Detection, ecological risk assessment and removal efficiency of diclofenac and caffeine in wastewater treatment plant

Pharmaceutical residues that are considered as emerging contaminants have received increased interest in the last years due to their adverse effects on the environment. This is the first study on the assessment of diclofenac and caffeine in municipal waste water of Egypt. The study aims also to report the removal efficiency of waste water treatment plant and the ecological risk assessment of diclofenac and caffeine. Diclofenac and caffeine were detected in both influent and effluent of Tezmant waste water treatment plant (WWWP) in Beni-Suef governorate, Egypt with detection frequency of 100% by using UPLC-MS/MS method. The maximum detected concentrations were 27.85 µg/L for caffeine in February and 1.07µg/L for diclofenac in January, respectively. Caffeine showed higher removal efficiency (95.2%) than that of diclofenac (69.6%). Based on Predicted No Effect Concentration (PNEC) obtained from the literature, it is observed that diclofenac has high risk (RQ>1) on fish and low risk on algae and Daphnia. Meanwhile, caffeine showed low risk on all of the studied species.