How serious is the air pollution in Hong Kong?

The air pollution reached a new high on September 24, 2009 in Hong Kong, triggering a warning for people with heart or respiratory illnesses, according to the Hong Kong Environmental Protection Department. I have the impression that the air pollution in Hong Kong is getting worst due to the industrial activities in the nearby southern China, especially the Pearl River delta area. But I have no idea how bad the pollution is. When I am travelling there I feel the air is OK but it is certainly more polluted than Singapore.

Ball pen sketch by Wyser Chu 2009

Hong Kong air pollution

Air pollution causes premature death for thousands of people in Hong Kong each year. It strikes hardest at those who need our care most – children, the elderly and people who are already sick. What happens when you inhale pollutants? Tiny particles (PM2.5, PM10) and gases move deep into the lungs and into your bloodstream. The insides of your lungs can become damaged and inflamed, making it easier for you to get sick. Over time, air pollution can cause permanent changes to your lungs, just like smoking.
Worried about your children breathing dirty air? You have good reason to be. Their lungs are still developing, and since they breathe faster and tend to spend more time outdoors being active, air pollution affects them much more.

According to the Hong Kong Lung Foundation:
– Children living in areas with heavy traffic have more chest problems, such as chest infections and asthma, than those living in cleaner environment;
– During days with high air pollution, more people with asthma, chronic lung diseases or heart diseases have to see their doctors or are admitted to hospital because their disease get worse. Some may even die;
– A small increase in lung cancer risk has also been reported as a result of living in heavily polluted cities;
– Shorter life expectancy of people living in polluted areas compared with those living in cleaner environment by 2 to 3 years.
– Respirable suspended particles (RSP) Causes inflammation of the lungs and airways
– (RSP) Fuel from traffic- Most harmful to health among pollutants, mostly diesel, Construction and road dust. Most harmful to health among pollutants
– Incineration

Dylos laser particle scanner

Dylos laser particle scanner: Nathan Road particle pollution count


Over the last few weeks I brought along a portable laser particle scanner (Dylos). The scanner is able to measure the number of particles of 0.5micron and 2.5 microns. This handy machine allows me to quantify the level of particulate pollution first hand. Air quality rating above 3000 is considered to be very poor, rating below 1000 is good. I was eager to find out if the machine agree with my impression. To be honest, I got a shock the first day. soon after I touch down- the rating on the particle scanner is 10,900 near the west part of Hong Kong island. The normal rating in Singapore is around 1000 to 5000. Over the 10 days I collected data from different part of Hong Kong. The worst rating were obtained along Nathan road (37,000) and Tai-Kok-Tsui (36,000).

The best rating was from Lok-Ma-Zhou (2500), the less busy border between China and Hong Kong. The rating at the Lo Wu station was 10,000. It is necessary to mention that these rating were taking at different days and time, so they should not be taken as an absolute indication for these area.

A day trip (2009-12-22) from Hong Kong to GuangZhou produced an impression of the relative pollution level between the two cities:

Pollution data from Hong Kong to Guang Zhou

Pollution data from Hong Kong to Guang Zhou within a day


@ 7:45 Shek Tong Tsui (Hong Kong Island) 20500
@ 8:50 Sheung Shui (Near border) 26000
@ 10:50 Guang Zhou 30000

It is clear that the pollution level get worst as we approach GuangZhou from Hong Kong.

Anther day trip (2009-12-30) from Hong Kong to Guang Zhou via Shenzhen gave another perspective:

@ 8:35 Shek Tong Tsui (Hong Kong Island) 10000
@ 10:00 Lok-Ma-Zhou (2nd border) 2500
@ 11:15 ShenZhen 8100
@ 18:40 Guang Zhou 17000
@ 20:35 Lu Wu station (1st border) 10000

The air seems to be equally bad from the Hong Kong island all the way up to the Hong Kong/Shenzhen boarder (8100~10000). But interestingly there is an obvious “clean air zone” around the Lok-Ma-Zhou area (2500), which is next to the largest wet land under preservation in Hong Kong.

Lok Ma Chau- better air quality due to large area of wetland

Lok Ma Chau- best air quality in Hong Kong due to large area of wetland

Judging from these data, the pollution level in Hong Kong is indeed worrying. The rating of 10000 to 20000 is 3~6 times the “very poor” indication.
Given that it is a densely populated urban area and it’s proximity to the “factory of the world”, I wonder what can be done to improve the air quality in Hong Kong?

Say No to Pollution in School Bus

School bus in USA

School bus in USA

Every day, half a million school buses safely carry 24 million American children to school, field trips and athletic events.

Unfortunately, most buses are powered by diesel engines that actually pollute the air inside the bus. Studies show the pollution gets trapped inside the bus, where kids breathe it in.
Soot from two sources

Pollution come from emissions from the tailpipe and from the engine. Engine emissions (also referred to as crankcase emissions) enter the school bus cabin mostly through the door and the floorboard.

Because the door is right near the engine, engine emissions get sucked into the school bus, every time the door opens.
Unhealthy diesel exhaust

Diesel engines spew out nearly 40 toxic substances, smog-forming emissions and particulate matter (PM), better known as soot. Coarse and fine particles (PM10 and PM2.5) are breathed deeply into the lungs where they can lodge, creating serious, even life-threatening health problems (more on the health effects of soot and the problem with diesel).

Children are at particular risk because their lungs are still developing. Kids also breathe two times more air per pound of body weight than adults do. The damage to young lungs can result in reduced lung function by adulthood and other dangerous health problems.

Particle Pollution Health Risks

• aggravated asthma
• lung inflammation
• heart problems
• possible cancer
• premature death

Children receive an extra dose of pollution twice a day

pollution in school bus

pollution in school bus

Children riding buses older than 2007 models receive an extra dose of pollution on each ride: monitoring shows that the diesel pollution inside a typical school bus can be up to five times higher than the outside air.

Unless your child’s school bus has been retrofitted with a filter or your child is riding on a brand new 2007 school bus, chances are, your child is breathing in unhealthy pollution levels.
Solutions are at hand

Science indicates that even short-term exposure to elevated particulate levels can have detrimental health effects. The good news is that children do not have to be exposed to diesel school bus pollution. Cost-effective solutions are available. Four Steps to Cleaner Buses.
To cut harmful soot pollution by 90 percent, a bus can be replaced with a new 2007 engine model year bus or retrofitted with a filtering device on the tailpipe, called a diesel particulate filter (DPF).

Engine emissions can easily be eliminated with a crankcase ventilation system (CCVS). A CCVS reroutes the engine emissions to the engine air intake preventing harmful emissions from escaping into the air and the bus cabin.

While working on the long term solution, the immediate action you may take is to install a personal filter (face mask) for your children. However, a surgical mask is useless since the airborne particulates can easily bypass the mask and enter the breathing zone through the gaps. N95 respirator is not available for children because NIOSH never certify any for use on children. Luckily TOTOBOBO mask is now available and it is the first fitting mask designed with the need of children in mind. Even though it is not certified, it is easy to see how it seal the small faces of children. There is even a choice of two different filters; 96% or 94%. The 96% provide higher protection level than N95 mask, and the 94% is only 1% less than N95 mask and has very low breathing resistance.

Reference reading: CLEAN SCHOOL BUS
Idle School bus may be harming your child’s lung

Read more about TOTOBOBO mask for children :

The best fitting mask for children

Say no to pollution in school buses

time for a better mask for children

protect children from incense smoke

How to’s

How to customize TOTOBOBO mask for your children?

How to wash TOTOBOBO mask for reuse?

How to check the mask-to-face-seal without fit-test equipment?

Buy TOTOBOBO mask for children