If economic incentives facing producers and consumers do not change with higher incomes, pollution will continue to grow unabated with the growing scale of economic activity.

ECONOMIST: Local difficulties

The environment has moved to the top of their political agenda, and they have promised increased environmental investment, set impressive targets for reducing pollution and launched grand-scale campaigns to address particularly challenging problems of environmental degradation.

CNN: Economic miracle, environmental disaster

Air Pollution Score rates tailpipe emissions for pollutants that cause smog, on a scale of 1 to 10, with 10 being the cleanest and 1 the dirtiest.

FORBES: America's Dirtiest Vehicles 2013