Occurrence of pharmaceuticals in wastewater treatment plants and in receiving water bodies around the city of Rome (Italy)

Pharmaceuticals (PPs) have become ubiquitous in the aquatic environment, detected in surface water and wastewater at ng/L to ?g/L levels. It is well known that municipal wastewater treatment plants (WWTPs) are the major pathways for PPs into the aquatic environment because they are not specifically designed to remove these emerging pollutants. Their presence in the aquatic environment can have adverse effects on biotic communities with changes in morphological and/or metabolic functions and endocrine disruption. The registration and marketing of PPs are exempted from REACH regulation and, currently, a procedure to establish their possible environmental impact is not required. However, the need to monitor pharmaceuticals in water ecosystems has been recently recognized by the EU which has proposed the two steroid hormones 17-?-ethinyl estradiol and 17-?-estradiol and the anti-inflammatory diclofenac to be included in the list of the priority substances regulated by the WFD, with a suggested EQS of 3.5x10-5, 4x10-4 and 0.1 µg/L, respectively. The aim of this study was to provide a better understanding of the occurrence of PPs in surface waters by monitoring in different seasons selected PPs in influent-effluent from WWTPs around the city of Rome (Italy) and from contaminated sites along the urban stretch of the Tiber River. The compounds investigated belong to different classes of pharmaceuticals, such as non-steroidal anti-inflammatories, lipid regulators, antiepileptic and steroidal hormones. The extraction-clean-up from aqueous samples was performed by solid-phase extraction (SPE) followed by an analytical determination with HPLC-MS and HPLC UV-fluorescence. The results showed the occurrence of almost all target compounds in the WWTPs samples with concentrations ranging between 0.1 and 10.9 ?g/L in the influents and between 0.01 and 2.39 ?g/L in the effluents. Mean removal efficiencies varied between 30% and 85%. Along the urban stretch of the Tiber River the PPs concentration levels varied from 50 to 264 ng/L, overcoming, in some cases, the suggested threshold limit. The results confirmed that WWTPs were the main source of river contamination. Although the effluent wastewater input into receiving water should produce a dilution of contamination, the continuous release of PPs into the aquatic environment confers to PPs the characteristic of pseudo-persistence which, in turn, may lead to chronic exposure of organisms at all levels of the food chain.