Air pollution and restricted activity days among New Zealand school children and staff

Particulate Matter (PM) air pollution has been associated with a variety of adverse health effects. However, the influence of exposure to particulate pollution on non-notifiable health outcomes such as individual-level restricted activity is less well understood. Days absent from work or school were collected for 2257 students and teachers at eight secondary schools in Christchurch, New Zealand. Mean levels of PM10 (PM less than 10 micrometers in diameter) for the study period were 42.7 mu g m(-3) at schools and 48.9 mu g m(-3) at a centrally located monitoring site. A significant (p < 0.05) association between PM10 and restricted activity days was found at schools for same-day and 1-day lags. The results presented in this paper suggest that there is a positive association between restricted activity and particulate matter air pollution even though the associations were not consistently statistically significant.