The air in Beijing is filled with 24 times the amount of pollutants deemed safe by the WHO

Chinese officials Sunday declared an “orange” alert, the second highest level after red, and the highest so far this year, as heavy smog has descended on the city, darkening it all, for most of November.

The alert came as readings of the tiny poisonous PM2.5 particles reached into the high 600 micrograms per cubic meter around the city. The World Health Organization's safe level of this particle is 25. Some suburban neighborhoods logged levels up in the 900s Monday, according to The Associated Press.

The alert requires all industrial plants to reduce or shut down production altogether. It also bans heavy-duty trucks from city roads and order construction sites to stop operations .... http://abcnews.go.com