Pharmaceuticals in hospital wastewater: Their ecotoxicity and contribution to the environmental hazard of the effluent

• 197 Pharmaceuticals were sought in hospital wastewater.
• PNEC are available in bibliography for 150 of them.
• Calculation of 127 hazard quotients has been performed.
• Hazardousness of pharmaceuticals is greatly variable.
• 15 Compounds are very hazardous for the environment.

Nowadays, pharmaceuticals are found in every compartment of the environment. Hospitals are one of the main sources of these pollutant emissions sent to wastewater treatment plants (WWTP) that are poorly equipped to treat these types of compounds efficiently. In this work, for each pharmaceutical compound found in hospital wastewater (HWW), we have calculated a hazard quotient (HQ) corresponding to the highest concentration measured in HWW divided by its predicted no effect concentration (PNEC). Thus we have assessed the contribution of each compound to the ecotoxicological threat of HWW taken as a whole. Fifteen compounds are identified as particularly hazardous in HWW. In future more attention should be given to their analysis and replacement in hospitals, and to their elimination in WWTPs. This work also highlights the lack of knowledge of the ecotoxicity of certain pharmaceutical compounds found in HWW at high concentrations (mg L−1). In order to extend this study, it is now necessary to investigate ecotoxic risks linked to various emission scenarios, focusing in particular on dilution in the aquatic environment and the production of metabolites, especially during transit inside WWTPs.