Population-based exposures to NO2 and O3 using only home addresses were compared with models that integrate all time-activity patterns鈥攊ncluding time in commute鈥攆or Flanders and Brussels. The exposure estimates were used to estimate the air pollution impact on years of life lost due to respiratory mortality.
Health impact of NO2 using an exposure that integrates time-activity information was on average 1.2%higher than when assuming that people are always at their home address. For ozone the overall estimated health impact was 0.8%lower. Local differences could be much larger, with estimates that differ up to 12%from the exposure using residential addresses only. Depending on age and gender, deviations from the population average were seen.
Our results showed modest differences on a regional level. At the local level, however, time-activity patterns indicated larger differences in exposure and health impact estimates, mainly for people living in more rural areas. These results suggest that for local analyses the dynamic approach can contribute to an improved assessment of the health impact of various types of pollution and to the understanding of exposure differences between population groups.