Abstract
The consumption of pharmaceuticals during the COVID-19 pandemic increased significantly.
As such, over-the-counter drugs such as acetaminophen (ACT), ibuprofen (IBU),
metoprolol (MET), and propranolol (PRO) were among the pharmaceuticals that were
widely used to contain COVID-19 symptoms. Therefore, this study investigated the occurrence
of ACT, IBU, MET, and PRO in wastewater and river water systems, focusing
on two provinces in South Africa (Gauteng (GP) and KwaZulu-Natal (KZN)). Generally,
WWTP influents had the highest concentrations in both provinces. ACT, MET, and PRO
were frequently detected compared to ibuprofen, particularly in KZN, during the second
wave of the COVID-19 pandemic. However, a low detection occurred during the fourth
wave of the COVID-19 pandemic. The concentrations of ACT, IBU, MET, and PRO in
influent wastewater samples ranged from ND-480 μg/L, ND-54.1 μg/L, ND-52.8 μg/L, to
ND-13.1 μg/L, respectively. In comparison with influent samples, ACT, IBU, MET, and PRO
concentrations of effluent wastewater samples were generally at lower concentration levels:
ACT (ND-289 μg/L), IBU (ND-36.1 μg/L), MET (ND-13.9 μg/L), and PRO (ND-5.53 μg/L).
The removal efficiencies of the selected pharmaceuticals in KZN WWTPs ranged from 6.1
to 100% and −362.6 to 100% in the GP province. The ecological risk assessment results
showed a low to high ecological risk against fish, Daphnia magna, and algae due to the
presence of these pharmaceuticals.