Distribution Characteristics of Polycyclic Aromatic Hydrocarbons in Environmental Media in Nanning City

Abstract

In order to understand the contamination characteristics of polycyclic aromatic hydrocarbons in different environmental media, the authors collected samples of air, atmospheric dry and wet depositions, soil and groundwater in winter and summer in Nanning, using component spectra of 16 kinds of polycyclic aromatic hydrocarbons, combining with the physical and chemical properties, analyzed concentration, composition and distribution characteristics of the PAHs in different environment media, the results showed that PAHs with 2 to 3 rings were dominant in the air and atmospheric dry and wet depositions, and ∑ PAHs in winter were higher than in summer because of the seasonal differences. And PAHs with 2 to 3 rings were dominant in soil, too. Distribution difference of soil particle diameter was the main reason for the PAHs distribution characteristics in different horizons. And species of PAHs in groundwater were fewer, with lower concentrations, which showed that soil vadose zone could entrap more PAHs. The mass fraction of 16 kinds of polycyclic aromatic hydrocarbons in different environmental media presented a decreasing trend from low rings to high rings, and the distribution characteristics of PAHs with 2 to 3 rings and 5 to 6 rings in different environmental media in two areas in winter and summer had good consistency, but also had certain differences because of the physical and chemical properties of PAHs, hydro-geological conditions, urban pollution, weather conditions, etc.