Emission of Fine Particulate Matter and Nitrogen Dioxide from Incense Burning in Shrines, Chiang Mai, Thailand

Abstract

 Abstract—The inhalation of fine particles (PM2.5) and nitrogen dioxide (NO2) has been associated with health problems. Incense burning is an important indoor source of these pollutants. This research aims to measure PM2.5 and NO2 emitted from incense burning in shrines on special occasions and during normal periods to assess the indoor air quality changes. PM2.5 samples were collected on Teflon filters using a mini volume air sampler set up inside the shrines, while NO2 samples were collected by tube type passive samplers, set up both indoors and outdoors. When special events were compared with normal occasions, the mean PM2.5 concentrations obtained from 8 and 24 hrs were significantly different (p<0.05). Moreover, their concentrations were significantly higher on Chinese New Year than on other special occasions. In the case of NO2, the concentrations were not different among a variety of special occasions, but were higher than the values measured during the normal periods. Moreover, NO2 concentrations were not found to be significantly different when the indoor and the outdoor values were compared. The values of PM2.5 and NO2 concentrations at both shrines were highest during the Chinese New Year. The main reason for this was clearly the number of visitors, which was related with the amount of incense being burned. Concentrations of NO2 and PM2.5 were well correlated (r = 0.580 - 0.779) in every occasion. It can be concluded that the amount of incense being burned played a significant role in pollutant emissions and the indoor air quality.