Indoor and outdoor particulate matter concentrations on the Mpumalanga highveld – A case study

Abstract

The household combustion of solid fuels, for the purpose of heating and cooking, is an activity practiced by many people in South Africa. Air pollution caused by the combustion of solid fuels in households has a significant influence on public health. People most affected are those considered to be the poorest, living in low-income settlements, where burning solid fuel is the primary source of energy. Insufficient data has been collected in South Africa to quantify the concentrations of particulate emissions that people are exposed to, especially the respirable fraction, associated with the combustion of solid fuels. The aim of this paper is to gain an understanding of the particulate matter (PM) concentrations a person living in a typical household in a low income settlement in the South African Highveld is exposed to. It also seeks to demonstrate that the use of solid fuels in the household can lead to indoor air pollution concentrations reaching levels very similar to ambient PM concentrations, which could be well in excess of the National Ambient Air Quality Standards, representing a major national public health threat. A mobile monitoring station was used in KwaDela, Mpumalanga to measure both ambient particulate concentrations and meteorological conditions, while a range of dust/particulate monitors were used for indoor and personal particulate concentration measurements. Indoor and personal measurements are limited to the respirable fraction (PM 4 ) as this fraction contributes significantly to the negative health impacts. The sampling for this case study took place from 7-19 August 2014. Highest particulate matter concentrations were evident during the early mornings and the early evenings, when solid fuel burning activities were at their highest. Indoor and personal daily average PM 4 concentrations did not exceed the 24h National Ambient PM 2.5 Standard of 65 µg/m 3 nor did they exceed the 24h National Ambient PM 10 Standard of 75 µg/ m 3 . The outdoor PM 2.5 concentrations were found to be below the standards for the duration of the sampling period. The outdoor PM 10 concentrations exceeded the standards for one day during the sampling period. Results indicate that, although people in KwaDela may be exposed to ambient PM concentrations that can be non-compliant to ambient standards, the exposure to indoor air, where solid fuel is burnt, may be detrimental to their health. Keywords particulate matter exposure, indoor air quality, ambient air quality, personal exposure

Assessment of changes in concentrations of selected criteria pollutants in the Vaal and Highveld Priority Areas

“…As stated by the National Air Quality Officer, in previous State of Air Reports, the compliance with the PM 10 and PM 2.5 standards is a significant problem over the Vaal and Highveld regions with almost all of the monitoring sites being non-compliant with the current NAAQS this is well known and has been previously extensively documented (Venter et al, 2012;Hersey et al, 2015;Wernecke et al, 2015;Feig, et al, 2016;Garland et al, 2017). However, annual SO 2 is generally (with the exception of Witbank) considerably lower than the NAAQS.…”

“…Across the Highveld annual average concentrations of SO 2 were reported as being below the NAAQS (Lourens et al, . At the KwaDela site (located in the Highveld between Ermelo and Secunda), health risks associated with both indoor and outdoor exposure to particulate matter was identified as a risk (Wernecke et al, 2015).…”

A critical review of health risk assessments of exposure to emissions from coal-fired power stations in South Africa

“…it was assumed that the pollutant concentrations predicted for a certain location were inhaled by the people living in that location. This is not the case in areas where people burn solid and liquid fuels in their homes for cooking or space heating, as shown by measurements collected by Wernecke (2018) in the low-income areas of Kwadela and KwaZamokuhle on the Mpumalanga Highveld (Table 6). Coal is burnt for heating in around 70% of households in Kwadela, and 60% of households in KwaZamokuhle.…”

“…Indoor PM 4 concentration and personal PM 4 exposure levels in two low-income areas on the Mpumalanga Highveld (concentrations in µg/m 3 ;Wernecke 2018) …”

Global Statement on Air Pollution and Health: Opportunities for Africa

“…Certain vulnerable groups may be simultaneously exposed to air pollution from multiple sources – sometimes at highly elevated concentrations [3]. For example, people living in informal settlements without a connection to the electricity grid, located close to mine tailings facilities or industrial sites, and in areas with unpaved roads (Figure 1c).…”