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The Causes Behind Hong Kong’s Air Pollution Problem

On August 1, the Air Pollution Index readings in Hong Kong hit an all-time high, with all three of the city’s roadside air-monitoring stations (located in Mong Kok, Central and Causeway Bay) logging worryingly elevated ratings. In fact, the only other instance readings were this high was when a sandstorm from China blew dust all over the city in 2010. This time, Hongkongers singled out Typhoon Vicente as the culprit: after the T10-level storm passed over us on July 24, it caused a meteorological effect that made it more difficult for pollutants to disperse. Facebook and Twitter feeds exploded with photos and complaints about the noxious environment, which made even inhaling an uncomfortable chore. (When we put out a call for photos to our readers, pictured in this article, we were inundated with shots within moments.) But is the storm really to blame, or is it just an easy scapegoat for a difficult problem? HK Magazine decided to take a closer look at what—or who—is really behind Hong Kong’s awful air pollution, from mainland China’s factories to Hong Kong’s own lax government policies to energy-wasting Hongkongers themselves.

Aug 16, 2012


We love to complain about the mainland’s toxic factories, but how much can we really blame China for our noxious air?

Hongkongers seem especially fond of chalking up our abhorrent air quality to the folks across the border. With hundereds of factories belching out emissions in neighboring Guangdong province, this assumption seems to make sense. Besides, mainland China’s no angel when it comes to air pollution—Beijing, for instance, is bemoaned by tourists and residents alike for its blanket of chronic brown smog. Melonie Chau of local green charitable organization Friends of the Earth concedes that there may be some grains of truth to this much-trumpeted accusation—regional conditions do indeed contribute to Hong Kong’s poor air quality to a certain extent. “The particulate matter emissions of Hong Kong and the Pearl River Delta region are in the proportion of one to 99,” she says. “Hong Kong can do very little to change it.” However, she goes on to add that the impact of local roadside emissions on Hong Kong’s air is much greater than whatever the mainland dishes out to us day after day.

In fact, a deeper look reveals that, comparatively, the mainland contributes less to local pollution than Hongkongers themselves: a research study conducted by the Hong Kong University of Science and Technology in 2007 indicates that regional sources contribute to 36 percent of Hong Kong’s overall air pollution, while local sources are responsible for a whopping 53 percent of the total. A study conducted by Hong Kong’s Environmental Protection Department and the Guangdong Province Environmental Protection Bureau in 2002—that there isn’t a more up-to-date report should speak for itself—echoes the fact that, while factories and power stations in the Pearl River Delta region do add to the poor air quality in the city, local traffic is actually the biggest contributor. One more thing to consider: we give just as much as we get. Hong Kong pollutants spread across the border as well, worsening the air outside of the city.

Our government is also doing less to combat pollution compared with our mainland counterparts. Mike Kilburn, head of environmental strategy at non-profit think-tank Civic Exchange, lays out the contrast: “Hong Kong used to be the environmental leader in China, and [it] has now become a follower—China introduced its new air quality standards before Hong Kong in January this year. This is a disgrace. We are the richest city in China and have the most experience in environmental management and therefore [we have] the ability to set the standard.” Erica Chan, campaign manager at local NGO the Clean Air Network (CAN), assesses Hong Kong’s efforts to clamp down on air pollution in light of those put forth by the hazy Chinese capital. “Beijing suffers far higher levels of air pollution than Hong Kong does. However, their government is much more aggressive in tackling the problem,” Chan says.

“In 2011, the Beijing government set aside $2.1 billion [HKD] to improve air quality, $390 million of which was for vehicle emissions control. In comparison, the Hong Kong government allotted only $559 million for air quality measures.” Other major cities—including Shanghai, Guangzhou and Shenzhen—are also taking big steps to curb air pollution—Shenzhen aims to replace 50 percent of its combustion engine buses with electric buses or hybrids by 2015, while Hong Kong again comes up short, with no concrete plan to transition its fleet of buses from gas to electric. Government representatives in Guangdong are also cooperating with the local government to reduce air pollution within the region.

Verdict: Blaming the mainland for our bad air isn’t only counterproductive—it’s more or less false.

