Qualité de l’air à George Town

Is George Town a city with bad air pollution?

George Town is a city located in the island portion of the Malaysian state of Penang, being the capital city as well as the third most populated city in the whole country, being home to some 708 thousand people. It has a long history of many different races and ethnicities mixing together to make it what it is today, with British colonial architecture combined with Malay, Chinese, Indian and other Asian effects combining to create a unique city, one that has earned the status of a UNESCO world heritage site.

In more modern times, it sees itself with a large tourist industry, although of note is that over the course of 2020 this ground to a halt due to the covid-19 outbreak. It is still considered one of the premier places in the world to go for gastronomical reasons, and in times prior to the lockdowns imposed, would have seen a considerable amount of people from all over the world visiting. Whilst this is great for the local economy, it can have an effect on the air quality, due to a massive increase in vehicular usage, which is responsible alone for causing large year round raises in pollution not just in George Town but also worldwide.

Looking at some of the data recorded in the early portion of 2021, there were some relatively high readings of PM2.5 being shown, although this is somewhat of an anomaly due to George Town having some of the cleanest air in the region. Numbers such as 20.1 μg/m³ were recorded in February 2021, putting it in the ‘moderate’ rating bracket, which requires a PM2.5 reading of anywhere between 12.1 to 35.4 μg/m³ to be classified as such. So, whilst it is well known that the quality of air in George Town is good, the reading taken on this particular day also shows that it is on occasion subject to some poorer levels of pollution.

What are some of the contributing causes to air pollution in George Town?

As mentioned before, whilst George Town is renowned for its good quality of air, there would be multiple polluting sources that would be responsible for the occasional spikes in smoke and haze, although due to its fortunate geographical location coupled with meteorological conditions, the high amounts of rain as well as the strong coastal winds are good at removing these buildups of pollution before they accumulate to less appreciable levels, as are often seen in other cities in Malaysia.

Some of the more prominent causes would be vehicular pollution, with a large amount of George Town citizens heavily relying on cars to go about their daily commutes. To further compound this, the road system in Penang relies on one large road situated around the coast for the majority of travel, with the inner heart of the state consisting mainly of hills and forest. So as such, traffic jams are a common and almost infamous feature of everyday life, which can lead to unwanted amounts of fumes and particulate matter to build up in the air. Other sources of pollution would be construction sites, road repairs, as well as the occasional open burning of waste or refuse, along with widespread use of ceremonial joss sticks at the numerous temples in the city.

When would pollution in George Town be at its worst?

As with many cities in Malaysia, George Town would see higher levels of pollution in not only the hottest and driest months of the year (with a lack of rain and high concentrations of sunlight responsible for haze and particulate matter building up, along with the formation of ozone via chemical reactions requiring intense sunlight) but also in September, when the Indonesian forest fires of Sumatra make their way over to the Malaysian peninsula and cause PM2.5 levels to skyrocket. Whilst it is not subject to such oppressive levels of haze buildup as many of the more southern cities are, it would still skew the readings of PM2.5 and PM10 in the air, along with other chemical compounds, and cause heightened pollution readings as well as subsequent related health issues.

The dry season in Malaysia runs from May through to September, and whilst there is still rain occurring during this period, many of the cities in the country see their pollution levels go up as a result of the lessened rainfall, as well as the formation of the previously mentioned ozone, or smog as it is more well known when accumulated on ground level. Whilst it is a vital part of the upper atmosphere, when it forms on the ground level it becomes a hazardous chemical that can cause numerous ill health effects, which will be discussed in following.

What are some health issues related to breathing polluted air in George Town?

During the periods of time when the PM2.5 levels would be higher, there would be a subsequent rise in health issues occurring, as well as the severity in which they take hold. Of note is that whilst George Town has a great air quality, any reading over 10 μg/m³, or the World Health Organizations target goal, has the ability to cause adverse effects.

Some of these would include aging of the lungs, as well as scarring or damage to the lung tissue itself from repeated exposure to particulate matter or smoke inhalation. This can reduce full lung function and decrease an individual’s overall life expectancy. As well as this, it makes those affected more susceptible to further respiratory illnesses and complications. Some of these would include pneumonia and bronchitis, as well as damage to the blood vessels, kidneys, liver and reproductive system, mainly rooted in the fact that fine particulate matter can enter the blood stream via the lungs and cause widespread damage throughout the body.

What are the main pollutants found in the air in George Town?

Due to a large amount of pollution being released from sources such as cars, burnt organic matter as well as construction sites, the pollutants would directly relate. From cars, the main ones would be sulfur dioxide and nitrogen dioxide, as well as carbon monoxide and the formation of ozone (through the various oxides of nitrogen undergoing chemical reaction in intense sunlight to form ozone).

Others would include black carbon and volatile organic compounds (VOC's), both of which are released from cars, heavy machinery and any other open burn sources. Some examples of VOC's include benzene, toluene, xylene, methylene chloride and formaldehyde.