Harder to breathe
Walking through the thick blanket of translucent smog that enveloped the jam-packed thoroughfares of Sham Shui Po, Ms Wong Siu-bing was suddenly seized by an uncontrolled spate of heart palpitations.
Perspiring profusely while desperately gasping for breath, she soon gathered her wits when the panting subsided and trudged on.
She is one of the tens of thousands of chronic asthma patients in Hong Kong, a pollution-stricken metropolis where respiratory diseases are one of the top leading causes of death, according to statistics from the Centre for Health Protection.
Having been diagnosed with asthma, she was subjected to multiple daily doses of inhaled steroids, while constantly experiencing sleepless nights marked by acute heart perspirations.
It does not help that her home is an 80-square-foot cubicle in a tenement building in Sham Shui Po, one of Hong Kong's most densely populated districts. It has only one window, which only opens onto horridly polluted roads.
Although Ms Wong's health has since improved having received subsidised medical treatment, the debilitating effects of asthma – most notably fatigue and lethargy – left her reeling from significant depression.
You leave me breathless
Clean Air Network, a local non-governmental organisation that campaigns against and educates the public about the city's air pollution, conducted a clean air search project on Sham Shui Po District between last October and January this year.
The project involved establishing 12 roadside air monitoring stations in six designated locations across Sham Shui Po. It found that the levels of fine suspended particulates, or PM2.5, recorded in all monitoring locations exceeded the World Health Organization's recommended standards by an average of 82 per cent.
PM2.5 are extremely fine particles measuring 2.5 micrometres or smaller in diameter. They have been proven to be more harmful than the larger PM10 particles as they can penetrate deeper into the lungs and thus obstruct oxygen absorption.
The project also found that the levels of PM2.5 particulates recorded in most of the monitoring locations are, on average, 65 per cent higher than simultaneous pollution readings collected at monitoring stations set up by the Environmental Protection Department.
But despite the discrepancy in PM2.5 readings collected by the CAN and the EPD in their respective monitoring stations (the CAN says the EPD's stations were set up too high above ground level), all the figures pointed to the fact that roadside pollution in Hong Kong has reached alarming levels.
The main culprit for Hong Kong's roadside pollution lies with the fleet of old diesel vehicles spewing black toxic fumes, which contain a deadly mix of respirable suspended particulates and nitrogen oxides, as they roam the city's roads surrounded by high-rise buildings.
In his book titled "Environmental Policy and Sustainable Development in China," Dr. Paul G. Harris, chair professor of Global and Environmental Studies at the Hong Kong Institute of Education, cites statistical data obtained from the EPD and Civic Exchange.
The research figures show that diesel commercial vehicles account for 88 per cent of respirable suspended particulates and nitrogen oxides emissions, while diesel buses make up about 40 per cent of all roadside pollution. The latter is supported by data collected from CAN's monitoring stations close to bus and/or minibus stops, which reveal that the concentrations of PM2.5 particulates are 40 per cent higher than the WHO recommended level compared to 33 per cent recorded at other stations.
Indeed, Hong Kong is trailing far behind many other developed cities in Western Europe and Asia, namely Singapore, in terms of air quality management. The 36,800 pre-Euro and Euro I diesel commercial vehicles still running on the city's roads attest to the laxity and obsolescence of its air quality regulatory system.
According to the WHO Air pollution ranking, Hong Kong's air quality is twice as worse than that of Singapore. Domestically, the picture looks even grimmer for Hong Kong as it is the second worst city (after Urumqi, the capital of Xinjiang) in China for nitrogen dioxide, which comes primarily from vehicle exhaust.
The European emissions standards for light and heavy duty commercial vehicles, which are enforced in all EU member states and widely used as a global benchmark for vehicle exhaust emissions around the world, are applied under a system of classification based on the fuel efficiency of the vehicle, with Euro I being the least efficient and Euro V the most efficient.
According to the EPD, the 117,000 diesel commercial vehicles licensed in Hong Kong in 2009 comprised 23,800 pre-Euro (purchased prior to the introduction of emissions standards in 1992); 15,100 Euro I; 28,000 Euro II; 31,000 Euro III; 20,000 Euro IV, and only 150 Euro V.
