This study aimed to identify the exposure levels of traffic air pollutants specifically PM10, benzene, toluene, and xylene (BTX) among traffic policemen and the risks to their respiratory health. A cross-sectional comparative study was conducted among 42 traffic policemen and 42 desk-bound policemen as the exposed and comparative groups respectively. Methods: The questionnaire adapted from the American Thoracic Society for Adult Respiratory Health Disease (ATS-DLD) to obtain socio-demographic and respiratory symptoms data. A spirometer (Chestgraph Hi-105) was used to perform lung function test. A personal air sampling pump was used to measure the personal exposure level to PM10. A Ppbrae 3000 was used to measure the outdoor and indoor concentration of BTX during morning and afternoon peak hours respectively. Results: The mean personal exposure level of PM10 among the traffic policemen was 150.14 ± 130.66 μg/m3 compared to only 84.14 ± 94.11 μg/m3 in the comparative group. The short exposures to BTX at the roadsides were found to be slightly higher in the afternoons than in the mornings. Indoor offices air concentrations were only detectable for benzene while the mornings and afternoons values for toluene and xylene were below the detection limits. A median concentration of benzene documented significantly higher at the selected of sampling roadsides areas (median=0.157 ppm) than indoor office areas (median=0.071 ppm). Conclusion: The respiratory symptoms were significantly higher in the exposed group compared to the comparative group which they were 3.9, 4.1, and 3.5 times more likely to develop cough, wheezing, and breathlessness respectively.
Exposure to PM2.5 from traffic-related air pollution (TRAP) can cause health risk among residents in the urban area. Those who work outdoors are vulnerable to TRAP. PM2.5 from TRAP contain various carcinogenic and mutagenic compounds that can cause genotoxicity to human health. This study indicated that exposure to the higher level of PM2.5 in the urban areas had exhibited an increased in the formation of micronucleus (MN) among respondents. Traf- fic policemen experienced a high concentration of PM2.5 that lead to higher MN frequency compared to the office workers.