State of ambient air quality in a low-income urban settlement of South Africa.

ABSTRACT

Air pollution remains one of the leading global environmental-health challenges the world is facing today, particularly within urban environments. amidst the COVID-19 pandemic, air pollution has been brought back into the spotlight as both attack the human respiratory systems. The purpose of the study was to investigate the quality of ambient air in a low-income urban settlement of Jabavu located within the City of Johannesburg during the year 2018. Air pollution and meteorological data were gathered from the South African Air Quality System network. The study focused on three pollutants namely PM10, SO2 and O3. Findings were that the seasonal ambient mean concentrations for PM10 in summer was (28.99 µg/m3), autumn (33.32 µg/m3), winter (61.71 µg/m3) and spring (48.44 µg/m3). On the other hand, the seasonal ambient mean concentrations for SO2 was summer (4.45ppb), autumn (3.19ppb), winter (5.65ppb) and spring (3.54ppb). The O3 seasonal ambient mean concentrations were summer (40.97ppb), autumn (21.01ppb), winter (15.90ppb) and spring (33.59ppb). Furthermore, the study observed that in summer, winter and spring the dominant long-range transport air masses originated from the South Atlantic Ocean, Madagascar Island-India Ocean and the Indian Ocean while in autumn the dominant air masses are short-range inland air masses. For SO2 and PM10, ambient concentrations were found to be more problematic during winter; while for O3 substantial levels were unexpectedly recorded in summer. When analysing the diurnal profiles of PM10, SO2 and O3, each of these pollutants revealed a unique distribution pattern, which, despite having seasonal variance, was consistent throughout the year. For instance, irrespective of the season, PM10 mostly peaked in the mornings and evenings; meanwhile SO2 and O3 often spiked during the midday and mid-afternoon, respectively. These findings indicate that air quality within this low-income settlement is poor. To improve air quality within low-income settlements there is a need for a shift from reliance on solid fuels to cleaner energy sources such as LP gas, biogas and solar accompanied by an increase in community awareness about air quality issues. This study contributes to knowledge building within the air quality monitoring scientific community while for policymakers it assists in policy formulation to enable air quality management.