1989 Volume 24 Issue 3 Pages 234-243
International comparison of carcinogenic/mutagenic compounds in air will provide useful information for the study on the effect of air pollution to health such as lung cancer. The present authors have carried out comparative study on air pollution by polycyclic aromatic hydrocarbons (PAH) among Bangkok, Chiang Mai and Tokyo.
Airborne particulate samples were collected at the following sampling places: 1) 7 air pollution monitoring stations in Bangkok (from Nov., 1985 to Jan., 1986), 2) 8 places in Chiang Mai (from Feb., to Sep., 1986), 3) National Institute of Public Health in Tokyo (from Nov., 1985 to Sep., 1986). Each sampling was done for 24 hrs/sampling-day by using high-volume air samplers. PAHs in particulate samples were extracted by benzene: ethanol=-3: 1 (v/v) with ultrasonic agitation. Extracted solutions were cleaned up by liq.-liq. partition with 5% NaOH aqueous solution and PAH in them were determined by a reversed-phase HPLC/fluorometry.
The geometric average of total aerosol concentrations in Bangkok was 1. 5 times higher than that in Tokyo. However, the average concentrations of pyrene and chrysene in the air were 5. 2 and 9. 4 times higher in Tokyo, respectively. Average concentrations of BaP, BkF and BeP were slightly (1. 2-1. 3 times) higher in Tokyo. In case of BghiP, average concentration in Bangkok was 1. 4 times higher than that in Tokyo. Similar phenomena were observed in the comparison of average data between Chiang Mai and Tokyo. Average concentrations of pyrene and chrysene were 2, 3 times higher in Tokyo, while those of BkF and BeP were only 1. 1-4. 2 times higher in Tokyo. In case BaP and BghiP, average concentrations were 1.2 times higher in Chiang Mai. These phenomena may mainly due to the difference in atmospheric temperature and UV irradiation. Monthly average temperature in Bangkok and Chiang Mai were ranging 25.5-26.7 (ay. 26.1°C) and 23.1-29.0°C (av. 26.7°C), respectively (from 1951 to 1960), which were well higher than that in Tokyo (4.7-26.5°C, ay. 15.3°C from 1951 to 1980). It was also suggested that PAHs tend to be higher during the dry season in Thailand.
