For the second time this year, a strong sulphur smell has affected Johannesburg, leading to health complaints from residents. The City of Johannesburg detected elevated levels of hydrogen sulphide and sulphur dioxide, likely originating from industrial activities in Mpumalanga's Highveld area. Questions persist about monitoring and enforcement against major polluters.
Residents in Johannesburg reported a noticeable rotten-egg odour over recent days, accompanied by symptoms such as headaches, chest tightness, fatigue, and respiratory issues. This marks the second occurrence of such sulphur-laced air in 2026, prompting renewed attention to air quality challenges in the region.
The City of Johannesburg's monitoring stations in Buccleuch and Alexandra recorded hydrogen sulphide levels peaking at 36-37 parts per billion and sulphur dioxide at around 52 parts per billion. Officials noted that while the concentrations produced a detectable smell, they stayed near background levels and below those typically associated with acute health dangers. Executive director Dr Tebogo Modiba stated, “The ‘rotten-egg’ smell reported by residents is commonly associated with hydrogen sulphide.” Technical teams are examining wind patterns to pinpoint the origin.
Similar to an incident in January, the pollution appears to stem from transboundary movement from the Highveld Priority Area in Mpumalanga, South Africa's most industrialized and polluted zone. This area features Eskom coal-fired power stations and Sasol's petrochemical facilities. Centre for Environmental Rights attorney Ntombi Maphosa explained that weather likely carries emissions from sources including power plants, petrochemical operations, mines, vehicles, and other industries into Gauteng.
Sasol denied involvement, asserting that its Secunda Operations remained stable with emissions within licensed limits, based on internal and independent monitoring. Maphosa highlighted broader issues, noting, “What this smell highlights is not only pollution itself, but the difficulty government still has in properly monitoring and tracing pollution sources.” She pointed to inconsistent ambient monitoring stations in Gauteng, many of which are offline, and the absence of dedicated air-quality officers in some areas.
Eskom has received regulatory leniencies, allowing emissions above original legal standards. The City advised residents to stay indoors, limit outdoor exertion, and watch for symptoms like throat irritation or dizziness, particularly for vulnerable groups. Maphosa warned of long-term risks from repeated exposure, including respiratory diseases, heart conditions, strokes, and cancers, drawing parallels to communities nearer the Highveld sources.
This event underscores ongoing concerns from South Africa's Deadly Air litigation, where courts ruled that excessive pollution infringes on rights to dignity, health, life, and environmental well-being. However, Maphosa observed that enforcement and governance improvements lag behind judicial mandates.