Hong Kong on a clear day vs. a polluted one | Photo credit: Megan Jack

The government

Our government could certainly be doing more to improve our air quality.

Government policies are the key to reducing air pollution in any built-up city. But with toothless initiatives, an unclear direction and a lack of targets, is Hong Kong’s government responsible for our hazy atmosphere? While individuals can do their part to help out, experts agree that at the end of the day, wide-ranging, systematic change implemented by—oh yes—the government would do the most good. “Individual behavior can change the air quality by very little,” says Chau of Friends of the Earth. “Government policy is much more important.” Although, Chau adds, “I can suggest [that individuals use] more public transportation and turn off idling engines.”

Diesel commercial vehicles—such as buses and taxis—account for a major proportion of pollutants in the air. To delve into the nitty-gritty: according to a paper published by Civic Exchange in 2010, motor vehicles are responsible for 30 percent of total respirable (as in, able to be breathed in) suspended particles (RSP) and 22 percent of nitrogen oxide emissions in the air. Then, out of these percentages, diesel commercial vehicles account for 88 percent of vehicular emissions of RSP and 76 percent of nitrogen oxide emissions. These staggering totals are partially due to the fact that most buses careening about the streets are inefficient and outdated.

The Environmental Protection Department (EPD) uses the European Union’s various emissions standards (ranging from before there were standards to level III, with a higher number meaning stricter caps and lower emissions) to rank our buses. According to the EPD, there were 372 pre-Euro, 1,335 Euro I, 2,673 Euro II and 1,257 Euro III buses operating in our city at the start of 2010. Right now, the EU’s vehicles are conforming to Euro V—the most stringent level, the one that cracks down on emissions the most. In this light, we are far, far behind. To deal with the problem, the EPD ran a one-off scheme from 2007 to 2010 under which they subsidized owners of gas-guzzling vehicles who wanted to replace them with more environmentally friendly models. Only a quarter of the vehicles were replaced as a result. The government’s initiative, some say, wasn’t enough. “The subsidy amount was too low,” comments Chan of the Clean Air Network. “It couldn’t even compensate for the rising cost of buying a new vehicle.”

So while the government is taking steps to combat air pollution, its efforts have been criticized by environmental NGOs as doing too little too slowly. “To mitigate the roadside air pollution, the Hong Kong government has done very little and has no clear focus,” says Chau of Friends of the Earth. “The government has no timetable for when these [old] vehicles will be pulled [off the roads] or retrofitted. Green groups also suggest setting low emission zones and cutting bus routes, but all [these plans] were rejected.” Another example of how Hong Kong is lagging behind? The EPD plans to set aside money in 2013 for bus companies to purchase 36 electric buses for a trial run. Meanwhile—as mentioned earlier—Shenzhen is already halfway through replacing all of its emissions-spewing buses with electric or hybrid vehicles.

Besides the problem of traffic, the other hot topic in governmental environmental policy is Hong Kong’s Air Quality Objectives (AQOs), which are used as a benchmark for how low the concentration of various pollutants in the air should be. It also informs the Air Pollution Index (API): air quality is measured at various locations and each pollutant from the reading is compared to its corresponding AQO in order to produce an index value. The AQOs were set up in 1987, based on the World Health Organization’s air pollution guidelines at the time. While the WHO’s standards have since been updated and improved, Hong Kong’s AQOs haven’t moved an inch. “The government has finally promised to update it this year,” says Chau. “However, it will be implemented as soon as 2014. That means the public has to bear the poor air quality for two more years.” Hong Kong’s air quality standards were put up for review in 2009, when the government only decided to meet the WHO’s current guidelines where it was convenient; for instance, with nitrogen dioxide and carbon monoxide. Elsewhere, the government chose to base their objectives on the WHO’s entry-level standards which were meant as a starting point for countries with high pollution, with the idea that pollution would gradually be reduced and WHO’s long-term guidelines would then be adapted instead. “In order to retain any credibility, the government must set a timeline for implementation of the WHO air quality guidelines,” says Kilburn of Civic Exchange. “Right now, we don’t have one.”

