Uncharted sources of particle bound polycyclic aromatic hydrocarbons from South Asia: Religious/ritual burning practices

This paper deals with the real–world emissions of particle bound polycyclic aromatic hydrocarbons (PAHs) emitted from different religious and ritual burning practices in India. The emission factors (EFs) of various PAHs were characterized over integrated stages of burning practices including pyrolysis, flaming and smoldering. Sampling was carried out in selected five different types of religious and ritual places: Hindu Temples (HT), Muslim Holy shrines (MG), Buddhist Temples (BT), Hindu Marriage Places (MP) and Cremation Centers (Hindu Funeral Pyre) (CC); where burning practices mostly include natural and synthetic biomaterials in different proportions. Seventy PAHs were analyzed and grouped in light PAHs (LPAHs=25) and heavy PAHs (HPAHs=45) according to number of benzene rings present and respective molecular weights. The average EF of total PAHs (TPAHs) from MP, MG, BT, HT and CC is estimated as 77.04 ± 5.39, 99.09 ± 6.02, 90.35 ± 6.76, 22.78 ± 1.57, and 77.15 ± 6.16 mg kg−1, respectively. Country level emission budget of particulate bound TPAHs from religious and ritual burning practices has also been evaluated to 0.47 Gg yr−1; contributed ~23% of the 2.07 Gg yr−1 – Indian emission budget of PAHs from unknown sources reported earlier.