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Clean Up Hong Kong Air Pollution

The right route


SCMP Dec 20, 2007

To clean up air pollution, should we be doing more of the same – that is, taking an incremental approach – or making a change in direction? Going down the same path but doing more is fine if the course is right. After all, we cannot do everything in one fell swoop. But if the steering is off, then a directional adjustment is needed.

According to results of a survey released on Monday, the majority of 81,000 Hong Kong respondents would be willing to pay more for transport in return for cleaner air. This should surprise no one; poor air quality has bothered Hongkongers for many years.

The issue is: which things does the government want people to pay more for? Let’s take roadside air pollution as a point of discussion. It is not only appallingly high, but has become almost a normal condition. If the public paid more for public transport, would that improve roadside air quality?

Would higher transport costs go towards subsidies to build more rail lines? Or to encourage operators of buses and light buses to replace old vehicles earlier with less-polluting models? How would commercial trucks be dealt with, since they spew out the highest amount of polluting emissions?

Taxis and many light buses have already converted to LPG; new vehicles must have Euro-IV-standard engines; and only ultra-low-sulfur diesel is available. But those measures have not been nearly enough to clean up roadside air pollution. Thus, doing more of the same – pushing new vehicles to have Euro-V-standard engines, and using even cleaner fuels when they become available – will not make much difference if Hong Kong’s old vehicles are not replaced.

How can we make owners replace their vehicles? The government has already announced a public subsidy scheme – the “carrot”. But there’s no “stick” unless owners are given a deadline, in the near future, for replacing the most polluting vehicles.

London faced a similar challenge. Its solution is to turn the whole of Greater London into a low-emission zone and is starting a phased-in scheme from next February, pushing commercial vehicle operators to upgrade their vehicles. It uses its existing electronic road pricing system to track vehicles going into the city; those with old, polluting engines must pay a penalty every time they cross the city boundary. So, if you are running a trucking business and you have to go to London frequently, the penalty becomes an expensive operating cost; you had better buy a new lorry. The authorities also offer a replacement subsidy scheme, so the stick and carrot work together.

Launching the electronic road pricing system was a change of direction for London, and would be for Hong Kong as well. But our government has not yet been able to adopt it, although the scheme was first raised in the 1980s.

Many of Hong Kong’s roads are narrow, with high vehicle density, creating our infamous “street canyon” effect that traps vehicular pollution. That in turn contributes to the extremely poor roadside air quality. With so many people affected on a daily basis, it is shocking that much more has not been done already to protect public health. Just think of how many people live and work right next to, or near, heavily used roads – and how many schools, hospitals, clinics and elderly homes are affected. It’s a pity we don’t have a surgeon general to champion public health; there are plenty of voices arguing for commercial interests.

The government’s recent interest in building more rail lines makes sense. But it must also make clear that it will reduce road building and use demand-side mechanisms like road pricing to deal with congestion. It should use town planning to ease the street canyon effect and tighten air quality objectives, in addition to taking old, polluting engines off the road.

Unless there is a clear policy to change direction, incremental measures, including banning idling engines, will not make enough of a difference.

Christine Loh Kung-wai is chief executive of the think-tank Civic Exchange

Diesel Air Pollution Linked To Heart Attack And Stroke

Diesel Air Pollution Linked To Heart Attack And Stroke In Healthy Men

UK and Swedish researchers found that diesel fumes from road vehicles increased blood clots and platelets in healthy volunteers. These are symptoms closely linked to increased risk of heart attack and stroke.

The researchers reported the results of a small study to a meeting of the American Heart Association’s Scientific Sessions 2007 held in Orlando, Florida, earlier this week.

Previous observational and epidemiological studies have also shown a close link between exposure to traffic pollution and heart attack, said study lead author Dr Andrew Lucking, who is a cardiology fellow at the University of Edinburgh in Scotland, UK.

“This study shows that when a person is exposed to relatively high levels of diesel exhaust for a short time, the blood is more likely to clot. This could lead to a blocked vessel resulting in heart attack or stroke,” said Lucking.

