In this study we aimed to evaluate the relationship between individual total exposure to air pollution (AP) and airways changes in a group of 51 wheezing children. Respiratory status was assessed four times (January 2006, June 2006, January 2007, June 2007) during one week, through a standardized questionnaire, spirometry, FeNO and pH in EBC. Concentrations of PM10, O3, NO2 and volatile organic compounds were estimated through direct measurements with an ad hoc device or AP modelling in the children's schools and at their homes in the same 4 weeks of the study. For each child, total exposure to the different air pollutants was estimated as a function of pollutants concentrations and daily activity patterns. Increasing total exposure to PM10, NO2, benzene, toluene and ethylbenzene was associated significantly with a decrease of FEV1 and with an increase of ΔFEV1. Increasing exposure to NO2 and benzene was also related to a significant decrease of FEV1/FVC. Increasing exposure to PM10, NO2, benzene and ethylbenzene was associated with acidity of EBC. This study suggests an association in wheezing children between airways changes and total exposure to air pollutants as estimated by taking into account the concentrations in the various microenvironments attended by the children.