Open AccessSource apportionment of ambient fine and coarse aerosols in Embalenhle and Kinross, South Africa
Author(s) -
Nicola M. Walton,
Stuart J. Piketh,
Pieter Van Zyl,
Willy Maenhaut,
Roelof Burger,
Brigitte Language,
Paola Formenti
Publication year - 2021
Publication title -
clean air journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.239
H-Index - 4
eISSN - 2410-972X
pISSN - 1017-1703
DOI - 10.17159/caj/2021/31/2.11980
Subject(s) - aerosol , air quality index , environmental science , apportionment , environmental chemistry , air pollution , pollution , mineral dust , chemical composition , sea salt , inorganic ions , atmospheric sciences , chemistry , meteorology , ion , geography , biology , ecology , geology , organic chemistry , political science , law
The South African Highveld is recognised as a region having significant negative ambient air quality impacts with its declaration as an Air Quality Priority Area in 2007. Such areas require the implementation of specific air quality intervention strategies to address the air quality situation. A greater understanding of the composition of the atmospheric aerosol loading and the contributing air pollution sources will assist with the formulation and implementation of these strategies. This study aims to assess the composition and sources of the aerosol loading in Embalenhle and Kinross located on the Highveld. Fine (PM2.5) and coarse (PM2.5-10) aerosol samples were collected during summer and winter, which were quantified using the gravimetric method. Wavelength-Dispersive X-Ray Fluorescence (WD-XRF) and Ion Chromatography (IC) analysis were used to determine the chemical composition of aerosols. Mean PM2.5 concentrations in Embalenhle and Kinross ranged from 16.3 to 34.1 µg/m3 during winter and 7.4 to 19.0 µg/m3 during summer. Mean PM10-2.5 concentrations ranged from 10.3 to 114 µg/m3 during winter and 5.9 to 11.2 µg/m3 during summer. Si, Al, S, Na (winter only), Ca (summer only), SO42- and NH4+ were the most abundant species in PM2.5 during both seasons. In PM10-2.5, Si, Al, Na (winter only), SO42- and F- were the most abundant species during both seasons. The elements S and Ca also had high abundances at Embalenhle and Kinross, respectively, during summer. Source apportionment was undertaken using Positive Matrix Factorisation, which identified five sources. Dust, secondary aerosols, domestic combustion, wood and biomass burning, and industry were determined to be the contributing sources. Any measures to mitigate particulate air pollution on the Highveld should consider these key sources.