Lucking and colleague carried out a double blind, randomized cross-over study on 20 healthy male participatns aged from 21 to 44. Using a specially designed exposure chamber, the men were separately exposed to filtered air (this was the control) and then to 300 mg per cubic metre (mcg/m3) of diesel exhaust fumes, which is roughly the concentration you breathe in while standing by a busy street.

The researchers measured clot formation, blood coagulation, platelet activity and markers of inflammation by attaching each participant to a perfusion chamber and allowing a small amount of blood to pass through it. This was done 2 hours after exposure and then again 6 hours after exposure.

Clot formation was assessed by passing the blood through a special shear chamber that simulates the types of pressure the blood would be under in blood vessels. The researchers tested the blood at high shear and low shear.

Platelet activation was assessed by measuring the number of platelets associated with white blood cells. When platelets are activated they stick to white blood cells like neutrophils and monocytes and form clumps, thereby playing a key role in the formation of blood clots.

The results showed that:

  • Breathing diesel fumes increased clot formation in the low shear chamber by 24.2 per cent compared to breathing filtered air.
  • In the high shear chamber the increase in clot formation from diesel fumes was 19.1 per cent.
  • These effects were observed at both 2 and 6 hours after exposure to diesel fumes.
  • Breathing diesel fumes increased platelet-neutrophil aggregates from 6.5 to 9.2 per cent 2 hours after exposure.
  • It also increased platelet-monocyte aggregates from 21 per cent to 25 per cent 2 hours after exposure.
  • But at 6 hours after exposure the platelet activation increases due to diesel fumes were not statistically significant.

Lucking said: “High levels of traffic pollution are known to increase the risk of heart attack in the immediate hours or days after exposure.”

He said this study showed a “potential mechanism that could link exposure to traffic-derived air pollution with acute heart attack.”

Although these results apply to diesel engine fumes, it’s not clear whether gasoline powered engines would have the same effect, said the researchers. Diesel fumes contain a much higher concentration of very fine particles, they said.

Diesel engines are on the rise because they offer superior fuel economy, but, as Lucking explained:

While diesel engines burn more efficiently, they also put more fine particulate matter into the air.

The researchers said while exercise was good for people with cardiovascular disease, they would not recommend they exercise near traffic congestion.

The UK and Swedish team will be working together on the next step, which is to test the effectiveness of the particle traps fitted to diesel engines to reduce exhaust particles.

“Exposure to air pollution clearly is detrimental and we must look at ways to reduce pollution in the environment,” said Lucking.

An earlier study published in the 13th September issue of the NEJM , also by UK and Swedish researchers, showed that men with coronary heart disease who inhaled diesel fumes experienced a three fold increase in stress on the heart.

Click here for the American Heart Association.

Click here for our report of the September NEJM article on the effect of diesel fumes on men with coronary heart disease.

Written by: Catharine Paddock
Source: Medical News Today

Local Perspective on Hong Kong Air

Local Perspective on Hong Kong’s Air

We all know that our air is polluted, but are we getting the full information of its severity? Are we greatly underestimating the scale of our problem? Douglas Woodring, a concerned resident of Hong Kong and local think-tank, Civic Exchange have come together to answer these questions for Britain in Hong Kong.

UNFORTUNATELY, it took Hong Kong’s largest sporting event, the recent marathon, and one of our all too common “bad air” days, to really get people to understand that we are truly under threat from our air quality. Without the knowledge on where we truly stand, however, the calls to action from the community, and the incentive to make necessary improvements, have yet to occur in a way that would be expected in Asia’s world city.

Who is to blame?

Sadly, the main blame for our air quality is the industrial growth on the other side of the boundary, which we cannot easily rectify, although 70,000 factories in the Pearl River Delta are under Hong Kong ownership and should be held more accountable. This is true, but we also need to be able to demonstrate that we have done everything we can in Hong Kong to tackle our own local air pollution before we can fairly criticise emissions north of the boundary.

