MONTHLY VA IATIONS AND CHEMICAL COMPOSITIONS OF PM1 AND PM2.5 DURING THE HEATING PERIOD IN HARBIN, CHINA

In order to investigate monthly variations and chemical compositions of atmospheric particulates during the heating period, PM1 and PM2.5 particulates were sampled and analyzed, including the characteristics of size distributions and mass concentrations of metal elements and ions. In addition, the sources of metal elements in PM1 were analyzed by the Enrichment Factor (EF). The results showed that the mass concentrations of As, B a, Cr, Cu, Zn, Mn, Ni, Pb, Sr, and Ti ranged from 0.018 to 0.8 mu g/m(3), while Ni was not detected in December. The mass concentrations of Al, Ca, Fe, K, Mg, and Na ranged from 0.4 to 12.5 mu g/m(3), in which the concentrations of Na and Ca were much higher, with the values of 9.091 and 12.131 mu g/m(3), respectively. The characteristics of size distributions showed that the metal elements accounted for 56%-97% of the total mass of PM1, which indicated that the metal elements were mainly enriched in ultrafine particles. The variations of ions in PM1 and PM2.5 were the same. The total mass concentrations of 9 ions in PM1 and PM2.5 were from 30.5 mu g/m(3) to 60.9 mu g/m(3) and from 38.7 mu g/m(3) to 78.0 mu g/m(3) respectively during the heating period. The mass concentrations of S0(4)(2-) and NO3- were higher than other ions, and that of Mg2+ and F- were lower between 0.1 mu g/m(3) and 0.95 mu g/m(3). Enrichment factor analysis suggested that the EF values of the metal elements except Mn and Ti were more than 10, and they were primarily emitted from anthropogenic sources including coal combustion, burning straw, automobile exhaust and fireworks. The EF values of As, Pb were about 1000 which were mainly from fossil fuel combustion. It also showed that the combustion of coal and other fossil fuels during the heating period was the main reason for the increase of some heavy metal elements.