Thursday, January 24, 2013

Deadly air: the smog shrouding China’s future

by Emilie Parkinson

Beijing has been smothered by a dense and dangerous smog this month, which has set new air pollution records over several days.
The World Health Organization advises that the acceptable level of fine particles in the air measuring less than 2.5 microns – known as PM2.5 – should be no more than 25 micrograms per cubic metre. Above 300, and the United States Environmental Protection Agency warns that outdoor activity becomes “hazardous”, even for healthy adults.
On January 12 this year in Beijing, the PM2.5 pollution hit 886– officially off the charts for dangerous air quality.
But the problem is not limited to Beijing. Many other cities in China have also been suffering from what is described as the worst air pollution in history.
Gasping for breath
I lived in Beijing for 10 years, long enough to give me chronic bronchitis. For years, I was on antibiotics and codeine phosphate solution; occasionally I also suffered from skin problems. It was only after I moved to Australia that my bronchitis gradually began to get better.
One of my friends, now based in Beijing and working for the national television station, also suffers from chronic diseases like rhinitis. She recently told me that her rhinitis has relapsed due to the smoggy air outside – but she has found that her symptoms miraculously vanish when she travels out of Beijing to cities in southern China.
The hazardous smog has created a surge of paediatric and geriatric outpatients in hospitals for respiratory diseases. Beijing Children’s Hospital, for example, had seen 9000 patients per day, a third of them with respiratory problems.
Air pollution is a deadly problem. A study published last month by Peking University and environmental group Greenpeace estimated that there were 8,572 premature deaths in Shanghai, Guangzhou, Xi’an and Beijing in 2010 that could be linked to PM2.5 air pollution.
In the meantime, face masks are selling fast. The bestseller is the N95 mask, which claims to be able to block tiny PM2.5 particles. Not by choice, a mask has become the must-wear fashion item on the streets of many Chinese cities.

The skies over Beijing and northeastern China, on a relatively good day on January 3 this year (above), and on January 14 (below) when the air in Beijing was “hazardous”, but still less than half of the record high pollution of January 12. NASA
Click to enlarge

Tiny pollutants sparking national outrage

Particulate matter, or PM, is the term for particles found in the air, including dust, dirt, soot, smoke, and liquid droplets.
PM2.5 particles are about 1/30th the width of a human hair – making them small enough to invade even the narrowest airways. These are referred to as “fine” particles and are believed to pose the greatest health risks.
The PM2.5 level of pollution is held to be a more accurate reflection of air quality than other standards of measurement, but until relatively recently it was not made available to the public in China.
The term PM2.5 in now widely known among ordinary Chinese people, as debate has raged on the front pages of the nation’s newspapers. There have been strong calls even from state-controlled media for the government to publish truthful environmental data, and take stronger action to improve air quality and tackle environmental pollution.

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