Influence of photolysis on source characterization and health risk of polycyclic aromatic hydrocarbons (PAHs), and carbonyl-, nitro-, hydroxy- PAHs in urban road dust

In this study, PAHs and their transformed PAH products (TPPs) in road dust were subjected to UV driven photolysis, then extracted using simultaneous pressurized fluid extraction, analysed Shimadzu Triple Quadrupole GC/MS. The results of the analysis used investigate robustness reliability 14 existing diagnostic ratios (DRs) two newly proposed molecular DRs that are relevant for characterizing sources TPPs. influence photolysis on carcinogenic health risk posed humans by these hazardous pollutants was assessed. findings indicated segregated into stable, moderately stable non-stable classes source characteristics under photolysis. Only DRs, namely, benzo(a)pyrene/benzo(ghi)perylene (BaP/BghiP) total index exhibited consistent stability whilst fluoranthene/(fluoranthene + pyrene) (FRT/(FRT+PYR)) showed moderate stability. naphthalene/1-nitronaphthalene (NAP/NNAP) pyrene/(1-nitropyrene 1-hydroxypyrene) (PYR/(1NPY+HPY)) found be highly reliable post-emission characterization. cross-plots most traffic emissions is primary PAHs, secondary nitro-PAH (NPAH) percent resonance energy thermodynamic does not exert any direct DRs. Adults more vulnerable potential risks as a result TPPs whereas negligible exist children. This study contributes diagnosis TPP thus, regulatory mitigation thereby, promoting enhanced protection human environment.