(http://msnbcmedia.msn.com/j/MSNBC/Components/Photo/_new/130113_world_china_smog_stry_230a.photoblog600.jpg)Jason Lee / ReutersMicroscopic pollutant particles in the air have killed some 8,600 people prematurely in 2012. This image shows traffic in Beijing, Saturday.By David Stanway, ReutersBEIJING - Air quality in Beijing was the "worst on record" on Saturday and Sunday, according to environmentalists, with pollution 30-45 times above the recommended safety levels.
With a thick smog wrapping the Chinese capital since Friday, the city's pollution monitoring center warned the city's 20 million residents to stay indoors.
Data posted on Sunday by the monitoring center showed particulate matter measuring less than 2.5 micrometers in diameter (PM2.5) had reached more than 600 micrograms per square metre at some monitoring stations in Beijing, and was as high as 900 on Saturday evening.
The recommended daily level for PM2.5 is 20, according to the World Health Organisation. Such pollution has been identified as a major cause of asthma and respiratory diseases.
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