AIR quality across South Africa, measured at 76 monitoring stations across the country, exceeded the country’s and the World Health Organisation’s limits for aerosols, experts said at a Council for Scientific and Industrial Research (CSIR) seminar on Tuesday.

Aerosols — which are small, airborne particles suspended in the atmosphere — are the single biggest air pollution health risk and can lead to respiratory complaints such as asthma or even premature death.

The worst-affected areas were greater Cape Town, Witbank and Limpopo’s coalfields, in terms of one of two metrics measured.

South Africa monitors two sizes of aerosols to determine pollution levels: PM-10 and PM-2.5, CSIR climatologist Rachel Garland said.

The National Environment Management Air Quality Act provides for fines of up to R5m or jail terms of up to five years for a first offence. A R3m fine was recently imposed on Witbank’s Silicon Smelters for committing an act "which caused, or was likely to cause, significant pollution".

But North-West University climatologist Stuart Piketh said few were prosecuted for such crimes. "Is there any point spending millions in monitoring (air quality) if nothing is done about it?"

Webber Wentzel partner Marius Diemont said all provinces had not yet submitted the required air quality management plans.

Of the 76 ambient air quality monitoring stations in SA, 64 were government-owned and 12 owned by industry — Sasol and Eskom — South African Weather Service air quality information manager Gregor Feig said yesterday.

Monitoring happened mostly in large metropolitan areas and "air quality priority areas" such as Secunda and Witbank, but was largely absent from "high-density rural areas" such as around Polokwane, he said.

Most aerosols came from burning coal, Prof Piketh said, adding that Cape Town had the highest levels of airborne aerosols in the country because of the domestic burning of coal.

"Our population in the townships is choking to death on a daily basis," he said.

Readings at aerosol monitoring stations in the City of Johannesburg region have exceeded regulations since 2006.