Qualité de l’air à Osan

What is the current level of air pollution in Osan?

Osan is a city in Gyeonggi Province, South Korea, approximately 35 kilometres south of the capital, Seoul. According to the 2011 census, Osan had an estimated population of approximately 200,000 people.

Towards the middle of 2021. Osan was experiencing a period of air quality that was classified as being “Unhealthy for sensitive groups” with a US AQI reading of 130. This United States Air Quality Index number is an internationally used set of metrics supported by the World Health Organisation (WHO) and is used to compare the air quality in different cities throughout the world using comparable standards. It is calculated by using the levels of the six most commonly found pollutants. If figures are not all available, the figure is calculated using what information is available. In the case of Osan, only PM2.5 was recorded which was 47.4 µg/m³. This figure can be seen to be in four times in excess of the World Health Organisation’s (WHO) recommended level of 10 µg/m³.

With a level such as this, the advice is to close doors and windows to prevent more dirty air from entering the room. Those of a sensitive disposition are advised to remain indoors or if travel outside is unavoidable, then a good quality mask is recommended. All forms of outdoor exercise should be avoided until the air quality improves and it would be advisable to use an air purifier if one is available. The table at the top of this page will help with that decision.

Is the level of air pollution constant throughout the year in Osan?

Air pollution can be very volatile and, as such, can change very quickly depending on many variables, such as wind speed and direction and the strength of sunlight.

Looking back at the figures published by the Swiss air monitoring company IQAir.com for 2020 it can be seen that the best quality of air was enjoyed in September when the level was measured as being “Good” with a figure of just 12 µg/m³. The worst air quality was seen in December with a reading of 36 µg/m³. This figure classified it as being “Unhealthy for sensitive groups”. For the remaining 10 months, the air quality was “Moderate” with readings between 12.1 and 35.4 µg/m³.

Historically, records were kept since 2017 when the level was 28.8 µg/m³, followed by a slight improvement the following year with a figure of 27.8 µg/m³. A decline was seen in 2019 when the figure went back up to 28.2 µg/m³, before a noticeable figure in 2020 of 22.8 µg/m³. However, this may not be a truly accurate reading because of the restrictions imposed due to the COVID-19 pandemic. Many vehicles were no longer used as the drivers were furloughed and not required to commute to and from work. There were also many factories and other non-essential production units which were temporarily closed in an attempt to prevent the spread of the virus.

What are the main sources of air pollution in Osan?

Since the Industrial Revolution, humans have used a lot of fossil fuels and achieved material abundance through industrialization, but the extensive use of fossil fuels has caused various environmental problems. Environmental problems arising from the use of fossil fuels include air pollution, acid rain, environmental damage caused by oil spill accidents, and global warming.

Burning fossil fuels produces harmful pollutants such as carbon monoxide, nitrogen oxides, sulphur oxides, and hydrocarbons, which pollute the air and harm our health. Dust in the air, including fine dust, also causes air pollution, and nitrogen oxides and hydrocarbons combine by sunlight in the air to cause smog. Carbon monoxide, a major source of emissions from automobiles, is a gas produced when fossil fuels are not completely burned, causing headaches and additional stress for people with heart disease.

Nitrogen oxides are produced during the combustion of fossil fuels. Nitrogen monoxide is revealed as a bluish cloud in the city centre, showing the smog phenomenon of smog in large cities over skyscrapers, which irritates the lungs, causes bronchitis or pneumonia, and lowers immunity to respiratory system diseases. Nitrogen oxides are also involved in the generation of smog, which is produced a lot when driving vehicles and burning coal or oil. The hazy pollutant that many cities experience is ozone or smog. Ozone is produced by natural or man-made air pollutants such as nitrogen oxides in response to sunlight or heat. Therefore, it occurs a lot between the hours of 2-5 pm in the summer when the sunlight is strong and clear, and it is particularly high when the wind is not blowing. When people are exposed to ozone, breathing becomes difficult and long-term exposure can cause fatal damage to the lungs. When crops are also exposed to ozone, yields are reduced. Also, when burning fossil fuels, fine dust and smoke and soot is generated, which damages the respiratory system.

Can anything be done to improve the air quality in Osan?

The total amount of air pollutants at worksites is an advanced environmental management system that allocates the total amount of permissible emissions to worksites by year and complies with them. If a business site complies with the quota, the remaining quota can be sold through emission trading. If a business site exceeds the quota, the business site will be subject to a gross overage surcharge and the quota will be reduced for the following year.

The city will strengthen its management by designating the Wondong and Osan-dong areas, which are adjacent to general industrial zones and have many vulnerable groups, as fine dust concentration management zones. In these areas the annual concentration of fine dust is 47 µg/m³, which meets the environmental standard of 50 µg/m³, but the annual concentration of ultrafine dust is 27.6 µg/m³, exceeding the environmental standard of 15 µg/m³. There are 34 centres, including day-care centres, kindergartens, elementary schools, and welfare facilities for the elderly, which are facilities used by the underprivileged.

What detrimental effects on human health does the air in Osan have?

Once fine dust enters the body, immune cells trigger an inflammatory reaction to remove the dust, which can cause allergic conjunctivitis, keratitis, rhinitis, bronchitis, emphysema, and asthma.

When fine dust accumulates in the bronchial tubes, phlegm and coughing become more frequent and the bronchial mucosa becomes dry, allowing bacteria to easily penetrate, increasing the incidence of infectious diseases such as pneumonia.