title: Child exposure to indoor and outdoor air pollutants in schools in Barcelona, Spain.
abstract: Proximity to road traffic involves higher health risks because of atmospheric pollutants. In addition to outdoor air, indoor air quality contributes to overall exposure. In the framework of the BREATHE study, indoor and outdoor air pollution was assessed in 39 schools in Barcelona. The study quantifies indoor and outdoor air quality during school hours of the BREATHE schools. High levels of fine particles (PM2.5), nitrogen dioxide (NO2), equivalent black carbon (EBC), ultrafine particle (UFP) number concentration and road traffic related trace metals were detected in school playgrounds and indoor environments. PM2.5 almost doubled (factor of 1.7) the usual urban background (UB) levels reported for Barcelona owing to high school-sourced PM2.5 contributions: [1] an indoor-generated source characterised mainly by organic carbon (OC) from organic textile fibres, cooking and other organic emissions, and by calcium and strontium (chalk dust) and; [2] mineral elements from sand-filled playgrounds, detected both indoors and outdoors. The levels of mineral elements are unusually high in PM2.5 because of the breakdown of mineral particles during playground activities. Moreover, anthropogenic PM components (such as OC and arsenic) are dry/wet deposited in this mineral matter. Therefore, PM2.5 cannot be considered a good tracer of traffic emissions in schools despite being influenced by them. On the other hand, outdoor NO2, EBC, UFP, and antimony appear to be good indicators of traffic emissions. The concentrations of NO2 are 1.2 times higher at schools than UB, suggesting the proximity of some schools to road traffic. Indoor levels of these traffic-sourced pollutants are very similar to those detected outdoors, indicating easy penetration of atmospheric pollutants. Spatial variation shows higher levels of EBC, NO2, UFP and, partially, PM2.5 in schools in the centre than in the outskirts of Barcelona, highlighting the influence of traffic emissions. Mean child exposure to pollutants in schools in Barcelona attains intermediate levels between UB and traffic stations.
authors.affiliation: Centre for Research in Environmental Epidemiology (CREAL), C/ Dr. Aiguader 88, 08003 Barcelona, Spain; Institute for Environmental Assessment and Water Research (IDÆA-CSIC), C/ Jordi Girona 18-26, 08034 Barcelona, Spain; Universitat Pompeu Fabra (UPF), C/ Dr. Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), C/ Monforte de Lemos 3-5, 28029 Madrid, Spain; Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona (UAB), Edifici C Campus de la UAB, 08193 Bellaterra Cerdanyola, Spain. Electronic address: irivas@creal.cat.
authors.forename: I
authors.initials: I
authors.lastname: Rivas
authors.affiliation: Institute for Environmental Assessment and Water Research (IDÆA-CSIC), C/ Jordi Girona 18-26, 08034 Barcelona, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Viana
authors.affiliation: Institute for Environmental Assessment and Water Research (IDÆA-CSIC), C/ Jordi Girona 18-26, 08034 Barcelona, Spain.
authors.forename: T
authors.initials: T
authors.lastname: Moreno
authors.affiliation: Institute for Environmental Assessment and Water Research (IDÆA-CSIC), C/ Jordi Girona 18-26, 08034 Barcelona, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Pandolfi
authors.affiliation: Institute for Environmental Assessment and Water Research (IDÆA-CSIC), C/ Jordi Girona 18-26, 08034 Barcelona, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Amato
authors.affiliation: Institute for Environmental Assessment and Water Research (IDÆA-CSIC), C/ Jordi Girona 18-26, 08034 Barcelona, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Reche
authors.affiliation: Centre for Research in Environmental Epidemiology (CREAL), C/ Dr. Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), C/ Dr. Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), C/ Monforte de Lemos 3-5, 28029 Madrid, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Bouso
authors.affiliation: Centre for Research in Environmental Epidemiology (CREAL), C/ Dr. Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), C/ Dr. Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), C/ Monforte de Lemos 3-5, 28029 Madrid, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Àlvarez-Pedrerol
authors.affiliation: Institute for Environmental Assessment and Water Research (IDÆA-CSIC), C/ Jordi Girona 18-26, 08034 Barcelona, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Alastuey
authors.affiliation: Centre for Research in Environmental Epidemiology (CREAL), C/ Dr. Aiguader 88, 08003 Barcelona, Spain; Hospital del Mar Research Institute (IMIM), C/ Dr. Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), C/ Dr. Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), C/ Monforte de Lemos 3-5, 28029 Madrid, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Sunyer
authors.affiliation: Institute for Environmental Assessment and Water Research (IDÆA-CSIC), C/ Jordi Girona 18-26, 08034 Barcelona, Spain.
authors.forename: X
authors.initials: X
authors.lastname: Querol
mesh_terms: D000393:Air Pollutants / Q000009:adverse effects* / Q000032:analysis; D016902:Air Pollution, Indoor / Q000009:adverse effects* / Q000032:analysis; D002119:Calcium Carbonate / Q000032:analysis; D002648:Child; D004781:Environmental Exposure; D004784:Environmental Monitoring / Q000706:statistics & numerical data*; D006801:Humans; D008168:Lung / Q000737:chemistry; D019216:Metals, Heavy / Q000009:adverse effects / Q000032:analysis; D009585:Nitrogen Dioxide / Q000009:adverse effects / Q000032:analysis; D052638:Particulate Matter / Q000009:adverse effects / Q000032:analysis; D012574:Schools; D013030:Spain
chemical_list: D000393:Air Pollutants; D019216:Metals, Heavy; D052638:Particulate Matter; D002119:Calcium Carbonate; D009585:Nitrogen Dioxide
keywords: Black carbon; Mineral matter; Organic carbon; PM(2.5); School indoor air; Ultrafine particles