Environmental assessment of Norwegian priority pharmaceuticals based on the EMEA guideline

An environmental risk assessment of eleven pharmaceuticals according to the guideline recommended by the European Medicines Evaluation Agency (EMEA) was performed. Cefuroxime, ciprofloxacin, cyclophosphamide, diclofenac, ethinylestradiol, ibuprofen, metoprolol, paracetamol, sulfamethoxazole, tetracycline and trimethoprim were selected for assessment by the Norwegian Pollution Control Authority. Predicted environmental concentrations (PECs) were calculated according to both the EMEA guideline and a conventional model for comparison and ranged from 0.0002 to 45 μg/L. Available acute and chronic toxicity data were collected from the literature, although no data were available for cyclophosphamide. Toxicity tests showed cyclophosphamide to have relatively low acute toxicity with an EC50 for Pseudokirchneriella subcapitata >100 mg/L and a Daphnia magna reproduction NOEC of 56 mg/L. These and the literature data were used to derive predicted no effect concentrations (PNEC). Risk quotients (PEC/PNEC) were then calculated for all 11 pharmaceutical compounds. Risk quotients greater than 1 were obtained for ciprofloxacin, diclofenac, ethinylestradiol, sulfamethoxazole and tetracycline according to the EMEA guideline. Measured environmental concentrations (MECs) confirmed that the release of ciprofloxacin from wastewater treatment works may potentially be of environmental concern in Norway.