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Gray Skies Ahead
by Stan Sesser, staff reporter of the Wall Street Journal

HONG KONG -- When Simon S.C. Chau walks down a busy street in Hong Kong, picking him out from the crowd is easy -- he's the one wearing a gas mask. When he teaches his classes in English translation at Hong Kong Baptist University, he carries with him a large air purifier to plug in. And at his home in Tai Po, one of the most pristine areas of Hong Kong, he surrounds himself with plants and forgoes all carpets, which can emit unhealthy fumes.

"People stare at me and think I'm mad for using a gas mask," says 57-year-old Mr. Chau. As he places a soiled gray filter for his gas mask alongside the pure white one he's currently using, he notes that "in just three weeks it turned gray. You can imagine what happens to your lungs. When people say I'm mad, I show them these two versions."

Air pollution, which Prof. Chau says has traditionally been "number 95 on the list of concerns" of Hong Kong's Chinese population, is finally getting some attention from residents. After battling record pollution levels and seeing their favorite views obscured by constant smog, locals are increasingly concerned about what bad air is doing to their health. Moreover, the failure of the Hong Kong government to cut air pollution after more than a decade of trying serves as a warning signal to the rest of Asia, where a soaring number of vehicles on the road and growing industrialization threaten unprecedented air-pollution problems.

The World Health Organization calculates that air pollution contributes to 800,000 deaths in the world each year -- and two-thirds of these are in Asia. In the region's biggest cities, residents are being assailed by a dangerous cocktail of pollutants that spew from vehicles, power plants and industrial smokestacks. Emissions such as nitrogen oxides, sulfur dioxide, carbon monoxide and particulate matter can cause heart disease and exacerbate asthma and upper respiratory infections and, in some cases, spell the difference between life and death.

Despite major efforts by Hong Kong authorities to clear the air, such as replacing the fleet of diesel taxis over the past four years with vehicles powered by cleaner liquid petroleum gas, the situation is getting worse. The city's air pollution index -- a government measurement that records pollutant levels in 14 key areas of Hong Kong -- topped 200 in September for the first time in history, a level that is termed "severe." An almost constant pall of smog and haze -- coming mainly from factories and power plants in nearby Guangdong Province, many of them owned by Hong Kongers who set up shop in China to take advantage of low wages and lax pollution laws -- obscures the famous view from Victoria Peak across the harbor to Kowloon. Choking diesel fumes from buses and trucks permeate the major roads. So far this year, through Nov. 9, Hong Kong has had 79 days where the air pollution index has exceeded 100 ("very high") for at least one monitoring station, compared with just 53 days for all of 2003.

Yet by Asian standards, Hong Kong is far from the continent's most polluted city. According to a joint World Bank-Asian Development Bank study of air pollution for 20 major Asian cities between 2000 and 2003, the level of suspended particulate matter in the air, which many researchers now consider the most dangerous pollutant, significantly exceeds Hong Kong's in nine cities. For the most hazardous of these particles -- those under 10 microns in diameter, which can penetrate even a face mask -- Beijing and New Delhi have more than three times Hong Kong's level. In many of these cities, rapid industrial growth in the absence of pollution controls, an increasing use of coal to meet growing energy needs, plus a burgeoning middle class that is adding thousands of cars to the road each month, is providing the recipe for a witch's brew of air pollution.

Of the 20 cities, only Singapore's air falls within the safety limits for each of the major pollutants. Singapore not only has strict pollution controls, but restricts the number of cars on the road by auctioning the rights to own a vehicle -- a formula that no other Asian country has yet dared to adopt. Cities such as Manila, Bangkok and Seoul have already paid a big price for vehicle pollution. Now they're being joined by major cities in China, already heavily polluted from industry: Car sales in China last year more than doubled to two million from the year before, and are projected to grow much further.

The situation across Asia could get much worse even if strict new measures are implemented, says Cornelius Huizenga, head of the secretariat of the Clean Air Initiative for Asian Cities, a joint program of the World Bank and the Asian Development Bank. Mr. Huizenga points out that the increase in the number of vehicles on the roads, together with the growth of industry and energy consumption, threatens to outweigh any progress made with pollution control.

