Nitro-polycyclic aromatic hydrocarbons - Gas-particle partitioning, mass size distribution, and formation along transport in marine and continental background air

Abstract

Nitro-polycyclic aromatic hydrocarbons (NPAH) are ubiquitous in polluted air but little is known about their abundance in background air. NPAHs were studied at one marine and one continental background site, i.e. a coastal site in the southern Aegean Sea (summer 2012) and a site in the central Great Hungarian Plain (summer 2013), together with the parent compounds, PAHs. A Lagrangian particle dispersion model was used to track air mass history. Based on Lagrangian particle statistics, the urban influence on samples was quantified for the first time as a fractional dose to which the collected volume of air had been exposed. At the remote marine site, the 3-4-ring NPAH (sum of 11 targeted species) concentration was 23.7gpgg'3 while the concentration of 4-ring PAHs (6 species) was 426gpggmg3. The most abundant NPAHs were 2-nitrofluoranthene (2NFLT) and 3-nitrophenanthrene. Urban fractional doses in the range of