Particulate air pollutants comprise material in solid or liquid phase suspended in the atmosphere. Such particles can be either naturally occurring or human activities-related and cover a wide range of sizes.

Naturally occurring particulate matter originates from dust storms, forest fires and sea spray, human activities, such as the combustion of fossil fuels, motor vehicles tailpipes and various industrial and non-industrial processes generate significant amounts of particulate matter.

According to the 2005 World Health Organisation (WHO) Air Quality Guidelines, the evidence on airborne particulate matter and public health is consistent in showing adverse health effects at exposures experienced by urban populations in cities throughout the world.

Ultrafine particulate matter affects the respiratory and cardiovascular systems of humans.

According to the department, it is important that South Africa develops the ambient air quality standard as it will contribute positively in protecting and enhancing the health of South Africans.

“In drafting the national ambient air quality standards, the department has considered these guidelines and other related studies as scientific basis for inclusion of this pollutant in the list of pollutants under the Air Quality Act, and has also taken into account South African conditions such as estimated natural background levels, prevailing ambient air concentrations as well as current trends in air quality management planning across the country,” it said.