The Department of Forestry, Fisheries and the Environment (DFFE) says it is aware of, and is attending to, reports of a strong sulphurous odour detected in various parts of Gauteng, particularly in Ekurhuleni and Johannesburg.

The department says it can confirm that the stench experienced by residents in these areas is likely caused by hydrogen sulphide (H₂S).

“The DFFE wishes to assure the public that the matter is receiving attention.”

In August 2025, then Forestry, Fisheries and the Environment Minister Dion George published, for public comment, a notice of intention to tighten the permitted release of H₂S from coal gasification processes in terms of Section 21 of the National Environmental Management: Air Quality Act (2004).

The proposed amendment seeks to reduce the emission limit of H₂S from 3 500 mg/m³ to 600 mg/m³, which will significantly reduce pollution released into the environment.

Comprehensive comments were received from stakeholders and the DFFE says the notice will be published for a second round of public consultations.

The department says it is anticipated that these regulatory provisions will be finalised and implemented during this year.

The department, meanwhile, notes that recent data from the South African Air Quality Information System shows that levels of sulphur dioxide (SO₂), while elevated, remained in compliance with National Ambient Air Quality Standards during this period.

For H₂S, the DFFE says monitoring data also showed elevated peaks, especially in Secunda, in Mpumalanga, as well as in Springs, Irene, Midstream and Buccleuch, in Gauteng.

“Although there is no National Ambient Air Quality Standards for H₂S for now, these pollution levels were all significantly higher than the World Health Organisation recommended threshold for ambient nuisance odour of 5.02 parts per billion.

“Based on these observations, it is highly likely that complaints raised by the public were prompted by elevated levels of H₂S.”

Meteorological conditions show prevailing south-easterly winds that allowed for the transportation of air pollution from Mpumalanga into Gauteng, particularly over the cities of Ekurhuleni, Johannesburg and Pretoria.

The department notes that this is not the first occurrence of such an event. During February 2022, similar sulphurous odour episodes were experienced across Mpumalanga and Gauteng.

At the time, investigations were conducted by the DFFE together with air quality authorities from Mpumalanga, North West and Gauteng.

Focus was given to Sasol’s Secunda Operations, which is a significant contributor to SO₂ and H₂S emissions.

A multistakeholder task team was subsequently established to investigate complaints and to develop a proactive long-term plan to improve the management of SO₂ and H₂S emissions beyond responses triggered by public complaints.

Following the 2022 incident, two key legislative improvements were identified and are currently being implemented.

This includes the tightening of emission standards and introducing H₂S as a criteria pollutant.

The DFFE says it is anticipated that these legislative amendments will be finalised during this year, adding that these policy interventions are intended to provide long-term strategic solutions to reduce H₂S emissions and limit public exposure.

It notes that, since 2022, the City of Johannesburg has already invested in two additional H₂S monitoring stations in Alexandra and Buccleuch.

“The department will continue to monitor the situation closely and work with provincial and municipal authorities to identify the sources of emissions and ensure compliance with environmental regulations.”