The Smoky Haze Over Witbank: Uncovering Pollution Sources

Witbank, in Mpumalanga, South Africa, has been described as having the dirtiest air in the world. Greenpeace analysis of satellite data from 1 June to 31 August 2018 revealed that Mpumalanga is the largest NO2 hotspot across six continents. The area has been plagued with deadly air quality for decades, with a high concentration of coal-fired power plants, a coal-to-liquids plant, and a refinery contributing large amounts of pollution. The burning and extraction of coal have devastating impacts on the health of people living in the area, with thousands of cases of bronchitis and asthma in adults and children annually.

Coal-fired power stations

The burning of coal releases harmful chemicals into the air, including sulphur dioxide, heavy metals like mercury, and fine particulate matter. These emissions have severe health impacts on the local population, causing chronic respiratory illnesses such as asthma, bronchitis, and lung cancer, and contributing to strokes, heart attacks, birth defects, and premature deaths. According to a report by UK-based air quality and health expert Dr Mike Holland, air pollution from coal-fired power stations in South Africa causes more than 2,200 deaths every year, with thousands of additional cases of bronchitis and asthma in adults and children.

The problem is exacerbated by South Africa's relatively weak Minimum Emission Standards (MES), which allow coal-fired power stations to emit up to 10 times more NO2 than permitted in countries like China or Japan. Despite this, many of Eskom's coal-fired power plants do not comply with the MES, and the company has repeatedly sought postponements from meeting the required standards.

The South African government has faced litigation from environmental and health advocates, who argue that the government has violated the Constitutional right to a healthy environment for those living and working in the Highveld Priority Area (HPA). In response, the government has acknowledged the poor air quality in the region, but its efforts to improve the situation have been limited, and activists claim that little has changed in recent years.

The pollution from coal-fired power stations in Witbank is not only a local issue but also a global concern. Greenpeace has identified Mpumalanga as the world's largest NO2 air pollution hotspot, with emissions from the province's power stations impacting the health of millions of people in nearby cities like Johannesburg and Pretoria. The situation in Witbank highlights the urgent need for stronger air quality regulations and a transition away from coal-fired power generation to protect public health and the environment.

Sulphur dioxide emissions

Sulphur dioxide (SO2) emissions are a major contributor to air pollution in Witbank, also known as eMalahleni, in South Africa. SO2 is a toxic gas that can have significant adverse effects on human health and the environment.

The primary source of SO2 emissions in Witbank is the burning of coal, particularly in coal-fired power stations. Witbank is home to several coal-fired power plants, including Duvha, Matimba, and Kendal, which are owned and operated by Eskom. These power stations burn coal that has a high sulphur content, which, when burned, releases large amounts of SO2 into the atmosphere.

The lack of adequate controls and maintenance at these power stations exacerbates the problem. In the 1990s and early 2000s, stricter controls were in place to curb SO2 emissions, including regular audits and competitions to reward the best-performing power stations. However, these measures have since been relaxed, and Eskom has been accused of failing to comply with the Minimum Emission Standards set to limit pollution.

The consequences of these high SO2 emissions are dire. SO2 emissions contribute to the formation of fine particulate matter (PM2.5), which has been linked to severe health conditions, including lung cancer, respiratory infections, and an increased risk of stroke and death from diabetes. According to a report by Dr. Mike Holland, air pollution from coal-fired power stations in South Africa causes more than 2,200 deaths per year and thousands of cases of bronchitis and asthma in adults and children.

To address this issue, the implementation of flue gas desulphurisation technology has been proposed, which could reduce SO2 emissions by up to 90%. This technology is being built into Eskom's new power station at Kusile in Mpumalanga, but the company has requested delays in introducing it at other plants, citing water constraints and the need to meet national electricity demands.

Heavy metals in the air

Air pollution in Witbank, South Africa, is largely caused by coal-fired power plants in the area. A 2017 report by UK-based air quality and health expert Dr Mike Holland revealed the shocking health impacts of air pollution from the burning of coal in South Africa. The report estimated that air pollution from coal power plants caused about 2,239 deaths per year, with 157 of those from lung cancer and 73 from chronic obstructive pulmonary disease.

