environmental Exposure / Q000032:analysis*; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods; D005260:Female; D006115:Greece; D006801:Humans; D008297:Male; D010126:Ozone
chemical_list: D010126:Ozone
keywords: Air pollution; Ozone; Panel study; Personal exposure; Time-activity diaries