Air quality in Taipei

What is the air quality index of Taipei?

Taipei is the capital city of Taiwan which is part of the Republic of China. It is situated towards the north of the island together and is an enclave of New Taipei City. In 2019 the population was estimated to be just over 2.6 million people. Towards the end of 2020, the air quality was classed as “Good” according to figures released by IQAir.com. The figure was 48 US AQI. The main pollutant was PM2.5 with a concentration of 11.5 µg/m³. Other recorded pollutants were: - PM10 - 7.5 µg/m³, ozone (O₃) - 14 µg/m³, nitrogen dioxide (NO₂) - 44.2 µg/m³, sulphur dioxide (SO₂) - 3.7 µg/m³ and carbon monoxide - 675.6 µg/m³. All these figures are measured in micrograms per cubic metre.

In 2019 Taipei was ranked as the 17^th cleanest city in Taiwan with an annual average of 13.9 µg/m³. During the months of August and September, it achieved the World Health Organisation’s (WHO) target figure of less than 10 µg/m³. In July the figure was slightly higher at 10.9 µg/m³ and for the rest of the year, it was classed as “Moderate”. When looking back over the previous two years the quality of air is slowly improving. In 2017, the average figure was 15.8 µg/m³ followed by 14.9 µg/m³ in 2018.

Why is Taipei polluted?

The main source of Taipei’s polluted air is from the burning of fossil fuels. Unfortunately, its position makes the situation worse as it is surrounded by high mountains which trap the air and prevent it from being blown away. In 2014 the Taiwan Healthy Air Action Alliance released figures showing the level of Taipei’s poor air quality. The average reading of PM10 was 47.1 µg/m³ which placed it at 1,089 among 1,600 cities around the world. It was also reported that over the last decade, the figure was in excess of the European Union limit value which was 40 µg/m³.

Another main contributor to the poor air comes from “fugitive dust”, which is basically the ultra-fine particles of soil from the earth. This was noted during the 2013-14 winter by the Environmental Protection Administration's (EPA) Department of Environmental Monitoring and Information Management. During the winter months, the rivers flow at a slower rate and are not as deep as at other times of the year. This exposes the river banks which dry out in the strong winds. The north-eastern winds with speeds of up to 3 metres a second cause gusts which pick up dust from the dried out river banks. The level of PM10 pollutant carried by these winds can reach figures of 2,532 µg/m³ as recorded by the Yunlin County's Lunbei Township in 2015.

Levels of the microscopic particulate matter PM2.5 is mainly attributed to vehicle emissions, especially in the large metropolises. Fine particles are also produced by the thermal power plants which are located in the centre of the country, but their exhaust gases are carried by the wind to Taipei.

Research conducted by the National Taiwan University revealed that the average concentration of PM2.5 in Taipei and New Taipei City was 20 µg/m³. It also noticed that the concentration was at its highest from ground-level up to around the height of a three-storey building. This concentration could be as much as ten to twenty times higher, than levels recorded at a greater height. Other hazardous suspended particles such as iron and sulphur also decreased in volume at higher levels. This goes to prove that most of these pollutants are caused by traffic.

The suggested limit for PM2.5 is 15 µg/m³ which is 5 µg/m³ higher than the figure suggested by the WHO. Based on historic data, the average annual levels of nitrogen dioxide (NO₂) have been more than 40 µg/m³ for the past ten consecutive years.

Is air pollution in Taipei getting worse?

In February 2014, the local authorities claimed that there had been at least 7 haze and dust storms over the previous winter and that mainland China was to blame. It was conclusively proved that China’s air pollution directly affects Taiwan every winter due to the strong prevailing winds. The main pollutant is the most dangerous one because of its microscopic size. PM2.5 particulates have a diameter of less than 2.5 microns and are easily carried by the wind. Five other airborne pollutants that are measured are PM10, sulphur dioxide (SO₂), carbon monoxide (CO), nitrogen dioxide (NO₂) and ground-level ozone (O₃). The pollution standards index (PSI) readings at most monitoring stations reached unhealthy levels whilst some in Central and Southern Taiwan recorded levels as being hazardous. There is a noticeable increase in the number of people requiring hospital treatment for respiratory problems in these winter months. Milder symptoms such as eye irritation, coughing and wheezing also increase as do asthma attacks.

