ESTIMATING THE MORTALITY EFFECTS OF PARTICULATE MATTER IN BANGKOK, THAILAND

ABSTRACT:

Air pollution data in Bangkok, Thailand indicate that levels of PM10 are significantly higher than in most cities in North American and Western Europe, where its health effects are well-documented. However, the pollution mix, seasonality and demographics are different from those in developed Western countries. It is important, therefore, to determine whether the large metropolitan area of Bangkok is subject to similar effects of PM10.

The main objective of this study was to investigate the mortality risk from air pollution in Bangkok, Thailand. The study period extended from 1999 to 2003, for which the Ministry of Public Health provided the mortality data. Measures of air pollution were derived from air monitoring stations, while information on temperature and relative humidity was obtained from the weather station in central Bangkok. The statistical analysis followed the common protocol for the multi-city PAPA project in using a natural cubic spline model with smooths of time and weather.

The results indicated that excess risk for non-accidental mortality was 1.3% (95% CI, 0.8-1.7) per 10 g/m3 of PM10 , with higher excess risks for cardiovascular and respiratory mortality of 1.9% (95% CI, 0.8-3.0) and 1.0% (95% CI, -0.4-2.4), respectively. In addition, the effects from PM10 appear to be consistent in multi-pollutant models. This suggested strong associations between several different mortality outcomes and PM10. In many cases the effect estimates were higher than those typically reported in Western industrialized nations.