Space-time analysis of the effect of air pollution on children's health.

The study aimed to investigate the short-term association between air pollution and emergency treatments for respiratory diseases in children 0 to 6 years of age. This was an ecological space-time study in Greater Metropolitan Vitória, Espírito Santo State, Brazil. A Poisson regression general additive model (GAM) used the number of daily treatments for respiratory diseases as the dependent variable, and the independent variables were daily concentrations of air pollutants (PM10, SO2, NO2, O3, and CO), temperature, humidity, and precipitation. Average daily concentrations were used to make estimates for the entire metropolitan area and in loco analyses considering children residing in a 2km radius around 8 air quality monitoring stations. An increase of 10μg/m3 in the concentration of air pollutants increased the risk of emergency treatment for respiratory disease. In the overall area, for PM10, the increase was 2.43%, 2.73%, and 3.29% in the cumulative values at 5, 6, and 7 days, respectively. For SO2, the increase was 4.47% on the day of exposure, 5.26% two days later, and 6.47%, 8.8%, 8.76%, and 7.09% for the cumulative values at days 2, 3, 4, and 5 days, respectively. CO showed a significant association for residents around two stations, and O3 for only one. Even within the limits set by the World Health Organization, the pollutants PM10, SO2, NO2, and O3 are associated with increased risk of treatment for respiratory diseases in children 0 to 6 years of age, and some effects were only identified when disaggregating by neighborhood, i.e., in loco, which allows capturing greater variation in the data.