Assessment of indoor environment in Paris child day care centers Ce ´ lina Roda a , Sophie Barral b , Hanitriniala Ravelomanantsoa b , Murielle Dusse ´ aux b , Martin Tribout b , Yvon Le Moullec b , Isabelle Momas a,c,n a Universite´ Paris Descartes, EA 4064-Laboratoire Sante ´ Publique et Environnement, Paris, France b Mairie de Paris, Direction de l 0 Action Sociale de l 0 Enfance et de la Sante´, Laboratoire d 0 Hygi  ene de la Ville de Paris, France c Mairie de Paris, Direction de l 0 Action Sociale de l 0 Enfance et de la Sante´, Cellule Cohorte, Paris, France article info Article history: Received 26 January 2011 Received in revised form 16 June 2011 Accepted 23 June 2011 Available online 23 July 2011 Keywords: Allergen Child day care center Endotoxin Formaldehyde Volatile organic compounds abstract Background: Children are sensitive to indoor environmental pollution. Up until now there has been a lack of data on air quality in child day care centers. Objectives: The aim of this study is to document the indoor environment quality of Paris child day care centers by repeated measurements, and to compare pollutant levels in child day care centers with levels in Paris dwellings. Methods: We selected 28 child day care centers frequented by a random sample of babies who participated in the PARIS birth cohort environmental investigation, and visited the child day care centers for one week twice in one year. Biological contaminants assessed were fungi, endotoxin, dust mite allergens, and chemical pollutants: aldehydes, volatile organic compounds and nitrogen dioxide (NO 2 ). Relative humidity, temperature, and carbon dioxide levels were measured simultaneously. A standardized questionnaire was used to gather information about the buildings and their inhabitants. Results: Airborne endotoxin levels in child day care centers were higher than those found in Paris dwellings. Dust mite allergens in child day care centers were below the threshold level for sensitization in the majority of samples, and in common with dwelling samples. Penicillium and Cladosporium were the most commonly identified genera fungi. The child day care center indoor/outdoor ratio for most chemical pollutants was above unity except for NO 2 , the levels for NO 2 being significantly higher than those measured in homes. Conclusion: Chemical and biological contamination in child day care centers appears to be low, apart from endotoxin and NO 2 . Failure to take child exposure in child day care centers into account could result in an overestimation of children’s exposure to other pollutants. & 2011 Elsevier Inc. All rights reserved. 1. Introduction Indoor environment quality is an increasing public health concern due to the amount of time spent indoors (70–90%), and the presence of chemical and biological contaminants liable to damage respiratory health. This particularly affects young chil- dren who are more vulnerable to pollutants due to their growth, the immaturity of their organs, and the development of their immune system (Salvi, 2007). Whilst the impact of biological contamination on respiratory health is well documented, the impact of chemical pollutants is more equivocal (Franklin, 2007). Several studies have for instance shown that early exposure to house dust mites is a major cause of allergic sensitization and asthma. Platts-Mills et al. (1992) proposed a sensitization threshold of 2 mg/g of dust. Exposure to fungi can cause disease via three defined mechanisms: immune response (allergy), infection, and toxic-irritant effects by particu- lar products generated (mycotoxins, 1,3-b-D-glucan, microbial volatile organic compounds) (Bush et al., 2006). Domestic expo- sure to high endotoxin levels is associated with wheezing in childhood (Gillespie et al., 2006), but protects against the devel- opment of atopic disease in young children (Gehring et al., 2001; von Mutius et al., 2000). Although it has been established that aldehydes and volatile organic compounds (VOCs) can induce irritations, their impact on the incidence of respiratory and allergic diseases in infants is still being questioned (Diez et al., 2000; McGwin et al., 2010; Raaschou-Nielsen et al., 2009; Tavernier et al., 2006). To assess infants 0 exposure to indoor pollutants, it is important to consider each microenvironment they attend. In recent decades many studies have been carried out in infant 0 s dwellings to identify pollutants, document their levels, and determine which factors influence these levels. The infant 0 s dwelling is not Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/envres Environmental Research 0013-9351/$ - see front matter & 2011 Elsevier Inc. All rights reserved. doi:10.1016/j.envres.2011.06.009 n Corresponding author at: Laboratoire Sante ´ Publique et Environnement – EA 4064, Faculte ´ des Sciences Pharmaceutiques et Biologiques, 4 avenue de l 0 Observatoire, 75006 Paris. France. Fax: þ33 1 43 25 38 76. E-mail address: isabelle.momas@parisdescartes.fr (I. Momas). Environmental Research 111 (2011) 1010–1017