Due to increased energy demands from its rapidly growing economy and population, ambient air in Ulaanbaatar, the capital city of Mongolia contains some of the highest reported air particulate matter (APM) concentrations in the world. The purpose of this study is to identify major APM sources. Source apportionment is an elegant and effective way to establish baseline data for mitigation strategies that focus on reducing APM pollution. The Nuclear Research Centre at the National University of Mongolia has been conducting APM pollution studies in Ulaanbaatar since 2004. Results presented here are based on a sampling campaign from June 2008 to May 2009 at two sites in Ulaanbaatar. APM samples were collected on polycarbonate filter, in two size fractions, fine (PM2.5) and coarse (PM10-2.5) particulate matter. Ion beam analysis provided the elemental concentration values and receptor modeling was used to determine the sources contributing to the particulate matter pollution. The results show that the main sources of PM pollution are soil, motor vehicles, coal and wood combustion, with varying contributing amounts at each site. Source contributions to PM2.5 at a residential site were found to be: soil 47%, coal combustion 35%, motor vehicles/road dust 13% and biomass burning 4%. At the residential site it was found that the primary source contributors to PM10-2.5 were soil 71%, coal combustion 10%, and motor vehicles/road dust 19%.Source contributions to PM2.5 at a non-residential site were found to be: coal combustion 92%, motor vehicles/road dust 3%, soil 3% and biomass burning 2%. At the non-residential site it was found that the primary source contributors to PM10-2.5 were: soil 92%, motor vehicle/road dust 5% and coal combustion 3%.
A Bayesian multivariate receptor model for estimating source contributions to particulate matter pollution using national databases
