Photos: Fog or smog? Pollution at dangerous levels in China
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Credit: Getty Images
BEIJING, CHINA - JANUARY 29: A men rides a bicycle as tourists waiting the flag-raising ceremony during severe pollution at Tiananmen Square on January 29, 2013 in Beijing, China. The 4th dense fog envelops Beijing with pollution at hazardous levels in January. (Photo by Feng Li/Getty Images)
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