That has clearly been the case in Hong Kong. The government expects significantly cleaner air by 2010 as a result of an agreement reached two years ago with neighboring Guangdong Province to sharply reduce industrial emissions; Hong Kong authorities blame China for 80% of the city's air pollution. But, concedes Tse Chin-wan, Hong Kong's principal assistant secretary for the environment, for at least the next two years, while China ramps up its program to control emissions, "it's likely our pollution will deteriorate before we see improvement."
Families Fleeing

Andrew Pearson, for one, is not going to wait. Just last week, the 39-year-old information technology specialist for the University of Hong Kong gave up his job and moved with his wife and three-year-old daughter to Sydney. After 16 years in Hong Kong, air pollution was "definitely the deciding factor" for the move, the British-born Mr. Pearson says. "My daughter and I have been taking nasal sprays and various antihistamines for coughing and rhinitis (an inflammation of the mucous membrane of the nose)," he adds. "We're constantly coughing, but when we go away it's fine. Our doctor has repeatedly told us these are pollution-induced."

The move "is a hard thing to do," he acknowledges, noting that he'll be making a big financial sacrifice. "Life in Hong Kong is nice, but we don't see how we can stay." He says he's not the first person in his department at the University of Hong Kong to leave because of pollution. "Two friends went back to Scotland and one moved to Singapore," he states. "They all had small children."

Ben Tyrrell, the head of Relocasia, a Hong Kong moving company, says that Mr. Pearson and his university colleagues are far from alone. "We're starting to see the environment steadily creeping up in the level of priorities for leaving Hong Kong, especially for young families," he states. "There's not a panic, but we get a lot of corporate business and that factor is being discussed more. We're finding the environmental factors are leading people to look toward Singapore."

People like Mr. Pearson are beginning to worry Hong Kong authorities, who fear that increasing publicity about the city's reputation for dirty air could stifle economic growth and tourism. Before my interview with Mr. Tse, the environmental official, even began, he pulled out a chart showing that from 1978 through 1980, Los Angeles had an average of 113 days a year when its Air Pollution Index topped 200, compared with Hong Kong's one day this September. "Our reading of 201 was at one monitoring station for one hour," he says. "But the media is pegging it as the record high in the world." Mr. Tse vows that "we're very determined to tackle the air pollution problem."

Still, Hong Kong officials, like those throughout Asia excepting Singapore, haven't escaped criticism for their reluctance to restrict traffic and to stand up to big corporate polluters. Take, for instance, Hong Kong's largest electricity provider, and consequently one of its biggest polluters, CLP Power, a unit of CLP Holdings Ltd. The bulk of its power production comes from two Hong Kong generating plants, one fueled by natural gas and the other by a combination of natural gas and coal. Last year, CLP said it had recalculated its gas reserves, located near China's Hainan Island, and found them smaller than originally estimated. To stretch out the natural gas supply, CLP substituted coal for a large part of the natural gas at its second plant, Castle Peak, near Hong Kong's airport.

The result: according to figures supplied by CLP, 2003 emissions of sulfur dioxide from CLP's two Hong Kong plants soared 90% from 2002, while nitrogen oxides rose 63% and particulates 42%. The CLP spokeswoman says that a 2002 report by the Hong Kong and Chinese governments (based on 1997 figures), found that CLP's plants accounted for 5% of the sulfur dioxide in Hong Kong's air, 4% of the nitrogen oxides, and 0.4% of particulates.

Why didn't the government insist that CLP simply find other sources of natural gas, since the Hainan field would still be several years away from depletion at the old usage rate? "I don't want to speculate in public," Mr. Tse responds. "We're still negotiating with them." A CLP spokeswoman says that "we are actively exploring the finding of successor gas."

Unnecessary Deaths
As air pollution increases, so does research on its health effects, and the results are not encouraging. "Definitely, many people are dying unnecessarily, related to both traffic pollution and conventional pollution," says Dr. Gary Wong, a specialist in respiratory diseases, who is a professor at the Chinese University of Hong Kong's School of Public Health. "Everyone in mainland China, when they accumulate enough money, will buy a car," he adds. "They need to know the price they will eventually pay."

A laundry list of air pollution's health effects is stunning. "It is mainly a health problem that translates through to huge economic and social costs," says Charles Melhuish, who until this year ran the Asian Development Bank's Clean Air Initiative. According to Dr. Wong Tze-Wai, a professor of community and family medicine at the Chinese University of Hong Kong, for every 10 micrograms per cubic meter that particulates in the air increase -- a figure that represents only a relatively small jump in air pollution -- Hong Kong experiences an increase of 0.5% to 1% in the number of deaths.

"The relative risk is small," he says, "but applied to the whole population this becomes a big problem because the exposure is universal." He points out that "in Hong Kong we average 100,000 hospitalizations due to respiratory illness each year and 150,000 due to heart disease. So even a small percentage (jump in the death rate) will result in a big increase in deaths. You're talking about thousands of cases."

