BEIJING ordered government vehicles off the roads as part of an emergency response to ease air pollution that has smothered China's capital for the past three days, while warning the smog will persist until January 16.
Hospitals were inundated with patients complaining of heart and respiratory ailments and the website of the capital's environmental monitoring centre crashed. Hyundai Motor's venture in Beijing suspended production for a day to help ease the pollution, the official Xinhua news agency reported.
Measurements of PM2.5, fine airborne particulates that pose the severest health risks, rose as high as 993 micrograms per cubic metre in Beijing on January 12, compared with World Health Organisation guidelines of no more than 25. It was as high as 500 at 6am on Monday.
Shrouded in haze ... the China Central Television (CCTV) building in Beijing. Photo: Reuters
Long-term exposure to fine particulates raises the risk of cardiovascular and respiratory diseases as well as lung cancer, according to WHO.
''Pollution levels this high are extreme even for Beijing,'' the Beijing head of Greenpeace East Asia's climate and energy campaign, Li Yan, said.
''Although the government has announced efforts to cut pollution, the problem is regional and to fix Beijing's problem, we also have to fix industrial pollution in neighbouring regions like Hebei and Tianjin and even as far as Inner Mongolia.''
Extreme smog ... artist Ai Weiwei donned a gas mask for photos he posted on on Twitter. Photo: AFP
Exposure to PM2.5 helped cause a combined 8572 premature deaths in Beijing, Shanghai, Guangzhou and Xi'an in 2012, and led to economic losses of $US1.08 billion ($1.02 billion), according to estimates in a study by Greenpeace and Peking University's school of public health published on December 18.
''The number of people coming into our emergency room suffering heart attacks has roughly doubled since Friday when the air pollution became really severe,'' the deputy head of cardiology at Peking University People's Hospital, Ding Rongjing, said.
China, which the World Bank estimates has 16 of the world's 20 most-polluted cities, is the largest emitter of greenhouse gases.
On Sunday, Beijing began its emergency-response plan to the pollution, which included ordering government vehicles off the roads to cut usage by 30 per cent, according to Xinhua, citing the director of the city's environmental protection bureau's air quality department, Yu Jianhua.
The plan also calls for construction sites to limit activity that creates large amounts of dust and asks industrial companies to reduce emissions.
Residents are advised to stay indoors and use public transport if they need to go out, while primary schools should reduce outdoor activities, Xinhua said.