China tells US to stop tweets on Beijing's bad air

China told foreign embassies on Tuesday to stop publishing their own reports on air quality in the country, escalating its objections to a popular US Embassy Twitter feed that tracks pollution in smoggy Beijing.

Only the Chinese government is authorised to monitor and publish air quality information and data from other sources may not be standardized or rigorous, Wu Xiaoqing, a vice environmental minister, told reporters.

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. But its past objections were raised quietly. US consulates in Shanghai and Guangzhou also post readings of the cities’ air quality on Twitter. The feeds were operating normally on Tuesday, and an embassy spokesman in Beijing said the air quality reports were meant to inform Americans living in the three Chinese cities.

The air quality readings in Beijing are based on a single monitoring station within embassy grounds, and pollution levels are rated according to a US Environmental Protection Agency standard that is more stringent than the one used by the Chinese government.

For instance, the US Embassy on Tuesday reported 47 micrograms of fine particulate matter — particulate matter less than 2.5 micrometers in size, or about 1/30th the width of an average human hair — in the air and said the level was “unhealthy for sensitive groups.”
Readings from Beijing Environmental Protection Bureau ranged between 51 to 79 micrograms but categorised all those levels as “good”.