As her seven children scamper in and out of the small door of
their traditional felt hut in Mongolia's capital Ulan Bator,
Narantuya sits over the stove, pouring blocks of black coal onto
the fire. In a city where average winter temperatures hover at a
punishing minus 20 degrees Celsius (minus 4 Fahrenheit), the
stove is the only source of heat for the 39-year-old unemployed
single mother and her children. The family burns through two
bags of coal and half a bag of wood each day to stay warm. But
Narantuya says she still does not understand why the capital is
blanketed in thick smog -- and how she is part of the problem.
"I don't know why it happens but I know it affects my children.
In winter, they are constantly sick with colds and coughs. I'm
always afraid one of them will get a serious illness," the
diminutive woman tells AFP. Despite its population of just one
million people, Ulan Bator is one of the world's most polluted
cities, sparking mounting concern about spiralling health care
costs -- and tough c