Last Updated: Tuesday, June 05, 2012, 23:23
China has long taken issue with the US Embassy`s postings of hourly readings of Beijing`s air quality on a Twitter feed with more than 19,000 followers since 2008.
Last Updated: Wednesday, December 01, 2010, 21:09
About 25% of Hong Kong`s population wants to leave the city to escape its notoriously polluted air.
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