The World Health Organization says air pollution is up 8 percent around the world and, while rich countries are becoming cleaner for the most part, 98 percent of cities in poor nations failed to reach minimum thresholds for healthy air.
A few residents of China's dirtiest cities can afford to move to cleaner ones, while those with automobiles travel to the countryside to "wash your lungs" — but most rely on cheap, disposable masks.
Dangerous levels of small-particulate matter, primarily the result of coal-burning power plants, is reported in China and India, the world's No. 1 and No. 3 polluters.
A study by researchers from the University of California, Berkeley shows that air pollution in China is linked to the deaths of over four thousand people every day.
A King's College London study found that almost 9,500 people died in the capital from exposure to particulate matter and nitrogen dioxide pollution in 2010.
Technologies that trap harmful particulate matter from power plants and factors might be helping improve China's air quality — but they are a disincentive for transitioning from coal-burning power plants to cleaner energy sources.