A comprehensive review on occurrence, source, effect, and measurement techniques of polycyclic aromatic hydrocarbons in India

Monitoring organic pollutants, including polycyclic aromatic hydrocarbons (PAHs), has been of global concern due to their widespread occurrence in multi-components of the environment. In this study, we critically reviewed 20 years of published literature to examine the occurrence of PAHs, sources, and their toxicological effect in the multimedia environment of India, with particular emphasis on analytical techniques. After review, we found the ubiquitous presence of PAHs in the Indian condition. The distribution of PAH is highly heterogeneous, with maximum concentration in coastal sediments from Bhavnagar in Gujrat. Nonetheless, PAH has not been inves-tigated in all locations/matrices of India, especially highly urbanized areas, metropolitan cities, and industrial zone, demanding organized monitoring of PAHs. Gas chromatography coupled with flame ionization detector, mass spectrometry detector (GC-FID/GC-MS) and high-performance liquid chromatography coupled with ultraviolet-visible sensor (HPLC-UV) is currently employed for PAH analysis. The usage of more sensitive and advanced techniques such as high-resolution MS (HRMS), Fourier transform infrared (FTIR) spectrometry, and quadrupole time of flight (QTOF) can offer accurate identification of PAHs. The positive matrix factorization (PMF) source apportionment analysis indicated residential coal combustion, vehicular emission, and biomass burning as the primary sources of PAHs pollution. Exposure to PAHs is associated with many adverse effects in humans, including carcinogenicity, teratogenicity, genotoxicity, and endocrine-disrupting effects. Finally, we have highlighted the significant research gaps and suggested recommendations for future work based on our critical review.