Source apportionment of fine atmospheric particles in Bloemfontein, South Africa, using positive matrix factorization

Air pollution is of major health and environmental concern globally and in South Africa. Studies on the sources of PM2.5 air pollution in low- and middle-income countries such as South Africa, are limited. This study aimed to identify local and distant sources of PM2.5 pollution in Bloemfontein. PM2.5 samples were collected from June-16 2020 to August-18 2021. Trace element concentrations were determined by EDXRF spectroscopy. The US EPA PMF 5.0 program was used to determine local sources: combustion/wood burning (49 %), industry (22 %), soil dust (10%), base metal/pyrometallurgical and traffic (9.6 %) and water treatment/industry (9.4 %). The HYSPLIT program was applied to determine distant PM2.5 source areas: Mpumalanga province (52 %), Northern Cape province (35 %), Indian Ocean (8 %) and Atlantic Ocean (6 %). The results can be applied in setting up an Air Quality Management Plan for Bloemfontein.