While pre-Euro vehicles account for only 20 per cent of road traffic in Hong Kong, they generate 34 times more respirable suspended particulates and 2.6 times more nitrogen oxides than Euro IV ones. Additionally, a Euro III vehicle emits five times more RSPs (PM10) than and 1.4 times as much nitrogen oxides as a Euro IV.
Combined, Pre-Euro, Euro I and Euro II account for 57 per cent of the total number of diesel vehicles on the road, producing 73 per cent of total roadside respirable suspended particulates (PM10) and 34 per cent of total roadside nitrogen oxides.
The dingy pearl of the Orient
Despite the fact that more than 50 per cent of Hong Kong's air pollution comes from the roadside, oceangoing vessels and factories from the Pearl River Delta have their equal share of the blame.
Hong Kong is arguably one of Asia's most vibrant shipping hubs, and yet large oceangoing vessels sailing past or berthed at the city's cruise terminals produce more respirable suspended particulates, nitrogen oxides and sulphur dioxide than power plants.
Mr Patrick Fung, campaign manager of Clean Air Network, pointed out that the Hong Kong government had long been reluctant to commit themselves to long-term emissions standards, and had never aimed to reach beyond the interim pollution targets.
The growing pervasiveness and severity of Hong Kong's pollution have finally prompted the government to come up with more stringent, sweeping measures to clean up the air, with Chief Executive Mr Leung Chun-ying proposing that a $10-billion subsidy scheme be set up to replace more than 80,000 pre-Euro and Euro I to III diesel vehicles on the city's roads.
In addition to the proposed subsidy scheme to phase out heavily polluting diesel vehicles, Mr Leung has suggested bringing in more radical measures to curb air pollution from shipping by stalling on-shore power supply facilities, so as to encourage oceangoing vessels to switch to electric power while berthing.
That said, the city's Air Pollution Index, which measures the air pollution levels in Hong Kong, is "outdated" as its values fail to reflect the seriousness of existing pollution, not to mention informing the general public how dreadful the air it is they are inhaling during normal days.
The API is based on the Air Quality Objectives introduced by World Health Organization in 1987. It converts air pollution data from several types of pollutants, namely sulphur dioxide, nitrogen oxides and carbon monoxide, into a value ranging from 0 to 500.
The forecasting system is adopted to
alert the public, especially susceptible groups like those with heart or respiratory illnesses to elude the onset of serious air pollution episodes. Nevertheless, it has not been updated since it was adopted 25 years ago.
Adding to the list is the existing mechanism that measures only PM10, the relatively large particles, excluding the finer PM2.5, which poses the greatest health risk because it can lodge deeply into the lungs.
"The government wants measures that are easily (usually already) achieved. Naturally, its key stakeholders, namely business interests, also like this. The public suffers, of course," said Dr. Harris at the Hong Kong Institute of Education.
Environmental experts believe a binding agreement with the Guangdong authorities aimed at tackling pollution from the sea and from factories across the border is surely possible in the long term, are afraid it is merely a "red herring".
"The government could acquire this right now," said Dr. Harris. "Again, it is its vested interests, warped perceptions of the importance of transshipment for the economy, and an enormous discounting of human health that stops the government from doing it. Essentially blaming Guangdong or the delta traffic issue is a way for the government to divert attention. It's shameful!"
The "fragrant harbour"
The worsening air quality has raised concern that Hong Kong, home to thousands of expatriates, is no longer desirable place to live. A survey done by office space provider Regus, of some 200 international and local companies, suggests that three out of four companies said the city's poor air quality made it harder for them to attract and retain overseas employees.
Another survey, done by the American Chamber of Commerce, has found that almost half of its members knew of professionals who left the city because of the escalating pollution.
"Right after my child was born, my husband and I had no choice but to move out of this city which we've always been in love with," Mrs Kate Anderson said, citing her concern for her child's health. She still calls Hong Kong her "all-time favourite".
Reported By Brian Yap, Ruby Leung, Venus Ho
Edited by Kristine Basilio, Roy Chan, Kris Lui
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