With little manufacturing remaining in Hong Kong, the numbers are clear. There are two main components of our local emissions: the excessively high dependence on poor quality diesel vehicles, and air pollution from power generation, particularly from coalfired plants, as natural gas and nuclear generation alternatives are significantly cleaner local fuel sources. It is good news, in that the targets are easy to define, but it is unfortunate for all of us that not enough has been done to make the real changes that are needed. Instead, we are all paying the price of a slow pace of change with our and our families’ health and quality of life.

API Index: HK vs. EU

The first issue to understand is the true level of pollutants in our air. Unfortunately, we are still being given Air Pollution Index (API) readings that are skewed by taking an average reading of various pollutants from the previous 24 hours. Moreover, the Air Quality Objectives that have been introduced for Hong Kong in 1987 are only objectives, but not actual standards. No one is accountable if they are not achieved. If you look at the API index based on European Union standards ( you will find an enormous difference in readings.

The EU claims that it is “very unhealthy” when there are 50 micrograms of pollutants per cubic metre of air, where Hong Kong’s “very unhealthy” level is only reached at 180 micrograms. The day before the Hong Kong marathon, the levels in Central reached almost 300 (based on the EU index). Based on the EU index, the readings are above 200 in Central more often than not, yet our local API index reports the same days as just under 80. With nearly 20-year-old Air Quality Objectives in place, Asia’s world city is out of step with standards set in other parts of the world, and until our API index readings and interpretations of their content are inline with those of the developed world, our decision makers will continue to underplay the urgent need for change.

Road blocks

Hong Kong has the highest percentage of “diesel” road miles driven per capita out of any major developed city in the world. This is a major challenge for Asia’s world city. Tokyo recently embarked on a stringent campaign to limit diesel vehicle use in the city during the day time, while California has declared diesel a carcinogen. The European Commission is also preparing to introduce more stringent limits on diesel particulate emissions, reducing it to a level five times lower than the current Euro 4 standard, as the soot produced primarily by diesel cars has been blamed for a variety of respiratory problems. Daimler Chrysler has recently said that it will equip all of its diesel models with particulate filters starting this year in the Netherlands, Switzerland, Germany and Austria. This is because the community there demands it. Why can’t these filters be used here in Hong Kong?

In contrast, one of Hong Kong’s bus operators is applying for a new 10-year licence, yet the government has yet to set new minimum standards in its type of engines or pollution control equipment, and only 10 out of 752 buses in operation are of Euro III standards. In fact, out of Hong Kong’s licenced bus fleet, 83 per cent out of 4,025 buses are below Euro III standards. One recent response from a government official to the expedition of the replacement of buses to Euro III standards was “that there is a need to adopt a gradual and cautious approach in considering bus replacement.”

Hazardous to health

Locally, Nitrogen oxides (NOx) are primarily produced from power generation and transportation. They affect living materials, building materials and contribute to acid rain. NOx are also a key ingredient of ground-level Ozone, of which diesel fuels are a significant contributor. A 2005 study commissioned by CLSA and prepared by Civic Exchange shows that Ozone concentrations are rising rapidly in Hong Kong, the results of which can be eye and lung irritation, with long-term recurring exposure potentially
causing chronic health problems.

Dialogue has started to introduce Euro V fuels, where the Sulphur content is five times lower than that of current diesel. This will have very little impact, however, if the quality of the majority of Hong Kong’s diesel engines used is not brought up to date. Serious efforts should be made to phase out older diesel vehicles of all types, retrofit others with the most sophisticated particulate traps, and make sure that the fuel used is of the highest quality. This also means making sure that fuels from across the border, where sulphur content is from 50 to 500 times that of Hong Kong, do not make their way onto our roads.

Polluter pays

In terms of energy production in Hong Kong, with the Scheme of Control under review, it would be timely for the introduction of coal-fired emission control equipment to be introduced under a new regulatory regime, which includes environmental performance targets. Hong Kong needs to embrace the “polluter pays principle”. In this regard, a combination of ‘carrot and stick’ comprising bold leadership, world standards, meaningful penalties, attractive incentives and civic education all need to be utilised to deliver necessary improvements.

