Picture: Gulshan Khan/The New York Times.
Picture: Gulshan Khan/The New York Times.

SA ranked second worst hotspot for deadly sulphur dioxide (SO2)

By Sheree Bega Time of article published Aug 19, 2019

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New analysis of NASA satellite data has again shone the spotlight on Mpumalanga's dirty, dangerous air, this time revealing how the area surrounding Kriel is the planet's second worst hotspot for sulphur dioxide (SO2).

The results of a new study by Greenpeace India, released this morning, used NASA satellite data to document the planet's worst sources for SO2, a highly toxic pollutant, which can cause lower respiratory infections, increased risk of stroke and raise the risk of death from diabetes.

Emissions of SO2 contribute to the secondary formation of fine particulate matter (PM2.5), the air pollutant with the largest public health impact.

The Greenpeace study found the area of Kriel is the second worst hotspot because it is home to a high concentration of Eskom coal-fired power stations.

In first place is the massive Norilsk nickel smelter complex in Russia and in third place is Zagroz, an extensive petrochemical operation in Iran.

The results show that Mpumalanga, too, is the world's largest hotspot of SO2 emissions from power generation in the world. Globally, SA is ranked seventh overall in terms of total SO2 emissions.

"There are 12 coal fired power stations in the province, located just 100km-200km from SA's largest populated area, the Gauteng city-region, posing a massive health concern. Power generation from these plants makes the Mpumalanga region the largest hotspot of SO2 emissions from power generation in the world," write Sunil Dahiya and Lauri Myllyvirta, in their paper, Global SO2 Emission Hotspot Database: Ranking the World's Worst Sources of SO2 Pollution.

Globally, power plants and industries burning coal and oil are responsible for two-thirds of the anthropogenic SO2 emission hotspots tracked by NASA satellites. Oil refineries and metals smelters are the other major sources worldwide, says Greenpeace.

Its recent analysis has shown how South Africa is ranked as the fourth worst nitrogen dioxide (NO2) pollution hotspot and the worst NO2 pollution hotspot from power generation alone on the planet.

"This latest analysis once again confirms that SA has the most polluting cluster of coal-fired power stations in the world," says Greenpeace Africa. "The satellite data corroborates existing data, which indicates that Mpumalanga is a deadly global air pollution hotspot, both in terms of NO2 and SO2."

There's a clear reason for this. "Besides having a large concentration of coal-fired power generating and industrial capacity, the emission control performance of (Eskom's) coal-fired boilers is dramatically worse than other countries.

"Eskom's coal-fired power plants are allowed to emit more than 20 times as much SO2 as Chinese and European coal-fired plants. Sasol, one of the largest industrial users of coal in the world, hasn't been required to mitigate its SO2 emissions in any meaningful way either."

Eskom and Sasol are the country's top emitters of the notorious pollutant, says Greenpeace Africa and the Centre for Environmental Rights (CER).

Now, the country's national air quality officer, Dr Thuli Khumalo, is mulling whether to weaken the country’s already "lax" SO2 limits even further, making these around 10 times weaker than the equivalent standard in India and 28 times weaker than the equivalent standard in China. "Under no circumstances should the SO2 limits be weakened. Dr Khumalo should instead be looking to strengthen our minimum emission standards," believes Greenpeace Africa.

Late last year, the doubling of the SO2 standards - from 500 mg/Nm3 to 1000 mg/Nm3 - was introduced by the then Department of Environmental Affairs as an amendment to South Africa's already weak minimum emission standards, without publishing it for public comment as the law requires.

After the department was hauled to court by environmental justice lobby group, groundWork, the notice was withdrawn and then published for public comment in May. 

In June, groundWork, together with the Vukani Environmental Justice Movement in Action, took the government to the High Court for violating the Constitutional right to clean air, on Mpumalanga's Highveld, a declared air priority area. The groups are represented by the CER in the landmark lawsuit.

