In the past three decades, China's development has pulled a staggering 680 million people out of poverty. It did so through a dramatic increase in access to modern energy, mostly powered by coal, which has led to terrible outdoor air pollution in Chinese cities, not to mention making China the world's premier carbon dioxide emitter. That is why many environmentalists say that China's meteoric rise has come at substantial environmental costs.

It is true that China now suffers from more outdoor air pollution than in its pre-boom days, but the same happened in all other industrializing countries - air pollution in London reached a peak in 1890.

It is also important to point out that while outdoor air pollution in China has definitely increased since 1990, the overall impact of air pollution has declined. This is because indoor air pollution is often wrongly ignored. Indoor air pollution comes from burning charcoal, twigs and dung inside the house, which creates terrible pollution and kills more than 1 million people in China each year.