울산 대기 중 폴리염화나프탈렌의 오염 특성과 위해도

Abstract

The seasonal variation, source apportionment, and inhalation cancer risks of atmospheric polychlorinated naphthalenes (PCNs) were investigated in Ulsan, South Korea. Mean total concentrations of PCNs were 5.03 ± 3.78 pg/m3 in the gaseous phase and 0.29 ± 0.75 pg/m3 in the particulate phase. Tri-CNs (47%) and tetra-CNs (28%) predominated in the gaseous phase, whereas octa-CNs (68%) and hepta-CNs (17%) predominated in the particulate phase. Diagnostic ratios suggested that atmospheric PCNs were primarily influenced by combustion sources. Principal component analysis indicated that re-volatilization from Halowax-related sources was more pronounced in summer. Conditional bivariate probability function analysis revealed that elevated PCN concentrations in summer were driven by local industrial emissions. Concentration-weighted trajectory analysis indicated that long-range atmospheric transport (LRAT) contributed to particulate PCN concentrations during winter and spring, particularly for highly chlorinated congeners with greater toxicity. The annual inhalation cancer risk (1.8 × 10−8) was below the US EPA acceptable risk level. PCNs accounted for 17% of the annual total TEQs and up to 56% in summer when combined with other POPs from the national POP monitoring network. These results demonstrate that atmospheric PCNs from diverse sources, including industrial emissions, re-volatilization, and LRAT, can play an important role in dioxin-like toxicity in ambient air.