ABSTRACT

Ulaanbaatar, the capital city of Mongolia, is subjected to heavy atmospheric pollution especially in winter. In order to clarify inorganic and organic chemical characteristics of suspended particulate matters (SPMs) and contribution degrees of SPM sources throughout the year, 53 SPM samples collected during January 2014 to April 2015 at central part of Ulaanbaatar were analyzed for total carbon, total hydrogen, water soluble cations and anions, metal elements, and aliphatic and polycyclic aromatic hydrocarbons (n-alkanes and PAHs, respectively). The SPMs collected in the cold season (November to March) show high concentrations of many chemical species, such as total carbon and hydrogen, water soluble ions, n-alkanes and PAHs. The SPMs in the cold season are concluded to be harmful for human health, because of high concentrations of carcinogenic As and PAHs up to 45 and 8.8~13 ng/m³, respectively. Principal component analysis of chemical species suggests that SPMs in Ulaanbaatar can be explained mostly by 2 components; coal and biomass combustion (about 70%) and soil dusts (about 15%). However, we could not quantitatively discriminate the contribution degrees of coal burning at thermal power plants and coal and biomass burning at households in the Ger (traditional Mongolian dwelling houses) area. Direct analyses of carbonaceous ashes adhering to tunnels of power plants and Ger houses must be indispensable for determination of contribution degrees of these sources.