Investigation of seasonal variations and sources of atmospheric polychlorinated naphthalenes (PCNs) in an urban area

Atmospheric concentrations of 32 polychlorinated naphthalene (PCN) congeners were determined at four sites (i.e., Suburban, Urban 1, Urban 2, and Industrial) in Izmir, Turkey and their possible sources were investigated. Total PCN (Σ32PCN) concentrations ranged between 5.2 (Suburban 1) to 162 pg m−3 (Urban 1) in summer, while in winter, they ranged from 3.7 (Suburban) to 229 pg m−3 (Urban 1). PCN–24/14 was the dominant congener at all sites (contributing 12–27% to Σ32PCNs), followed by PCN–33/34/37, PCN–28/43, PCN–17/25, PCN–23 and PCN–19. Investigation of possible sources indicated that the combustion processes also contribute substantially to atmospheric PCN concentrations in addition to emissions from sources related to historical use of technical mixtures.