Kualitas udara di Bloemfontein

What is the current level of air pollution in Bloemfontein now?

Bloemfontein, also known as Bloem, is the capital city of the Free State Province of South Africa. It is ranked as the seventh largest city in South Africa with an estimated population of approximately 520,000 people. It forms part of the Mangaung Metropolitan Municipality which has a population of 747,431 people.

In the third quarter of 2021, Bloemfontein was experiencing a period of “Unhealthy” air with a US AQI reading of 162. This United States Air Quality Index figure is calculated by collating the recorded levels of six of the most prolific air pollutants. These may include, both diameters of PM (PM10, PM2.5), nitrogen dioxide, sulphur dioxide, ozone and carbon monoxide. If figures are not available for all six, a level can still be calculated by using what information there is. It can then be used as a metric when comparing one city with another, anywhere in the world. In Bloemfontein, there were two recordings made which were for PM2.5 which was 76.5 µg/m³ and sulphur dioxide which was 13.4 µg/m³. The PM2.5 figure is over seven times the acceptable level of 10 µg/m³, as recommended by the World Health Organisation (WHO).

With air pollution as high as this, the recommended procedure would be to stay indoors as much as possible and close all doors and windows to prevent more dirty air entering the rooms. The use of an air purifier would be advantageous but ensure the settings are for recirculated air so that it is not sucking in more air from outside. Those of a sensitive disposition should avoid venturing outside until the air quality improves. If this is unavoidable, then a good quality mask should be worn at all times. There is an app that is available for download from AirVisual which will give you the real air quality in real-time.

Does the level of air quality in Bloemfontein vary throughout the year?

Air quality can be affected by many variables, therefore it can and does change often. Both meteorological and local topography play an important role.

Looking at the figures for 2020, published by IQAir.com, it can be seen that the months of March and May until the end of September revealed the worst quality air over the space of that year. The classification for the quality of air was “Moderate” with readings between 12.1 and 35.4 µg/m³. The months of January, February and April saw an improvement with “Good” quality air. Readings between 10 and 12 µg/m³ qualify as such. The best quality was enjoyed during November and December when the target figure of 10 µg/m³ or less was achieved. November returned a reading of 8.9 µg/m³ whilst December was 9.2 µg/m³. Records for October seem to have been mislaid.

Historically, records pertaining to air quality were held from 2019 when the annual average was a large 42.3 µg/m³ which would place it in the “Unhealthy for sensitive groups” category. In 2020, a noticeable improvement was seen when the figure revealed was 17.2 µg/m³. This may have been affected by the COVID-19 situation as many vehicles were no longer in daily use as staff were encouraged to work from home in an attempt to stop the spread of the virus. Many factories and non-essential production units were also required to close which removed their emissions from the atmosphere.

Where does the polluted air come from in Bloemfontein?

The pollution of the air is mostly caused by the burning of fossil fuels like coal, petrol and oil. Factories and industries release different types of substances into the air, and are apparently one of the biggest sources of pollution. Oil refineries release, for example, ammonia, hydrocarbons, organic acids and sulphur dioxide. Means of transport such as cars, aeroplanes, trains and ships are other important polluters. The fumes from cars' exhaust pipes contain harmful gases such as carbon monoxide, hydrocarbons and nitrogen oxides. Due to the action of sunlight on nitrogen oxides, ozone (toxic compressed oxygen) is formed again. This gas also occurs naturally in the atmosphere and is an important sun filter in the air layers far above, but here close to the earth it is a polluting substance. Together with hydrocarbons, ozone forms the known smog.

The heating of houses, offices and factories also increases the level of pollution in cities, whether it is through the burning of coal, oil or wood or with electricity.

When fossil fuels are burned, the naturally occurring sulphur is converted to sulphur dioxide. This gas ends up in the atmosphere. High temperature flames convert the nitrogen in the air into nitrogen oxides.

Can air pollution in Bloemfontein be controlled?

There are methods to remove the sulphur from coal and oil before it is burned, thereby emitting less smoke. Factories, incinerators and power plants can reduce air pollution with special equipment. Pollution by motor vehicles can be controlled through the use of cleaner fuels, adjustments in the ways the machines operate and certain filters in the exhaust systems.

New industries must, by law, be equipped with adequate air purification facilities and existing industries must take pollution control measures according to a set program. New cement kilns with electrostatic precipitators are capable of reducing dust load to less than 500 mg per cubic meter. Such improvements have also been made in power plants.

What effects does air pollution in Bloemfontein have on human health?

There are many short- and long-term effects that air pollution can have on human health. Indeed, urban air pollution increases the risk of acute respiratory diseases, such as pneumonia, and chronic ones, such as lung cancer and cardiovascular disease. Air pollution affects different groups of people in different ways. The most serious consequences occur in people who are already ill. Furthermore, the most vulnerable groups, such as children, the elderly and low-income families with limited access to health care, are more susceptible to the harmful effects of this phenomenon.

Air pollution has a direct effect on health and especially on the lungs. It is also very harmful to the skin and seems to produce aging of the skin, dehydration of the skin, development of acne, deterioration of cellular material, etc.