• Sun
  • Sep 21, 2014
  • Updated: 10:32pm
NewsHong Kong

Worst smog of the year prompts Hong Kong government health warning

Low pressure system sends pollution levels rocketing across the city on the worst day of the year so far for air quality

PUBLISHED : Monday, 09 June, 2014, 3:03am
UPDATED : Sunday, 15 June, 2014, 3:11pm

Hong Kong choked on its smoggiest day of the year so far yesterday as a trough of low pressure left the city coping with pollution that represented a "serious risk" to health.

At 7pm and 8pm, all 12 of the city's general pollution monitoring stations and all three roadside stations recorded pollution levels posing a "very high" or "serious" risk to health. All but two general stations and all of the roadside stations were at level 10+, the highest level on the government's Air Quality Health Index (AQHI), introduced last year.

At 2pm, the Tung Chung general station recorded 24-hour concentration levels of PM2.5 - fine suspended particles small enough to lodge deeply into the lungs - at 128 micrograms per cubic metre, more than five times the maximum safe level set the by World Health Organisation. Ozone concentration hit 269, against a WHO maximum eight-hour mean level of 100.

Watch: How to deal with Hong Kong's smog

Ozone concentration was even higher elsewhere, hitting levels of more than 300 in areas including Central and Western, Tsuen Wan and Yuen Long, which all recorded 10+ AQHI readings.

An AQHI level of 10+ triggers a warning from the Environmental Protection Department for people with heart disease or respiratory illnesses to avoid outdoor activity, especially in areas with heavy traffic.

A department spokesman said the city was experiencing higher regional ozone pollution and that health risks were now high. Weak winds were not able to disperse pollutants, the spokesman added.

The deteriorating air quality came as a trough of low pressure affected southern China.

Professor Wang Tao, chair professor of atmospheric environment at Polytechnic University, said high levels of air pollution were typical during low-pressure systems.

"Weak horizontal winds and descending air create 'stable conditions', rendering pollutants in the city and nearby unable to move," he said. "People tend to pay more attention to PM, while the dangers of ozone pollution, which is actually getting worse, tend to go unnoticed."

Ozone is not emitted but produced through chemical reactions between nitrogen oxides from power plants and car emissions, and volatile organic compounds.

Most of Hong Kong's ozone pollution is a mix of background pollution from external and local sources. Long-term exposure to ozone is linked to asthma, bronchitis, heart attacks and even death.

Clean Air Network chief executive Kwong Sum-yin said days with multiple 10+ recordings occurred in January during a northeast monsoon, but yesterday would have marked the most polluted day so far this year.

The Observatory forecasts showers and squally thunderstorms today. Shortly after midnight this morning, the Environmental Protection Department's website was predicting "moderate to very high" health risks from pollution this morning, with a "low to moderate" risk in the afternoon.

Watch: The dangers of air pollution - videographic



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Impose huge road and import tax on cars over 2000 cc, make electricity cost much more progressively priced , increase airport tax for first class and business class travellers , get rid of this crazy idea of a 3rd runway , heavy fines for open burnings by those thug villagers , hotels, retail
Stores should pay an extra tax for the thousands of mainlanders who increase our carbon emission.
All worried about decline in retail sales, mtr, and arts
But when it comes to air and education, such a deafening silence - how shameful.
Do not overlook among the biggest polluter in HK - the Airlines!
The many hundreds of aircrafts and Airlines around the world taking of and landing here; thinking it's their god given right just because they pay landing fees.
Now the Government even wants to build a third runway.
The rich gov officials sent their family and children to America, Canada and Australia- leaving the rest of us here to choke on toxic air.
Dont forget those ugly and polluting container ships.
Survival of the richest....but perhaps not with poisonous air.
Agreed. I fail to see how having a busy airport can be seen as being good for HK when many of the incoming visitors just fly off elsewhere after touch-down and just leave the pollution behind.
Its mainland China's fault!!!!!!
"Watch: How to deal with Hong Kong's smog" That's what it says above the video and the implication is that we would find real solutions mentioned but no. The Clean Air Network does have excellent suggestions about what can be done about air pollution but that wasn't on the video. Edited out perhaps ?
I was born in HK... have lived here my whole life.... have 3 small kids. I love this place but days like yesterday really make me wonder if we should be packing up and moving on. the simple fact is that simply living in hong kong will shorten their lives. heartbreaking.
I Love HK, I would live here full time, but the Pollution, which most of comes from the Mainland, which continues with out restrictions, and Beijing wants HongKongers to love them! Never!
I'm in a similar situation. No kids yet but every day I cannot see them being raised here with super bad air roadside and a massive increase in cost of living (but not *quality* of living). Increased asthma risks aren't attractive either.
Comparable cities like San Francisco, Seattle, Toronto, Osaka are much more attractive with significantly lower air pollution.




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