Acute and chronic effects of air pollution continue to be a major focus of research for the Respiratory Disease, Exposure Assessment, and Study Design and Statistical Methodology Research Cores. Investigators are only beginning to understand the true relationships of indoor and outdoor pollution with the various forms of respiratory disease. The SCEHSC employs a wide range of approaches to determining the acute and chronic respiratory effects of pollutants on a clinical or epidemiologic scale and several papers have been published on this topic during 2000.

From the Children’s Health Study, a ten-year study aimed at evaluating the long-term effects of air pollution on the respiratory health of children, Gauderman et al. (2000) reported the first longitudinal results suggesting that the common air pollutants – NO2, fine particles, and acid vapor, but not ozone – slow children’s lung function growth rate over time. This is some of the first evidence of a chronic effect of air pollution in children. Since 1993 researchers have tested the lung function of kids in twelve communities with varying levels of air pollution. As the children grow up, those who breathe smoggier air tend to lag in the rate of lung function growth behind children who breathe cleaner air. Over four years, children in the smoggiest communities on average had a lung function growth rate ten percent lower than children in the least polluted communities. The association between air pollution and lung function growth rate is also stronger in children who spend more time outdoors. The results suggest that significant negative effects on lung function growth in children occur at current ambient concentrations of particles, NO2, and inorganic acid vapor. These results corroborate early indications from cross-sectional analyses that NO2, particles and acid vapor are associated with lower lung function. There is also evidence that school absenteeism rises as air pollution worsens. Gilliland et al. (2001) showed that school absences due to sore throats, coughs, asthma attacks and similar problems increase in the three to five days following a significant rise in ozone. Each increase of 20 parts per billion of ozone was found to be associated with an 83% increase in absences due to respiratory illness, a 45% increase for absences due to upper respiratory illnesses and a 174% increase for lower respiratory illness with wet cough. No association was found with exposure to particulate matter or NO2. Increased school absenteeism from O3 exposure in children is an important adverse effect of ambient air pollution worthy of public policy consideration.