Air quality in Taipei city was monitored throughout a ten year period from 1994 to 2003. Having analysed the figures, it was reported as showing an improvement. Four of the main pollutants all showed a decline. These were carbon monoxide (CO), nitric oxide (NO_x), sulphur dioxide (SO₂) and PM10. Ozone (O₃) levels were also recorded and it was noticed that the daily maximum concentrations occurred more frequently in the earlier years. The high concentrations were increasing annually which implies that the situation still needs attention before an improvement can be seen.

What can be done to improve the air quality in Taipei?

In December 2015, the scientific community warned that the prevalence of lung cancer was directly connected to the high levels of pollutants released by the Taichung Power Plant, and the Sixth Naphtha Cracking Plant of the Formosa Plastics Group. It was stated that 70 per cent of the air pollution originated from these two industries. Sulphur oxides were the main pollutants released.

In an old article which was published in 1996, it was revealed that there were almost 9 million motorbikes and 5 million cars on Taiwan’s roads. Motorbikes are the chosen mode of transport for many adults as they are easier to manoeuvre through the congested city centre streets. Motorbikes with two-stroke engines were claimed to be the largest producer of air pollution than any other category of vehicles. The Environmental Protection Foundation and the Green Consumer Foundation have both called for these type of bikes to be banned.

Another more unusual source of air pollution occurs on the first and the 15^th of each Lunar month. This is because of the religious ceremonies which take place at these times. Incense and “Ghost money” are burnt which produce a considerable amount of PM10 particles. Measurements taken in the areas surrounding some of the larger temples showed an increase of between five and sixteen times when compared to other areas. An average of 15.1 µg/m³ were recorded.

The Taiwan Air Quality Monitoring Network (TAQMN) was founded in 1990 when it opened 19 monitoring stations. This number increased to sixty-six in 1993 and to 72 in 1998. The six main pollutants whose levels are recorded are nitrogen dioxide (NO₂), carbon monoxide (CO), ozone (O₃), sulphur dioxide (SO₂), PM2.5 and PM10 and hydrocarbons (HC)s.

Many sources of pollution are now being regulated or controlled. Factories with chimneys without filters are to be regularly inspected and possibly fined for failing to reduce their air pollution. Mobile monitoring equipment can be used near main roads to inspect emissions given off by passing vehicles. Vehicles which visually emit black smoke are to be prevented from travelling into the city centre or into the port areas. The use of computerised traffic signals to reduce idling times is being extended. Streets are to be regularly swept in order to reduce the dust whilst others can be sprayed with water to prevent the dust rising into the air.

What are the effects on health through breathing in Taipei’s polluted air?

Even young, strong healthy people can be affected by air pollution. The concentration of the pollutants and the length of time exposed to them are the two main factors that determine the outcome. For people already suffering from respiratory problems, they will begin to suffer earlier. Other groups of people who need to be more aware of pollution are pregnant women, children under the age of 14 years, those who work outdoors and senior citizens.

High levels of pollution can cause immediate problems such as aggravated respiratory and cardiovascular illnesses. The heart and lungs come under stress as they have to work a lot harder in order to get the required amount of oxygen needed by the body. This can also lead to premature ageing of the lungs and a loss of capacity. Diseases such as asthma, bronchitis, emphysema and some types of cancer are all more commonplace in people who are frequently exposed to high levels of air pollution.

Breathing in ground-level ozone causes wheezing, coughing, chest pain, headaches, dry throats and nausea. It also reduces the body’s ability to fight off infections and weakens the immune system.

Particulate Matter can be a very complex mixture of many things ranging from smoke, soot, metals, nitrates, sulphates, dust, tyre rubber and particles from brake discs. Long term exposure to this can lead to premature death.