[Respiratory symptoms associated with asthma prevalence and air pollution in preschool children].

Introduction: Increases in the air pollution levels has well-documented harmful effects on human health, especially exacerbating problems of asthma and other allergies.

Objective: The prevalence of symptoms associated with asthma was determined in preschool populations in zones with differing levels of air pollution.

Materials And Methods: A cross-sectional study was conducted in Bucaramanga, Colombia, comparing respiratory symptoms in 768 children under seven years in two urban zones with different pollution levels of particulate matter and ozone.