Comment on "China to achieve blue sky in 16 years, says official" (China Daily, Nov 26)

Sixteen years, I'm afraid, is a long time for reducing air pollution. The air pollution level in Mexico City was even worse than that in Beijing. But the city authorities managed to clear the skies in less than nine years.

Besides, vehicles may not be the only major problem that Beijing faces. Air pollution is also caused by industries, power plants and families that use coal, wood or charcoal for cooking and heating.