Byline: Kelebogile Masemola

05 July 2022

The task force probing reports of a sulphurous odour over areas of Gauteng and the North West on 07 June 2022, has concluded that a mix of weather conditions and industrial emissions were probably to blame for the odour. 

The task team is made up of environmental and air quality officials from the Department of Forestry, Fisheries and the Environment and the provincial departments in Mpumalanga, Gauteng, North West and the Free State.   

The sulphur smell may have been caused by industry operations in the Secunda and Mpumalanga regions and as a result of unusual air circulation patterns that saw the smell being blown over Gauteng and parts of the North West during the week of June 5 to 12, 2022, according to task team’s interim internal report, which was delivered to Minister of Forestry, Fisheries and the Environment Barbara Creecy.

The task force is still conducting investigations to see if there was an industrial emergency that might have contributed to the offensive odour that many people had noticed, as well as to see what effect the current meteorological conditions might have had.

At this point, the interim investigations show that a low-pressure system in the north of the Mozambique channel caused a relatively unusual circulation pattern over the region during the days on which the public raised complaints about the strong sulphurous odour.

Due to these circumstances, air pollution from Mpumalanga may have been carried into Gauteng and the North West, particularly over the cities of Ekurhuleni, Johannesburg and Pretoria.

Ambient air quality monitoring observations reflected on the South African Air Quality Information System (SAAQIS) show that despite industry complying with air quality standards in Gauteng and Mpumalanga, ambient levels of sulphur dioxide were higher than usual during the period in question. 

The preliminary investigation shows that none of the facilities in Mpumalanga, North West, Gauteng or the Free State reported any emergency incidents (upset conditions, start-ups, or shut-downs) with the potential to release significant amounts of sulphur dioxide and/or hydrogen sulphide during the week of June 7-12, 2022.

Some of the public complaints about the sulphurous odour coincided with incidents when sulphur dioxide was higher than usual during the period in question However, the elevated readings were unlikely to have caused any health effects on the surrounding communities.

In order to enhance the management of sulphur dioxide and hydrogen sulphide emission sources beyond the responses brought on by public complaints, the Task Team is tasked with researching and making recommendations for potential policy interventions to further reduce hydrogen sulphide pollution and address concerns regarding public safety and the potential long-term health effects of exposure. 

The ongoing investigation will include engaging with industries from identified areas where hydrogen sulphide is of concern, to discuss short-term and long-term management of sulphurous odorants. 

Nationally, that there are four areas where actual or potential large scale hydrogen sulphide emission sources are located in the country.

These are Secunda, Sasolburg/Sedibeng, eMalahleni, and Rustenburg. These areas were, therefore, targeted for investigation.