Air pollution doesn't actually cause asthma -- children in polluted cities in China and Indonesia, for instance, have much lower asthma rates than in pristine countries such as New Zealand. (One theory holds that exposing children to the bacterial and viral contaminants of a less healthy environment strengthens their immune systems.) Nor does air pollution cause pneumonia and some other serious upper respiratory diseases; although it can make you more susceptible to these infections, viruses and bacteria are the actual villains.

But once you've contracted asthma, bronchitis, emphysema and other upper respiratory diseases, air pollution can push you over the line between survival and death. It compromises lung function, the ability to breathe in and out. "When pollution levels rise, you see a rise in hospitalizations," says Dr. Gary Wong. "If you have a patient with pneumonia, they have a higher chance of dying if that patient was raised in a highly polluted area. Any infection of the lung like pneumonia would be more likely to lead to respiratory failure; you can't breathe enough air and you die."

Heart Attacks
Exhaust fumes alone cause multiple problems. Diesel exhaust is a probable carcinogen. When carbon monoxide, which is emitted from motor vehicles, is inhaled, it replaces oxygen in the bloodstream, interfering with the normal transport of oxygen to the heart and brain. Although air pollution is most generally linked to respiratory problems, new research is finding that it can also contribute to heart attacks.

Just last month, a study in the New England Journal of Medicine reported that sitting in traffic nearly triples the risk of suffering a heart attack a short time later. While the stress of waiting in traffic can contribute to the problem, researchers found that the fine particles emitted by vehicles can cause fatty plaques in arteries to rupture, causing a heart attack.

Researchers are also increasingly linking air pollution to early-stage cardiovascular problems, just as with smoking. Earlier this month, a University of Southern California researcher told an American Heart Association meeting that a study he conducted in Los Angeles suggests that tiny particles of air pollution trigger artery damage that can eventually lead to heart attacks.

If all this isn't enough bad news, a polluted environment might even negate the effects of exercise, according to a Hong Kong study. Dr. Wong Tze-Wai studied children between the ages of 8 and 12 in a relatively clean part of the New Territories and in a polluted area of Kowloon. "Normally," he said in an interview, "exercise increase your fitness and cardio-pulmonary functions. In the cleaner district, the more they exercised, the more fit they were." But in Kowloon, he notes, "the beneficial effect was not there. The theoretical beneficial effect of exercise was cancelled out by air pollution, and we don't know why." Dr. Wong adds that "it might affect adults also, but we don't know."

Such warnings weigh heavily on some Hong Kongers who worry about air pollution but see no way out. For Prof. Chau, the teacher of English translation courses, a gas mask is an extreme but effective solution.

Prof. Chau hasn't had serious respiratory problems. Instead, he was motivated to don the mask by a friend's example rather than by illness. "He was so convinced that our health is threatened by air pollution that he argued any sane person in Hong Kong should be doing this," he says. "I didn't need a lot of convincing."

Air pollution is such an object of concern these days that Prof. Chau's gas mask has been drawing as much interest as derision and stares. "I've been wearing the mask for three years, and now I have colleagues doing the same thing," he says. "I'm stopped time and again by people on the street who ask where they can get one."

Write to Stan Sesser at [email protected]


Major air pollutants and their potential impact on your health.



Major Sources

Health Effects

Particulate matter less
than 10 microns in diameter (PM(10)

The tiny particles in the air that can penetrate a surgical mask and be deeply inhaled.

Auto exhaust,particularly diesel; stationary sources such as power plants burning coal.

Aggravation of respiratory and cardiovascular diseases that can lead to premature death; changes in lung function.

Nitrogen dioxide (NO2)

A gas that can be a component of photochemical smog, producing its yellowish-brown color.

Vehicle emissions; power plants.

Increased airway resistance in asthmatics; decreased lung function; increased susceptibility to respiratory infections.

Sulfurdioxide (SO2)

A colorless gas with a sharp, irritating odor.

The burning of coal by power plants and other heavy industry.

Reduced lung function; wheezing; chest tightness and shortness of breath.

Carbon monoxide (CO)

A colorless, odorless gas.

Gasoline-burning vehicles.

Hinders transport of oxygen from blood to tissues. At risk: fetuses and people afflicted with heart disease.


A colorless gas with a distinctive odor formed by reaction of volatile organic compounds with sunlight.

Volatile compounds come mainly from vehicles with poor combustion, such as two-stroke engines.

Chest pain; coughing; shortness of breath; aggravation of asthma.

Source: Clean Air Initiative for Asian Cities.

Note: Pollutants are components of the Air Pollution Index, developed by the U.S. Environmental Protection Agency and used in many major cities, including Hong Kong and Bangkok, to track air pollution at monitoring stations.

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