Thick smog enveloped Hong Kong again on Friday, as scientists and campaigners said recent pollution had reached levels ten times above annual World Health Organisation guidelines for clean air.
The heavy haze descended on the city, blocking views across the financial hub's famous Victoria Harbour and raising serious health concerns. The Hedley Environmental Index, a website created by professors at Hong Kong University and think tank Civic Exchange, said levels of breathable particles in some areas were 10 times recommended annual WHO levels on Friday.
Levels of nitrogen dioxide and sulphur dioxide were five times WHO annual guidelines, the index found, making Thursday Hong Kong's most polluted day in more than 12 months.
"This is smog, not fog," said Alexis Lau, a professor at Hong Kong University for Science and Technology. "The worst part is that most of these are fine particulates which are the most detrimental to our health."
Air quality guidelines 'out of date'
According to the government's own air pollution index, levels in the heavily populated areas of Hong Kong were still "very high" on Friday, or well over 100 on the official scale. When the government index is above 100, people with existing heart or respiratory problems are advised to stay indoors.
Hong Kong's government is currently in the process of renewing its air quality guidelines, which are now more than 20 years old. Scientists say they are woefully out of date.
Pollution has in recent years become an increasing health and economic headache for the financial hub. Emissions from the southern Chinese factory belt over Hong Kong's northern border have combined with local emissions from power plants and transport to park a thick haze over the city for large parts of the year.
The Hedley Environmental Index, which combines air quality and public health data, puts the associated costs of the city's poor air at 12.5 billion Hong Kong dollars (1.6 billion US) since the start of 2004. It has, it said, caused more than 6 100 premature deaths. – (Sapa, January 2009)
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