Emission sources, Characteristics and risk assessment of particulate bound Polycyclic Aromatic Hydrocarbons (PAHs) from traffic sites

Atmospheric PM2.5 size particulate-associated Polycyclic Aromatic Hydrocarbons (PAHs) were analyzed from December 2018 to May 2019 over three traffic sites of Chota Nagpur Plateau (CNP) of India were analyzed to study their temporal and seasonal variations. Over the last few decades, CNP becomes a hotspot of air pollution due to traffic and anthropogenic activities. The PM2.5 concentration was higher than the value given by the National Ambient Air Quality (NAAQ) standard value. The results show the total average concentration of PAHs was found 141.48±22.86, 163.80 ±30.43, and 171.60±26.23 ng/m3 over site (Adityapur) ADP, (Sakchi) SKI, and Mango (MGO), respectively. The PM2.5 total average concentration was found 67.91± 14.04, 79.70± 13.53, and 103.20± 21.77µg/m3 over site ADP, SKI, and MGO, respectively. Diagnostic ratio analysis reveals that the source of PM2.5 associated with PAHs was petrogenic, pyrogenic, coal combustion, and vehicular emission. Backward trajectories model and fire count data were also used for air parcel movement up to height 4500 m above the earth’s surface. The traffic campaign has provided a rare opportunity for the CNP region for the collection of more air pollution baseline data, which could be helpful in the formulation of air pollution reduction policies in the future