Why is this set of standards such a big deal? Not only do they help measure just how cruddy our air quality is—and provide objective, unbiased statistics to the Hong Kong public and the international community—but they could potentially serve as a way to ensure that power plants, vehicles and other sources of pollution keep their emissions under control. Professor Anthony J. Hedley, former Professor of Community Medicine at Hong Kong University and an outspoken air pollution researcher and activist—who went so far as to relocate from Hong Kong to the Isle of Man two years ago because the pollution was so bad—states that “the guidelines need to be used for environmental, political and economic interventions, to ensure that the [existing] levels are brought down to well below those guidelines.” But with the AQOs as lax as they currently are, it hardly matters if Hong Kong follows them or not.

“This is an issue of vital importance,” concludes Professor Hedley. “And Hong Kong is so seriously adrift now in terms of its air quality management, that even with the best will in the world, it’s going to take a long time before we turn this around.”


People were saying that last fornight’s storms were contributing to the toxic fug. What the hell?

The pollution over the last few weeks has been the worst since at least 2010. And everyone—from big news outlets to the peanut gallery on Facebook—has been commenting about the smoggy haze left over in the wake of Typhoon Vicente last month, which prompts us to wonder just how, exactly, the storm exacerbated our bad air quality. It turns out that, while Vicente may have been the biggest typhoon since 1999, it isn’t the biggest cause of Hong Kong’s air pollution. In fact, it technically isn’t a cause at all.

Yes, the typhoon may have pushed air pollution to a record high. (Similarly high air pollution readings followed 1999’s Typhoon York.) An expert on atmospheric shifts, Professor Alexis Lau of the University of Science and Technology explains that air pressure changes caused by the typhoon can make the surrounding air more stagnant, making it harder for pollutants to disperse, and easier for us to see. But he goes on to state that typhoons wouldn’t have such a negative after-effect on Hong Kong if the city’s all-the-time pollution was less severe overall. “If we didn’t have the emissions [in the first place], we wouldn’t see the bad air quality when the typhoon is around,” says Professor Lau. He admits that the typhoon is, indeed, responsible for worsened air pollution on a day-to-day basis, but advises that HongKongers look to broader readings—such as annual means over the last 10 or 20 years—instead of daily readings, in order to glean a more accurate picture of changes in air pollution.

Our other air pollution experts agree. “The weather conditions only exacerbate the situation, and are not the source of the high concentrations of pollutants,” says the Clean Air Network’s Chan. Professor Hedley sums up the situation succinctly: “The typhoon demonstrates that the whole area is very badly polluted. It simply underscores what we already know.”


The high-sulfur fuels used by the shipping industry are choking the communities near our container ports.

Most of us may be aware of the negative effects of traffic on air pollution—we constantly have to deal with cars and avoid nearly being run over, after all—but an often-overlooked cause of the city’s bad air is the thousands of ships that pass through our harbors every day. According to a report from Civic Exchange, out of the 325 “bad air days” (as measured by local authorities) we have a year, 120 days—or 37 percent—are mainly caused by ships as well as local vehicles emitting sulfur dioxide. The report also indicates that air pollution readings are consistently higher in districts where there are container terminals, such as Kwai Chung. This is mostly due to the fact that these ships are powered by bunker fuel, and that Hong Kong allows ships to use fuel of up to 3.5 per cent sulphur, so it releases a high amount of sulfur dioxide when it is burned.

By contrast, our everyday ferries and small recreational boats use fuel containing just 0.5 percent sulfur, and they’re being pressured by the government to switch to fuel with even lower sulfur content. Clearly, then, it’s the mammoth vessels carting goods to and from Hong Kong and China that are the problem. The Marine Department also imposes a penalty of $10,000 on ships whose smoke is “in such quantity as to be a nuisance” or “affect[s] the safety of life,” but there were only eight such prosecutions between 2005 to 2007, and a mere five more since 2008. Additionally, ships usually aren’t investigated or fined unless someone calls in to report them first—meaning that ordinary citizens are being relied upon to be watchdogs, even though they are very unlikely to take that role seriously and act on noxious smoke-spewing ships they see. The Marine Department is taking some action of its own, thank goodness, setting up its own monitoring operations in harbors in 2011. While the department says it has issued warning letters, it remains unclear how much its measures actually address the problem and work to keep our water (and air) clear of polluting ships.

