Gauteng: The Department of Forestry, Fisheries and the Environment (DFFE) has assured the public that it is attending to reports of a strong sulphurous odour detected in various parts of Gauteng, particularly in Ekurhuleni and Johannesburg. The department has confirmed that the stench experienced by residents in these areas is likely caused by hydrogen sulphide (H2S).
According to South African Government News Agency, the department received reports of the strong sulphurous odour on 10 March 2026. Air quality monitoring information from the South African Air Quality Information System (SAAQIS) indicated that levels of sulphur dioxide, while elevated, remained within compliance with National Ambient Air Quality Standards during this period. Monitoring data showed elevated peaks of hydrogen sulphide, especially in Secunda, Springs, Irene (Pretoria), Midstream, and Buccleuch air quality monitoring stations. Although there are currently no National Ambient Air Quality Standards for hydrogen sulphide, these pollution levels were significantly higher than the World Health Organisation's recommended threshold for ambient nuisance odour.
The department explained that meteorological conditions, particularly south-easterly winds, facilitated the transportation of air pollution from Mpumalanga into Gauteng, affecting areas like Ekurhuleni, Johannesburg, and Pretoria. Exposure to hydrogen sulphide may lead to irritation of the eyes and respiratory system, dizziness, headaches, nausea, and other health issues. The department urges the public to report persistent strong odours to local environmental health authorities and seek medical attention if experiencing persistent discomfort.
Following a similar odour episode in 2022, the government is implementing legislative measures to tighten minimum emission standards and introduce hydrogen sulphide as a criteria pollutant. These steps aim to reduce emissions and establish National Ambient Air Quality Standards for hydrogen sulphide, aligning with international health protection guidelines. Consultations with provinces and municipalities on these standards are currently underway.