Characteristics and Source Apportionment of Water-soluble Inorganic Ions in Road Dust PM2.5 During Spring in Tianjin Using the Quadrat Sampling Method

Abstract

In order to collect comprehensive information regarding the characteristics and sources of the water-soluble inorganic ions in road dust (RD) PM2.5 in Tianjin, samples of road dust were collected in April 2015 in Tianjin, and then re-suspended on filters using a NK-ZXF sampler. The concentrations of the major water-soluble inorganic ions were analyzed by ion chromatography. A correlation analysis, ratio method, and principal component analysis were used to analyze the sources of RD PM2.5. The results showed that the total water-soluble inorganic ion concentration in Tianjin accounted for 6.13%±2.32%, varying with different road types. Na+, K+, Mg2+, and Ca2+ showed high homology. NO3-/SO42- revealed that the main source of PM2.5 was mostly attributed to fixed sources. The principal component analysis showed that the main sources of RD PM2.5 in Tianjin were coal combustion, mobile sources, biomass burning, and construction dust.