Elsevier

Atmospheric Environment

Volume 55, August 2012, Pages 80-89
Atmospheric Environment

Indoor and outdoor characterisation of organic and inorganic compounds in city centre and suburban elementary schools of Aveiro, Portugal

https://doi.org/10.1016/j.atmosenv.2012.03.059Get rights and content

Abstract

Pollutants inside school buildings may affect children's health and influence learning performance and attendance. This study investigated pollutant concentrations inside and outside school buildings at different locations (city centre and suburban) in Aveiro, Portugal, between April and June 2010. The aim was to evaluate simultaneously comfort parameters (temperature, relative humidity, CO2 and CO) and indoor and outdoor concentrations of VOCs, NO2, PM10 and bioaerosols. PM10 samples were analysed and characterised, for the first time, for the water soluble inorganic ions (WSII), organic carbon (OC), elemental carbon (EC), carbonates, and detailed organic speciation. The CO2 and bioaerosol levels were higher than the acceptable maximum values to the occupants' comfort. Concentrations of the traffic tracer NO2 were higher outdoors. The daily indoor PM10 levels were always higher than those outdoors, except on weekends, suggesting that the physical activity of pupils and class works highly contributed to the emission and resuspension of particles. Almost all identified VOCs showed I/O ratios higher than one, which denotes an important contribution from indoor sources at both schools. The suburban school was more exposed to industrial emissions than the institution located in the city centre. Especially at the city centre, infiltration of outdoor particulates leads to contamination of school indoor environment with vehicle emissions and biomass burning smoke likely coming from biofuel use in nearby restaurants and bakeries.

Highlights

► For most pollutants, concentrations indoors are higher than outdoors. ► About 74% of PM10 is generated indoors. ► Pupils' physical activity and classroom works contribute to high indoor PM10 levels.

Introduction

It has been shown that indoor air quality (IAQ) is usually worse than the outdoor air (Godoi et al., 2009; Jo and Seo, 2005; Kotzias et al., 2009; Lee and Chang, 2000; Pegas et al., 2010, Pegas et al., 2011a, Pegas et al., 2011b; Yang et al., 2009). People are exposed to a multitude of chemical and biological stressors, some of which cause health problems (allergy, asthma, sensory irritation, hypersensitivity pneumonitis, lung cancer, etc.) (Bernstein et al., 2008; Jie et al., 2011; Rios et al., 2009; Samet and Spengler, 2003). On the other hand, some indoor air pollutants, such as dust and water vapour, accumulate on equipments, increasing the chance of an electrical breakdown (Lohbeck, 2008). Results of many studies demonstrate a significant and causal correlation between improving the indoor environment and gains in productivity and health (Fisk, 2000; Fisk and Rosenfeld, 1997; Kats et al., 2003; Kumar and Fisk, 2002; Mendell and Heath, 2005; Mudarri and Fisk, 2007; Seppanen et al., 2007).

Children, as result of the immaturity of immunity system and of growing processes, are more fragile and susceptible to indoor pollution effects (Mendell and Heath, 2005). Children in scholar age spend an important fraction of their time indoors in schools. In Portugal school buildings are frequently old and degraded, potentiating negative health effects in their young occupants.

As result of predictable impact of school IAQ in children health several studies have been performed worldwide in this topic (Daisey et al., 2003; Mendell and Heath, 2005). The pollutants most commonly measured in elementary school studies are gaseous compounds, which comprise total or speciated volatile organic compounds, formaldehyde and nitrogen dioxide, as well as biological agents including airborne fungi and bacteria (e.g. Blondeau et al., 2004; Godoi et al., 2009; Jo and Seo, 2005; Lee and Chang, 2000; Meklin et al., 2002; Pegas et al., 2011a, Pegas et al., 2011b; Yang et al., 2009). Comparatively to these traditional pollutants, indoor concentrations of particles at schools have been sparsely investigated. In spite of the various studies performed worldwide to assess the pupils' exposure to indoor particles, only a few aimed at characterising their chemical composition, and this was mainly focused on the elemental content (e.g. Almeida et al., 2011; Molnár et al., 2007; Oeder et al., 2012; Stranger et al., 2008). Nevertheless, practically nothing is known about the organic speciation and the respective sources of particles in the indoor air of schools. Due to their carcinogenic potential, only polycyclic aromatic hydrocarbons (PAHs) in the indoor air of residences, offices or commercial spaces have been characterised in a number of studies (Chalbot et al., 2006; Johannesson et al., 2009; Jung et al., 2010; Naumova et al., 2002, Naumova et al., 2003; Ohura et al., 2004).

In the present study, in addition to traditional measurements, a detailed chemical characterisation of particles occurring in both indoor and outdoor environments of elementary schools was performed. As far as we know, the abundances of several classes of organic compounds in airborne particles in schools were obtained for the first time. Such information is important as it appends to the emergent global-wide dataset of IAQ in educational buildings.

Section snippets

Study design

This study investigated, for the first time, pollutant concentrations inside and outside school buildings at different locations in Aveiro, Portugal. Comfort parameters (temperature, relative humidity, CO2 and CO), microorganisms, NO2, VOCs and PM10 concentrations in two elementary schools (city centre and suburban location) were measured between April and June 2010.