Research by Myllyvirta, the lead analyst for the Greenpeace's global air pollution unit, has shown how if SO2 standards are doubled, this will cause 3300 premature deaths on the highly polluted Mpumalanga Highveld, from the increased risk of lower respiratory infections, increased risk of stroke, and increased risk of death from diabetes. Around 1 000 of these premature deaths are estimated in Gauteng. These are all avoidable health impacts, Greenpeace stresses.

The increased SO2 pollution, he found, would have profound health impacts on children, the elderly, pregnant women, and those already suffering from asthma, heart, and lung disease.

Doubling the SO2 emission limit will increase population exposure to PM2.5 caused by Eskom's fleet of coal-fired power plants by 70% as "most of the PM2.5 exposure is due to secondary sulphate formation". This is based on atmospheric modelling results in this latest SO2 study.

South Africa is in the "midst of an airpocalypse," remarks Melita Steele, senior climate and energy campaign manager at Greenpeace Africa, in a statement. "South Africa’s air is absolutely filthy, and data analysis consistently confirms this ... We simply cannot afford to waste any more time by delaying industry compliance with air quality legislation or the transition to renewable energy."

Air pollution is a public health emergency with over 90% of the world's population living in areas where the air is unsafe to breathe, write Dahiya and Myllyvirta, yet few countries and regions with the worst air quality have comprehensive inventories of pollution sources.

The NASA OMI satellite has been monitoring air quality in space from 2004, with high consistency. "Its worldwide observation coverage enables us to identify pollution hotspots, which are not listed in emission inventories," their study notes.

It captured more than 500 major point sources of SO2 emissions across the globe, including natural sources such as volcanoes. "Excluding all natural sources from our analysis and only investigating anthropogenic sources of SO2, we found a close correlation of high SO2 emission levels within regions that have high fossil fuel consumption."

"The data shows the world's worst SO2 emission hotspots are found in Russia, SA, Iran, Saudi Arabia, India, Mexico, UAE, Turkey and Serbia.  "In Russia, SA, Mexico and Turkey, emissions are currently not increasing but there is not a lot of progress in reducing them either."

Greenpeace Africa says transitioning towards cleaner air in South Africa is "stunted" by a very high reliance on coal, weak emission standards and a lack of enforcement and compliance.

Major emitters of SO2, China and the US, have been able to reduce emissions rapidly by switching to clean energy sources and, particularly in China, have dramatically improved their emission standards and enforcement.

The report finds that India is the top SO2 emitter in the world, making up more than 15% of global anthropogenic SO2 emissions, having recently overtaken Russia and China, followed by Mexico, Iran and Saudi Arabia with SA ranked seventh total emitter overall.

Myllyvirta said: “The burning of fossil fuels such as coal, oil and gas is the largest source of emissions of SO2 resulting in disastrous air pollution and premature deaths ... It’s fundamental that governments rapidly transition away from fossil fuels and set stronger emission standards as they shift over to sustainable alternatives.”

Air pollution and the climate solution share the same solution, says Greenpeace Africa. "Emission hotspot regions across the world owe it to citizens to stop investing in fossil fuels and shift to safer, more sustainable sources of energy while reducing the impact of existing polluting facilities by adopting stricter emission standards."

What is SO2?

SO2 is created when burning materials that contain sulphur, found in all types of coal and oil. SO2 is a gas contaminating the air we breathe. Emissions of SO2 are a significant contributor to air pollution.

Once in the air, it can also react with water and other substances to form harmful compounds, such as sulphuric acid, sulphurous acid, and sulphate particles. It irritates the nose, throat and airways to cause coughing, wheezing, shortness of breath, or a tight feeling around the chest.

The health impact derives from both direct exposure to SO2 and exposure to fine PM2.5, produced when SO2 reacts with other air pollutants to form sulfate particles. PM2.5 is the air pollutant with the largest public health impact because it's a cocktail of all different kinds of pollution ranging from heavy metals to secondary gaseous pollutants such as sulfates and nitrates.

"These pollutants are so small that they can penetrate deeper into our organs and calls harming every organ in our body, causing everything from dementia and fertility problems to reduced intelligence and heart and lung disease," says Greenpeace. 

The Saturday Star

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