Application of Molecularly Imprinted Polymers for Detecting Pharmaceuticals in Sediments, River Water and Stevia rebaudiana in Durban, South Africa

Pharmaceuticals have been the focus of research into South Africa’s water resources for the past ten years and more. Five pharmaceutical residues were examined in this investigation in plant, sediment, and river water samples from Durban, SA. Fenoprofen, diclofenac, naproxen, gemfibrozil, and ibuprofen were the compounds of interest; they are some of the most widely used and often prescribed medications globally. Compound concentrations found in sediments and river water ranged from 0.2 to 12.0 ng g−1 and 0.2 to 5.1 µg L−1, respectively. Different plant parts (roots, stems, and leaves) had varying quantities of the target compounds in the Stevia rebaudiana species. The most prevalent drug in Stevia rebaudiana was ibuprofen, which was discovered in roots at the highest concentration of 7.2 ng g−1. Although there was no apparent trend in the amounts identified in different areas of Stevia rebaudiana in this preliminary analysis, it is hypothesized that these pharmaceuticals penetrate into the aquatic plant roots from water and then move into the stem and leaves. The partitioning coefficients (L kg−1) varied from one sampling location to another; fenoprofen, diclofenac, naproxen, gemfibrozil, and ibuprofen and diclofenac ranged from 0.1 to 4.0, 0.9 to 6.8, 0.8 to 3.7, 0.2 to 8.5, and 0.6 to 5.6, respectively. This suggests that environmental factors, including climate and the existence of additional pollutants from water, as well as variations in physicochemical properties, may have an impact on the fates of these pharmaceuticals. Overall, it was found that the target compounds were present in river water, sediments, and Stevia rebaudiana. This suggests that Stevia rebaudiana may reduce water pollution by absorbing pharmaceuticals through its roots.