Coal-fired power plants emit toxic chemical compounds such as sulphur dioxide, heavy metals, and fine particulate matter. Heavy metals are well-known environmental pollutants due to their toxicity, ability to remain in the atmosphere for long periods, and their accumulation in the human body through bioaccumulation. They are characterised by their high atomic mass and toxicity to living organisms.

Heavy metals can be derived from both natural and anthropogenic sources. Natural sources include the weathering of rocks, while anthropogenic sources include industrial activities such as metallurgy, refractory, and chemical industries. Metal processing, tannery facilities, chromate production, and stainless steel welding are some of the industries that contribute significantly to chromium release.

The toxicity of heavy metals depends on factors such as the dose, route of exposure, and chemical species, as well as the characteristics of exposed individuals, such as age, gender, genetics, and nutritional status. Arsenic, cadmium, chromium, lead, and mercury are particularly toxic and are known to induce organ damage and cancer even at lower levels of exposure. Lead exposure, for example, has been linked to genetic damage, gene mutations, and developmental abnormalities.

The presence of heavy metals in the air is a major environmental concern due to their potential impacts on public health and the ecosystem. Nanotechnology-based treatments are being developed to analyse and remove heavy metals from various matrices, such as food and water resources.

Poor government regulation

The South African government has faced criticism for its weak Minimum Emission Standards (MES), which allow coal-fired power stations to emit up to 10 times more NO2 than permitted in countries like China and Japan. Despite this, many of Eskom's highly polluting coal-fired power stations fail to comply with these already lenient standards. In 2015, Eskom was granted a five-year postponement from meeting the MES, and they have since sought further delays, highlighting the government's ineffective enforcement of air quality regulations.

In 2017, a report by UK-based air quality and health expert Dr. Mike Holland revealed the devastating health impacts of air pollution from coal-fired power plants in South Africa. The report estimated that air pollution from coal burning resulted in 2,239 deaths annually from causes such as lung cancer, ischaemic heart disease, and chronic obstructive pulmonary disease. Furthermore, thousands of cases of bronchitis and asthma in adults and children were attributed to coal-fired power station emissions, incurring substantial costs on the country's healthcare system and lost productivity.

The Department of Environmental Affairs (now the Department of Forestry, Fisheries, and Environment) acknowledged in 2012 that the Mpumalanga region, including Witbank, was an air pollution hotspot with extremely poor air quality. Despite publishing an air quality management plan (the HPA AQMP) to address the issue, little progress has been made in improving air quality in the area. This inaction has led to litigation, with applicants claiming that the government has violated the Constitutional right to a healthy environment for those living and working in the Highveld Priority Area (HPA).

The government's failure to adequately regulate and enforce air quality standards has contributed significantly to the air pollution crisis in Witbank. Weak emission standards, lack of compliance, and delays in implementing improvements have had severe consequences for the health and well-being of residents in the region. It is essential that the government takes urgent and effective action to address this critical issue.

Water contamination

The burning of coal releases toxic chemical compounds such as sulphur dioxide, heavy metals like mercury, and fine particulate matter. These pollutants contribute to water contamination and have severe ecological consequences. For example, rivers and associated ecosystems in the area are negatively affected by the high levels of heavy metals in the air.

In addition to the direct environmental impacts, coal-fired power stations in Witbank are responsible for thousands of cases of respiratory illnesses in adults and children annually. This includes cases of bronchitis, asthma, and lung cancer, as well as contributing to strokes, heart attacks, birth defects, and premature deaths. The health impacts of air pollution from coal-fired power stations in South Africa are estimated to cost the country more than R30 billion annually through hospital admissions and lost working days.

The South African government has faced litigation from environmental organisations and activists who argue that the government has violated the Constitutional right to a healthy environment for those living and working in the Highveld Priority Area (HPA). While the government has acknowledged the poor air quality in the region and published an air quality management plan in 2012, little progress has been made to improve the situation.

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