One solution recommended by economist Philip Bowring’s recent South China Morning Post article suggested an ‘energy tax’, which would simply mean that those who use the most of our resources pay accordingly. Since there is no longer a significant industrial base in this city, this option appears to have merit, also prompting conservation and energy efficiency along the way, which few seem to have the true incentive to pursue today. Until older polluting vehicles are phased out, part of the proceeds from such an ‘energy tax’ could be used to help convert, modify and greatly improve the tens of thousands of outdated diesel vehicles that travel (and idle) on our roads every hour by retrofitting state of-the-art pollution traps and filters.

The options for improvement, that we have in Hong Kong can control, are fairly straightforward, but we all have to want improvement. Unfortunately, not all of us ask for it with such urgency because we are not aware of what is really happening when we are given air pollution readings, which are out of step with international standards. The choice is ours, but we need to put the goal posts in the right places so that we can judge the results and bring accountability to the system.

Cleaning Up The Bus Fleet

Cleaning up the fleet

October 2005

by Fung Man Keung

Lecturer, Department of Automotive Engineering,
Hong Kong Institute of Vocational Education

When concentrating on emission quality only, particulates and nitrogen oxides are the main foci as revealed in Euro IV and V standards.

There is no doubt that liquefied petroleum gas (LPG) is superior to diesel because of its homogenous combustion characteristic, where only very tiny particles and pollutants are emitted. A diesel fuelled engine, with its inherent heterogeneous combustion process, promotes higher concentration in the said pollutants. That’s what we care about.

In Hong Kong, the EPD says that the concentration of diesel engined vehicles is too high. We could add to this and say that the concentration of purely mechanical and unsophisticated / older diesel engined vehicles is too high.

However, applying the state-of-art technology in engine design and after-treatment devices enables them to comply with stringent emission Regulations; therefore, the ban on new light diesel vehicles may not be persuadable enough especially when they comply with latest emission requirements;

You may find that almost half of the new light vehicles in Europe are diesel fuelled and many well known manufacturers are putting a lot of effort into light diesel vehicle research and development and hence manufacturing much cleaner engines.

Diesel possesses a higher energy density compared with various other types of fossil fuels which are commonly used in vehicles. About 40% higher than liquefied petroleum gas (LPG), and diesel engines achieve a higher thermal efficiency compared with spark ignition (LPG or gasoline) engines which may be the driving force for the manufacturers to develop diesel vehicles more aggressively.

From an energy conservation point of view, diesel is therefore the best choice to reduce energy consumption because global warming gases are reduced as a consequence.

In our opinion, new diesel vehicles which comply with the latest emission regulations should have the right to play the fair game with other types of engines;

But… we should make every effort to ensure the emission quality during their service life remains high instead of simply banning them. More frequent monitoring, say biannually, and up-to-date standards for used / older vehicles will be an effective measure to maintain a lower pollution level.

Whichever the type of vehicle, engine deterioration is the prime factor in the decline of emission quality, especially high mileage, public service and commercial vehicles;

Unfortunately, engine deterioration caused by vehicle age and mileage is not part of the existing inspection criteria. Instead, a highly tolerable (easy to meet) emission standard is applied to all vehicles whether they are just 2 or over 10 years old, for instance.

How can owners be encouraged to upkeep their new or lower age vehicle close to the original emission quality? Right now, most vehicles on road just comply with the emission standards of ten years ago or even earlier.

Emission standards for new vehicles are reviewed from time to time in order to aim towards the goal of zero emission; in the meanwhile, if the standards for those vehicles on road are not revised according to their manufacturing year, the road to improving air quality in Hong Kong will be greatly prolonged.

In summary, we would need to realize that all combustion engines are harmful to the environment. Due to the ever developing technologies the differences between the emissions from internal combustion engines burning differing kinds of fuels are diminishing.

We can no longer single out one engine as being very much worse than another (e.g. dirty diesels).

Arguably the key factors to ensuring that engines run as cleanly as possible are

  1. application of the latest technologies
  2. effective maintenance
  3. use of high quality / clean fuels, and
  4. high durability of any given product or system

No matter how clean the emissions of any given internal combustion engines are, such engines will still emit large amounts of carbon dioxide and raw heat, but the toxic gases / particles will likely be greatly minimized.

