Abstract
The occurrence of pharmaceutical compounds in surface water is of global concern. Therefore, this study was conducted to assess the occurrence of acetaminophen, caffeine, ibuprofen, diclofenac, aspirin, diazepam, and tramadol in water samples from hospitals, waste stabilisation ponds, and river in the Obuasi metropolis, Ghana. Solid phase extraction (SPE) sample preparation followed by analysis using high-performance liquid chromatography (HPLC) method was performed on the water samples. The removal efficiency of these pharmaceuticals by waste stabilisation ponds in the study area was also determined. Finally, the ecological risk posed by pharmaceuticals analysed was estimated as risk quotient (RQ). All seven pharmaceuticals analysed were found in all hospital effluent, waste stabilisation ponds, and surface water, indicating their occurrence in the aquatic systems in Obuasi municipality. Acetaminophen was the most prevalent compound found in this study, with a maximum concentration of 23.0 µg/L, while diazepam was the least pervasive compound, with a maximum concentration of 2.0 µg/L. The percentage removal efficiency of the waste stabilisation pond ranged from 61.5 to 82.2%. The RQs ranged from 0.0 to 0.191 for surface water, 0.0002 to 0.209 for waste stabilization pond water, and 0.0–0.295 for hospital wastewater. This indicates that the RQ for all pharmaceuticals analysed could pose low to medium risk. This study has revealed the occurrence and estimated the possible threat posed by these pharmaceuticals; thereby staking a justifiable claim for an urgent action against the removal of pharmaceuticals in water. ,