Micropollutants in Lake Como water in the context of circular economy: A snapshot of water cycle contamination in a changing pollution scenario.

• Evaluation of Use and Reuse of water in Como Bay of Lake Como was performed. • Micropollutants were measured in Lake water, rivers, potable water and WWTPs. • The Como Bay receives WWTP discharges from Italy and Switzerland. • Risk assessments for ecosystems and human health generally confirm negligible risks. • Traces of micropollutants such as an antibiotic were found in potable water. In this work we evaluated the contamination of the water cycle in Como Bay by measuring 38 selected pharmaceuticals in two main wastewater treatment plant in Switzerland and in Italy, two influents (River Breggia and Cosia), lake water (epilimnion and hypolimnion), as well as potable water. The collection of comparative information on the presence and environmental fate of these substances contributes to set specific environmental quality standard (EQS). The results presented show that the contamination of the lake reflects national health policies, which deeply influence the usage of chemicals. The outcomes of this study give an overall picture of contamination in the area, showing that concentrations of the measured compounds are generally low and under the commonly adopted ecotoxicological and toxicological thresholds. Only in a few cases did the contamination appear to be noteworthy, for some of the most persistent compounds (antibiotic macrolides, diclofenac, irbesartan, carbamazepine and dihydrocarbamazepine, bezafibrate, furosemide and hydrochlorothiazide). Some concern can be also be raised for the presence of antibiotics (clarithromycin) in drinking water, although at very low levels, due to the problem of antibiotic resistance. [ABSTRACT FROM AUTHOR]