Contamination Status of Polycyclic Aromatic Hydrocarbons (PAH s) In Atmospheric Particulate Matter PM2.5 Samples of a Semi-Residential Area of Dhaka, Bangladesh

This study deals with the determination of the polycyclic aromatic hydrocarbons (PAHs) in the atmospheric particulate matters (PM 2.5 ) at a semi residential site of Gazipur, Dhaka, Bangladesh. Source identification and possible human health impact of polycyclic aromatic hydrocarbon was evaluated as well. A total of 20 samples were collected in six weeks period of time. Polycyclic Aromatic Hydrocarbons (PAH’s) were determined using gas chromatography-mass spectrometry. The average concentration of Anthracene, Phenanthrene, Pyrene, Chrysene, Benzo (a) anthracene, Benzo(a)pyrene, perylene were found to be 0.309, 0.159, 0.227, 2.120, 1.954, 2.269 and 3.373µgm -3 respectively. Two-way ANOVA test revealed that the concentration of different PAHs species (F cal > F crit ) are significantly different from each other at a 95% confidence level. The main contributory sources for PAHs were found gasoline exhaust, diesel exhaust, wood burning and brick kilns. The result revealed that these compounds are present in a higher level in the atmosphere when compared with the value of other countries in the world. Concentration of highly carcinogenic Benzo(a) pyrene was in a range where carcinogenic effect is an immediate threat in case of long-time exposure and hence regular monitoring is suggested.