On the basis of the results of the SIDRIA-2 study, we estimated the population attributable risk (PAR%) of chronic respiratory disorders in childhood for the exposure to some preventable risk factors (passive smoking-ETS, molds/dampness on the walls of the bedroom, high traffic in the street of residence) and for not preventable risk factors such as parental history of respiratory disorders or allergies. About 27% of respiratory disorders could be attributed to this latter factor, while 15.5% and 18% (among children and adolescents respectively) are potentially avoidable if exposure to ETS, molds in the home and high traffic in the street of residence are avoided.