Aveiro is a coastal city with approximately 60,000 inhabitants. It is situated on the shores of a coastal lagoon. An industrial

Comfort parameters, gaseous pollutants and microorganisms

The indoor average temperatures during the occupation periods were very similar in both schools: 23 ± 0.6 °C (city centre school) and 23 ± 0.5 °C (suburban school). The average values obtained for the relative humidity were 57 ± 2% and 46 ± 3%, respectively, for the city centre and suburban schools. In addition to meteorological specificities during the sampling campaigns in each school, this small difference may be related to the better insulation of the more recent building that composes the

Conclusions

Comparison of week day and weekend data demonstrated that school activity and indoor sources increase loadings of many gas and particle pollutants. Almost all of the identified VOCs showed I/O ratios higher than one, and especially dichloromethane, suggesting the presence of important indoor sources in both schools. The daily profiles of CO2 suggest that the classrooms are inadequately ventilated, which likely favours accumulation of pollutants in indoor air. Vehicle emissions contributed to

Acknowledgements

This project was financially supported by Fundação para a Ciência e a Tecnologia (FCT) through the PTDC/SAU-ESA/65597/2006 project. Priscilla N. Pegas thanks FCT for the Ph.D. scholarship (SFRH/BD/45233/2008). The authors would also like to thank the support of principals, staff and students.

References (73)

  • J. Fick et al.

    Formation of oxidation products in a ventilation system

    Atmospheric Environment

    (2004)
  • H. Fromme et al.

    Chemical and morphological properties of particulate matter (PM10, PM2.5) in school classrooms and outdoor air

    Atmospheric Environment

    (2008)
  • C. Gonçalves et al.

    Organic particulate emissions from field burning of garden and agriculture residues

    Atmospheric Research

    (2011)
  • C. Gonçalves et al.

    Organic compounds in PM2.5 emitted from fireplace and woodstove combustion of typical Portuguese wood species

    Atmospheric Environment

    (2011)
  • C. He et al.

    Contribution from indoor sources to particle number and mass concentrations in residential houses

    Atmospheric Environment

    (2004)
  • L. He et al.

    Measurement of emissions of fine particulate organic matter from Chinese cooking

    Atmospheric Environment

    (2004)
  • Y. Jie et al.

    Do indoor environments influence asthma and asthma-related symptoms among adults in homes? A review of the literature

    Journal of the Formosan Medical Association

    (2011)
  • W. Jo et al.

    Indoor and outdoor bioaerosol levels at recreation facilities, elementary schools, and homes

    Chemosphere

    (2005)
  • S.C. Lee et al.

    Indoor and outdoor air quality investigation at schools in Hong Kong

    Chemosphere

    (2000)
  • J. Mantis et al.

    PM10-bound polycyclic aromatic hydrocarbons (PAHs) in greater area of Athens, Greece

    Chemosphere

    (2005)
  • T. Meklin et al.

    Size distributions of airborne microbes in moisture-damaged and reference school buildings of two construction types

    Atmospheric Environment

    (2002)
  • Y.Y. Naumova et al.

    Gas/particle distribution of polycyclic aromatic hydrocarbons in coupled outdoor/indoor atmospheres

    Atmospheric Environment

    (2003)
  • T. Ohura et al.

    Characteristics of particle matter and associated polycyclic aromatic hydrocarbons in indoor and outdoor air in two cities in Shizuoka, Japan

    Atmospheric Environment

    (2004)
  • C. Oliveira et al.

    Seasonal distribution of polar organic compounds in the urban atmosphere of two large cities from the North and South of Europe

    Atmospheric Environment

    (2007)
  • J.L.M. Rios et al.

    Symptoms prevalence among office workers of a sealed versus a non-sealed building: associations to indoor air quality

    Environment International

    (2009)
  • W. Yang et al.

    Indoor air quality investigation according to age of the school buildings in Korea

    Journal of Environmental Management

    (2009)
  • F.Y. Yip et al.

    Personal exposure to particulate matter among children with asthma in Detroit, Michigan

    Atmospheric Environment

    (2004)
  • C. Alves

    Characterisation of solvent extractable organic constituents in atmospheric particulate matter: an overview

    Annals of the Brazilian Academy of Science

    (2008)
  • M.A. Bari et al.

    Air pollution in residential areas from wood-fired heating

    Aerosol and Air Quality Research

    (2011)
  • P. Blondeau et al.

    Relationship between outdoor and indoor air quality in eight French schools

    Indoor Air

    (2004)
  • P.M.B.L.C. Brown et al.

    Statistics for environmental engineers

    Environmental & Engineering Geoscience

    (2002)
  • M.S. Callén et al.

    Characterization of PM10-bound polycyclic aromatic hydrocarbons in the ambient air of Spanish urban and rural areas

    Journal of Environmental Monitoring

    (2011)
  • J.M. Daisey et al.

    Indoor air quality, ventilation and symptoms in schools

    Indoor Air

    (2003)
  • E. Diapouli et al.

    Indoor and outdoor PM concentrations at a residential environment in the Athens area

    Global Nest Journal

    (2008)
  • M. Elert et al.

    Human exposure pathways

  • K. Eriksson et al.

    Dermal exposure to terpenic resin acids in Swedish carpentry workshops and sawmills

    Annals of Occupational Hygiene

    (2004)
  • Cited by (88)

    View all citing articles on Scopus
    View full text