Urban Planning

Everyone knows about the “wall effect,” but can we really blame our high-rises for our bad air?

Hongkongers are constantly complaining about high-rises destroying the quaint qualities of their neighborhoods, but the closely packed buildings are responsible for more than just that. Tall buildings that are tightly packed together can create a “street canyon” effect on air pollution—which means that as Hong Kong and the Pearl River Delta region release pollutants into the air, our skyscrapers then trap them and make it more difficult for them to disperse. Nice.

As with typhoons, though, tall buildings exacerbate pollution, but don’t directly cause it. Unfortunately, there’s also little that can be done about the phenomenon once the buildings have already been built. There’s still hope for the future, as long as Hong Kong’s urban planners actively avoid constructing dense clusters of high-rises down the line. “The government should think of the air pollution issue during the initial stage of urban planning,” says Chan from the Clean Air Network. “Open space should always be taken into account.”

Hongkongers Themselves

What can we do to make our city a less toxic place to live?

Admittedly, while the bulk of our air problems appear to stem from regional air quality as well as the lax policies of our government, Hongkongers aren’t totally in the clear, either. According to environmental charity organization Clear the Air, 57 tons of respirable suspended particles and 295 tons of carbon monoxide are released into the air every year by smokers, while idling a vehicle for 10 minutes everyday results in the additional consumption of 100 liters of petrol after just one year. The broader picture—and an honest-to-goodness solution—might be out of our hands, but we can at least help reduce Hong Kong’s air pollution in smaller ways.

“Local people feel helpless in face of severe air pollution, but they can [actually] make a difference by changing their behavior,” Chan of the Clean Air Network states. “For example, by switching off idling engines or reducing electricity wastage.” Hongkongers can also get more involved by being grassroots activists, or watchdogs of sorts—write letters to political bodies, or report idling engines or smoky shipping vessels to the proper authorities.


What’s Your Take?


Brian Hung, 29
Tour guide

I think the biggest reason for Hong Kong’s air pollution is the traffic. And also buildings in Hong Kong are too tightly packed—the polluted air cannot disperse. Additionally, the pollutants from factories in the Guangdong area worsen the problem. The whole of Hong Kong this week has been gray and opaque.

Dany Gauthier, 31
Quality Inspector

It’s pretty much the same as Shanghai, Beijing, Tokyo. I’ve seen worse [than Hong Kong], but I’ve seen better. But I would say the big difference with Hong Kong, compared to other cities, would be the amount of traffic. Some cities, like Tokyo, have better public transport, like trains and subways, so there are fewer cars on the road. And I don’t know, outside of Hong Kong, how many factories there are in the region, and they might not have the best environmental laws.

Lai Hon-wing, 80

Cars produce a lot of pollutants; air conditioning as well. The problem is inevitable as long as there are so many people in Hong Kong. When I was young, there were fewer buildings around, more open space. But now, because the land is so expensive, developers keep building really tall buildings, so the bad air is trapped in the city.

Ada Lam, 30

I think the main problem is trash. Hong Kong creates a lot of trash because of the large population. You can find trash in every corner of Hong Kong. I think cars, factories, people exist in every place, but I think for Hong Kong the biggest problem is trash. We should try to be more environmentally friendly.

Natalie Chan, 21

I think the biggest cause of air pollution in Hong Kong is the pollution in China, the vast number of factories and the polluted substances they dispense. Hong Kong also has a lot of traffic and the buildings in Hong Kong are built very close to each other. The air cycling system is not as good. I think this also plays a major part in causing more serious pollution.

Taylor Ma, 26
Make-up Artist

I think a lot of things together cause Hong Kong’s serious pollution. There is always a lot of construction going on, which creates a lot of waste. I think the process of handling waste will cause pollution as well. The bad air pollution affects people’s health, as well as their skin. And because I work with make-up, I feel very strongly that air pollution directly affects the condition of people’s skin.

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