Any given jurisdiction should take steps to carry out regular emissions checks on all vehicles, say once or twice per year. The data should be collected and analyzed to see where the problem areas are and then corrective actions explored / taken.

Polluting vehicles should be rejected from being reregistered on the road to ensure that good maintenance is applied across the whole Hong Kong fleet.

It therefore follows that having the most stringent regulations is quite useless unless these are matched with appropriately stringent enforcement.

Driven interests of the Minibus Lobby

Friday, September 6, 2002

We believe that some departments under the leadership of Dr Sarah Liao Sau-tung, the Secretary for the Environment, Transport and Works, have in the past not challenged transport lobbyists’ definitions of ”practicable” (”Extending use of LPG in Hong Kong faces physical constraints,” South China Morning Post, August 23) and have even argued that the profits of privately held companies should take precedence over the respiratory health of Hong Kong’s children. Let us take minibuses as an example.

Two-thirds of all green minibuses are under the control of a handful of Hong Kong billionaires. Three companies alone hold 627 licences (25 per cent).

Each licence costs more than $3 million payable to the current licence holder. The minibus lobby claims this is ”widely dispersed ownership”. If you have a licence, and the minibus passes the yearly emissions test, you can renew your licence indefinitely and do not have to compete in the open market. A sweet deal indeed.

The government wants to ban diesel minibuses and has offered a huge subsidy ($60,000 to $100,000 per green minibus) to encourage licence holders to convert away from diesel vehicles. We applaud those who take advantage of the offer. However, the minibus lobby has successfully blocked the ban. Surprisingly, the lobby also vigorously opposed the subsidy because this ”corporate welfare” package was not big enough. They wanted the offer to last 10 years instead of two, and fought to increase minibus seats from 16 to 24.

At the weekend, the minibus lobby used their paid employees (drivers) as front men in a slow-drive protest to try to demand further concessions from the government for red minibuses.

We do not believe the current licensing system is in the best interest of Hong Kong. Licence holders do not have to compete with more environmentally conscious firms who wish to offer better service and use liquefied-petroleum gas or electric minibuses.

LINCOLN CHAN Clear the Air

Street-side pollution problems

Wednesday, July 31, 2002

Street-side pollution problems cannot be ignored

We should all welcome Dr Sarah Liao to the position of Secretary for the Environment, Transport and Works. It is arguably one of the most important of Chief Executive Tung Chee-hwa’s ministerial selections, because of the increasing impact the environment will have on our economy.

One of her first focal points could be to reconsider a recent decision by the government that seemed to go unnoticed by the public – not to convert more than 70,000 diesel light goods vehicles, school buses and vans to liquefied petroleum gas (LPG) for at least another six years. This reminds me of a decision about 10 years ago when the government failed to make the initial change to LPG for our taxi fleet, putting us at least 10 years behind other developed world cities in terms of street-side pollution.

Dr Liao should address this situation head-on and quickly. She mistakenly said that 90 per cent of our air pollution is a result of our neighbours across the border. Many studies have shown that at least 50 per cent of our bad air is of our own making. This is easy to understand when people are seen gasping for air at pedestrian crossings. This problem is not coming from across the border, but from the more than 70,000 diesel vehicles in our streets, literally gassing people as they move.

As this city fights to re-invent itself and become more integrated into the Pearl River Delta, issues of quality will become important differentiators in our economy. When the industrialists have their way, integration with the cities in the delta will mean that people can decide between ”quantity” and ”quality”. This will have a direct impact on real estate prices and our overall economic growth potential. ”Quantity” will be across the border, but will we have ”quality” here to keep Hong Kong a step ahead?

Short-term gains from Disneyland and land-filled developments will not improve our long-term competitive advantage, but an improved quality of life will, and this puts Dr Liao directly in the spotlight as the SAR’s most important minister.

Attending immediately to the more than 70,000 diesel vehicles will be a great step forward, since they are responsible for more than 50 per cent of Hong Kong’s locally-produced air pollution.

This would lead to substantial economic improvements. I hope Dr Liao can rise to the occasion.