Effects of Atmospheric Pollutants on Children Asthma Outbreaks

ABSTRACT

The effects of air pollutants, weather conditions, airborne pollen and spores on the incidence of emergency room (ER) visits of children for acute asthma attacks were investigated.

One-year retrospective study was done. Data on daily concentrations of air pollutants, airborne allergens and weather conditions were collected and compared with the ER visits of 2431 asthmatic children (age 1-18 years) in the Schneider Medical Center, near Tel Aviv.

ER visits of asthmatic children showed a negative correlation with the measured O3 concentrations and with extreme ambient temperatures. A positive correlation was found with high barometric pressure with NO2 and SO2 concentrations. An exceptionally high incidence of ER visits of asthmatic children was observed during September, coinciding with the beginning of the school year. When September was excluded from the annual calculations the correlation between ER visits and environmental factors increased. 49% of the variance of ER visits were explained by O3 alone, 46% by NO2 alone, 54% by O3+NO2, and 31% by weather parameters. 58% of the variation was explained by the combination of air pollutants and weather parameters. Airborne particulates did not show any meaningful correlation with ER visits.

The major factors associated with severe asthma attacks were high NO2 and SO2. The negative correlation with O3 implies that at certain concentrations, O3 may have a beneficial effect. The particularly high number of ER visits at the beginning of the school year was presumably associated with an increase in viral infections combined with emotional stresses.