Despite intensive research over the past three decades, a generally accepted standard method to measure black carbon (BC) or elemental carbon (EC) still does not exist. Data on BC and EC concentrations are method specific and can differ widely. This work was motivated by the lack of any prior study that established the variability between these two measures of carbonaceous particulate matter. Measurements of BC and EC were performed at different locations across Asia and the South Pacific in both urban and suburban locations. Filter samples were collected during the winter of 2007 to the winter of 2010 and analyzed for both BC and EC. EC was measured using the Interagency Monitoring of Protected Visual Environments (IMPROVE_A) protocol. Black carbon was measured by the EELS reflectometer (Diffusion Systems, Ltd). Bangladesh had the highest correlation coefficient of 0.93. Bangkok, Thailand on the other hand had the lowest correlation coefficient of 0.34. A review of previously reported source apportionment of BC concentrations in these locations showed that New Zealand had the highest percentage (82%) of BC from biomass while Mongolia had the lowest percentage of 3.1%. The fraction of BC emissions from diesel vehicles was found predominant in Mumbai, India with values as high as 80%. Mongolia had the lowest emission of BC from diesel vehicle (5.4%) with coal-and biomass-combustion being the dominant sources.
BackgroundAir pollution is a major health challenge worldwide and has previously been strongly associated with adverse reproductive health. This study aimed to examine the association between spontaneous abortion and seasonal variation of air pollutants in Ulaanbaatar, Mongolia.MethodsMonthly average O3, SO2, NO2, CO, PM10 and PM2.5 levels were measured at Mongolian Government Air Quality Monitoring stations. The medical records of 1219 women admitted to the hospital due to spontaneous abortion between 2009–2011 were examined retrospectively. Fetal deaths per calendar month from January-December, 2011 were counted and correlated with mean monthly levels of various air pollutants by means of regression analysis.ResultsRegression of ambient pollutants against fetal death as a dose–response toxicity curve revealed very strong dose–response correlations for SO2 r > 0.9 (p < 0.001) while similarly strongly significant correlation coefficients were found for NO2 (r > 0.8), CO (r > 0.9), PM10 (r > 0.9) and PM2.5 (r > 0.8), (p < 0.001), indicating a strong correlation between air pollution and decreased fetal wellbeing.ConclusionThe present study identified alarmingly strong statistical correlations between ambient air pollutants and spontaneous abortion. Further studies need to be done to examine possible correlations between personal exposure to air pollutants and pregnancy loss.
Environmental pollution of the air, water, and soil comprise an increasingly urgent challenge to global health, well-being, and productivity. The impact of environmental pollution arguably has its greatest impact across the lifespan on children, women of childbearing age, and pregnant women and their unborn children, not only because of their vulnerability during development, but also because of their subsequent longevity. Ulaanbaatar, Mongolia, is a highly instructive, perhaps extreme, example of what happens with recent, rapid urbanization. It is the coldest capital city on Earth, where average ambient temperatures routinely fall below -40°C/F between November and February. During the cold winter period, more than 200,000 "Gers" (traditional felt-lined dwellings) in the "Ger district" burn over 600,000 tons of coal for domestic heating (>3 tons each). Thus, outdoor ambient particulate levels frequently exceed 100 times the WHO-recommended safety level for sustained periods of time, and drive the majority of personal particulate matter exposure. Indoor levels of exposure are somewhat lower in this setting because Gers are equipped with chimneys. Major adverse health impacts that we have documented in the Ger districts include the following: respiratory diseases among those between 1 and 59 years of age and cardiac diseases in those over 60; alarming increases in lung cancer rates in females are also beginning to emerge; and fertility and subsequent successful completion of term pregnancy falls by up to half during the winter pollution season, while early fetal death rises by fourfold. However, the World Bank has intervened with a Ger stove replacement project that has progressively reduced winter pollution by about 30% over the past 5 years, and this has been accompanied by an increase in mean term birth weight of up to 100g. Each incremental decrement in air pollution clearly has beneficial effects on pregnancy, which are likely to have the greatest positive health and macroeconomic impact across the lifespan. However, innovative policies and solutions are clearly needed to eliminate coal heating in Gers and thus further reduce the markedly negative health impact of this practice.
The capital city of Mongolia, Ulaanbaatar, suffers from high levels of pollution due to excessive airborne particulate matter (APM). A lack of systematic data for the region has inspired investigation into the type, origin and seasonal variations of this pollution, the effects of meteorological conditions and even the time-dependence of anthropogenic sources. This work reports source apportionment results from a large data set of 184 samples each of fine (PM 2.5 ) and coarse (PM 2.5-10 ) fraction atmospheric PM collected over a three-year period (2014)(2015)(2016) in Ulaanbaatar, Mongolia. Positive Matrix Factorization (PMF) was applied using the concentrations of 16 elements measured by an energy dispersive X-ray fluorescence spectrometer along with the black carbon content measured by a reflectometer as input data. The PMF results revealed that whereas mixed sources dominate the coarse fraction, soil and traffic sources are the principle contributors to the fine fraction. The source profiles and the seasonal variations of their contributions indicate that fly ash emanating from coal combustion mixes with traffic emissions and resuspended soil, resulting in variable chemical source profiles. Four sources were identified for both fractions, namely, soil, coal combustion, traffic and oil combustion, which respectively contributed 35%, 16%, 41% and 8% to the coarse fraction and 31%, 27%, 31% and 11% to the fine fraction. Additionally, the probable source contributions from long-range transport events were assessed via concentration-weighted trajectory analysis.
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%.
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