For days now a heavy smog has smothered Beijing. By Saturday afternoon, it was so thick you could see just a few hundred meters in the city center. Tower blocks vanished into the grayness. The air tasted of coal dust and vehicle fumes, two of Beijing’s main sources of pollution. Even indoors the air looked hazy. World Health Organization guidelines say average concentrations of the tinniest pollution particles should be no more than 25 mg/m3. _______________________________________________________________________________________.
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作者: siddhis 时间: 2013-2-26 16:08
Beijing, the pollution level's over 400 by the city's official readings and more than 800 according to US embassy monitoring center
