(Reuters) - Visibility in Hong Kong has deteriorated so sharply over the last 50 years because of air pollution that variations in levels can even be used to predict mortality rates, health experts warned Wednesday. Visibility is now 12.6 km (7.8 miles) on an average day, well below that of cities such as Paris, Berlin, Auckland and Vancouver, where visibility stands at 20 to 25 km or beyond.
Using government data, researchers at the University of Hong Kong found that the number of hazy days when visibility fell to below 8 km shot up to 54 in 2007 from 6.6 in 1968. For every 6.5-km reduction in visibility, there was a corresponding 1.13 percent increase in the number of non-accidental deaths, such as from heart and respiratory causes. These additional deaths worked out to a total of 1,200 per year between 2007 and 2010, the experts told a news conference.
"Loss of visibility is a direct measure of serious harm to health. Loss of visibility kills people," said Anthony Hedley, Honorary Professor at the School of Public Health. Professor Lam Tai-hing, director of the School of Public Health, said: "The less you can see, the greater the harm. It is very important to believe in your eyes because at the moment, the government is still using outdated air quality objectives.
"Based on that, people are being told today's air quality is good or acceptable when in fact, if you follow the World Health Organization's air quality guidelines, it is very bad indeed."
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