Identification of wintertime carbonaceous fine particulate matter (PM2.5) sources in Kaunas, Lithuania using polycyclic aromatic hydrocarbons and stable carbon isotope analysis

The study aimed at demonstrating the application of PAHs and δ13C indoor and outdoor measurements towards resolving airborne carbonaceous particle sources in wintertime. Concurrent outdoor and indoor measurements of PM2.5 and size-resolved (PM0.056-2.5) particulate matter were conducted at 6 one-family houses in Kaunas, Lithuania during January–March 2013. PM2.5 and size-resolved filter samples were analyzed for total carbon (TC) and stable carbon isotopic composition by elemental analyzer connected to isotope ratio mass spectrometer. Moreover, the indoor-outdoor concentrations of 10 selected polycyclic aromatic hydrocarbons (PAHs) in PM2.5 were quantified.