“…Several methods have been introduced to identify and quantify OC emission sources, such as the use of organic molecular tracers (Simoneit et al, 1999), receptor models (positive matrix factorization, PMF; chemical mass balance, CMB) (Singh et al, 2017;Bove et al, 2014;Marcazzan et al, 2003), and dispersion models (Colvile et al, 2003); however, their reliability is limited by their low atmospheric lifetimes, in turn due to chemical reactivity and highly variable emission factors (Fine et al, 2001(Fine et al, , 2002(Fine et al, , 2004Gao et al, 2003;Hedberg et al, 2006;Robinson et al, 2006). Recently, radiocarbon ( 14 C) analysis has been used as a powerful tool for facilitating the direct differentiation of non-fossilfuel (NF) carbon sources from fossil fuel (FF) sources, because 14 C is completely absent from FF carbon (e.g., diesel and gasoline exhaust, coal combustion), whereas NF carbon (e.g., biomass burning, cooking and biogenic emissions) shows a high contemporary 14 C level (Szidat et al, 2009).…”