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This study is the first attempt to assess the presence of 16 priority polycyclic aromatic hydrocarbons (PAHs) enlisted by the US Environmental Protection Agency in PM 2.5 and PM 10 from industrial areas of Odisha State, India. During 2017-2018, bimonthly sampling of PM 10 and PM 2.5 was carried out for 24 h in the industrial and mining areas of Jharsuguda and Angul in Odisha during the pre-monsoon, monsoon, and post monsoon seasons. Highest mean concentration of ∑ 16 PAHs in PM 2.5 was observed during the post monsoon (170 ng/m 3 ) period followed by pre-monsoon (48 ng/m 3 ) and monsoon (16 ng/m 3 ) periods, respectively. A similar trend of ∑ 16 PAHs was also observed in PM 10 with higher levels observed during post monsoon (286 ng/m 3 ) followed by pre-monsoon (81 ng/m 3 ) and monsoon (27 ng/m 3 ) seasons. Diagnostic ratios and principal component analysis suggested diesel, gasoline and coal combustion as the major contributors of atmospheric PAH pollution in Odisha. Back trajectory analysis revealed that PAH concentration was affected majorly by air masses originating from the northwest direction traversing through central India. Toxic equivalents ranged between 0.24 and 94.13 ng TEQ/m 3 . In our study, the incremental lifetime cancer risk ranged between 10 -5 and 10 -3 , representing potential cancer risk., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

3-Aminoquinoline (3AQ) has been used as a fluorescent probe for preferential solvation in hexane-ethanol solvent mixtures. Results of the present experiment have been put into context by comparison with prior observations with 5-aminoquinoline (5AQ) as the probe. 3AQ exhibits a relatively small change of dipole moment (Δ μ = 2.2 D) upon photoexcitation, compared to 5AQ (Δ μ = 6.1D), which might appear to be a hindrance in the way of its use as a solvation probe. Indeed, the values of parameters like spectral shifts are smaller for the present experiment with 3AQ. At the smallest concentration of alcohol used, its local mole fraction around the probe is significantly lower than in the previous experiments with 5AQ. However, these apparent disadvantages are outweighed by the significant increase in fluorescence intensity and lifetime observed with increasing concentration of ethanol in the solvent mixture, as opposed to the drastic fluorescence quenching that occurs for 5AQ. This is a marked advantage in the use of 3AQ in studies like the present one. The local mole fraction of ethanol and preferential solvation index experienced by 3AQ are in line with those reported for 5AQ. The disadvantage of the smaller magnitude of Δ μ persists in the time resolved fluorescence experiments, for solvent mixtures with very low ethanol content. Negligible wavelength dependence of fluorescence transients of 3AQ is observed for x p = 0.002,. However, this effect is outweighed at higher alcohol concentrations, for which nanosecond dynamics of preferential solvation is observed., (© 2022 IOP Publishing Ltd.)