Polycyclic aromatic hydrocarbons (PAHs) and their alkylated, nitrated and oxygenated derivatives in the atmosphere over the Mediterranean and Middle East seas

Abstract. Polycyclic aromatic hydrocarbons (PAHs) and their alkylated (RPAHs), nitrated (NPAHs) oxygenated (OPAHs) derivatives are air pollutants. Many of these substances long-lived, can undergo long-range atmospheric transport adversely affect human health upon exposure. However, the occurrence fate pollutants have hardly been studied in marine atmosphere. In this study, we report concentrations over Mediterranean Sea, Red Arabian Gulf Oman Gulf, determined during AQABA (Air Quality Climate Change Basin) project, a comprehensive ship-borne campaign summer 2017. The average ?26PAHs, ?19RPAHs, ?11OPAHs ?17NPAHs, gas particulate phases, were 2.99 ± 3.35 ng m?3, 0.83 0.87 0.24 0.25 m?3 4.34 7.37 pg respectively. Sea region was cleanest for all substance classes, with among lowest ever reported. Over found highest burden ?26PAHs ?11OPAHs, while ?17NPAHs most abundant (known also as Persian Gulf). 1,4-Naphthoquinone (1,4-O2NAP) followed by 9-fluorenone 9,10-anthraquinone OPAHs samples. NPAH composition pattern varied significantly across regions, 2-nitronaphthalene (2-NNAP) being NPAH. According to source apportionment investigations, main sources PAH ship exhaust emissions, residual oil combustion continental pollution. All NPAHs except 2-nitrofluoranthene (2-NFLT), which frequently detected campaign, showed elevated fresh shipping emissions. contrast, 2-NFLT 2-nitropyrene (2-NPYR) highly aged emissions due secondary formation. Apart from 2-NPYR, benz(a)anthracene-7,12-dione 2-NNAP had significant photochemical sources. Another finding that PAHs, sub-micrometre fraction matter (PM1).