Acute effects of particulate matter on respiratory diseases, symptoms and functions:: epidemiological results of the Austrian Project on Health Effects of Particulate Matter (AUPHEP)

To examine hypotheses regarding health effects of particulate matter, we conducted time series studies in Austrian urban and rural areas. Of the pollutants measured, ambient PM2.5 was most consistently associated with parameters of respiratory health. Time series studies applying semiparametric generalized additive models showed significant increases of respiratory hospital admissions (ICD 490-496) at age 65 and older. The early increase of 5.5% in Vienna at a lag of 2 days in males and of 5.6% per 10 μg/m3 at a lag of 3 days in females was not observed in a nearby rural area. Another increase of respiratory admissions (mainly COPD) was observed after a lag of 10–11 days. A time series on a panel of 56 healthy preschool children showed a significant impact of the carbonaceous fraction of PM2.5 on tidal breathing pattern assessed by inductive plethysmography. In repeated oscillometric measurements of respiratory resistance in 164 healthy elementary school children not only immediate responses to fine particulates were found but also latent ones, possibly indicating inflammatory changes in airways. It may be speculated that the improvements of urban air quality prevented measurable effects on respiratory mortality. More sensitive indicators, however, still show acute impairments of respiratory function and health in elderly and children which are associated with fine particulates and subfractions related to motor traffic.