Target and Suspect Screening of Pharmaceuticals and Their Transformation Products in the Klip River, South Africa Using Ultra High-Performance Liquid Chromatography-Mass Spectrometry.

In spite of recent reports on the presence of pharmaceuticals in African water bodies, their prevalence is still not sufficiently quantified. This is because the reports are still few with major focus on a limited number of pharmaceuticals. In this study, the suspect screening of 92 compounds (mainly pharmaceuticals and their transformation products) along the Klip River, South Africa was conducted, followed by the target monitoring of 21 of the detected pharmaceuticals. The experimental approach was based on solid-phase extraction followed by UHPLC-QTOF-MS analysis. The results revealed 47 pharmaceuticals, 31 of which were detected for the first time in South African waters. Seven detected pharmaceuticals; propyphenazole, sulfamerazine, levamisole, tryptophan, dibucaine, albuterol and fenpropimorph are not approved medications in South Africa. Six pharmaceutical metabolites were detected for the first time in South Africa. Pharmaceuticals with highest concentrations in river water were flumequine (0.257 µg L-1 ), oxolinic acid (0.355 µg L-1 ) and acetaminophen (0.432 µg L-1 ). Oxolinic acid presented the highest hazard quotient of 48.6, indicating risk of toxicity towards aquatic organisms. Hazard quotients for other pharmaceuticals were below 1, except that of flumequine which reached 1.285. These results suggest a need for further research into the fate of pharmaceuticals in surface waters, and a quantification of the risks associated with the identified drugs as these are likely to accumulate in fish/aquatic organisms' tissues thus affecting humans. This article is protected by copyright. All rights reserved.