Impact of Seasonal Winter Air Pollution on Health across the Lifespan in Mongolia and Some Putative Solutions

Abstract

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.

Keywords: Mongolia; air pollution impact; lifespan; mothers and children.

Figure 1.

Distribution of Ger districts, predominantly in the northern suburbs of Ulaanbaatar. Satellite view of greater Ulaanbaatar surrounded by snow (white). The centrally built environment that houses 40% of the total population in apartments is shown in gray. The surrounding dark green areas show the extent of the Ger districts that house the remaining 60% of the total Ulaanbaatar population of 1.5 million. The northern Ger districts contain approximately 200,000 family units, each living in a Ger and/or adjacent wooden shanties.

Figure 2.

A single Ger out on the steppe in summer (top), as compared with a small section of the northern Ger district in Ulaanbaatar in winter (bottom). Note how closely packed the round Gers are in the foreground. Also note the thick pall of coal smog hanging over the Ger district and bounded to the north by snowcapped mountains.

Figure 3.

Top: Annual seasonal air pollution. The relative black carbon particulate matter concentrations in central Ulaanbaatar (UB) are depicted as maximum (red), minimum (dark blue), mean (green), and median (mauve). Hours of daylight is depicted in light blue. Black carbon units are expressed as nanograms per cubic meter. Bottom: Intradiurnal black carbon pollution levels. Each curve represents one individual day. Days were recorded over the course of one year and are superimposed to display patterns of diurnal variation over the course of one year. The bimodal distribution of black carbon pollution with separate peaks in the morning and evening is well illustrated. Data in the upper and lower panels are used by generous and gracious permission of Christa Hassenkopf and were recorded in the climate laboratory of Prof. Sereeter Lodoysamba at the National University of Mongolia. The figure was prepared by Nicole Warburton using these data.