| Abstract | Wastewater treatment plants (WWTPs) efficiently retain microplastic particles (MPs) generated within urban areas. Among the wastewater treatment steps, disinfection has not been characterized for its potential MPs retention activity, although it has been reported that processes used to abate the bacterial load could also affect MPs concentration. For this reason, we evaluated the MPs concentration across the overall wastewater treatment process and before and after the disinfection step in four small/medium WWTPs located in the north of Italy. Most of the MPs found in the samples were fibers or fragments, smaller than 500 ?m, mainly composed of polyethylene, polypropylene, or polyethylene terephthalate. The retention efficiency at the outlets was higher than 94% in all the plants analyzed. More interestingly, the disinfection treatments adopted by the different WWTPs reduced MPs concentration from a minimum of 9.1% (UV treatment) to a maximum of 67.6% (chlorination), promoting a further increase of the overall retention efficiency of the WWTPs from 0.4 to 0.7%. Quantitatively, the disinfection contributes to the MPs reduction in the outlets by retaining 0.5-6.7 million MPs per day, in WWTPs that discharge 2.7-12 million MPs per day. The results of the present work underline the importance of a careful choice of the steps that constitute the wastewater treatment, including disinfection, in order to minimize MPs discharge into the natural ecosystems. |
| Text | 456893 2021 10.1007/s11356 021 16453 2 Scopus 2 s2.0 85115005681 x Microplastic retention in small and medium municipal wastewater treatment plants and the role of the disinfection Galafassi S.; Di Cesare A.; Di Nardo L.; Sabatino R.; Valsesia A.; Fumagalli F.S.; Corno G.; Volta P. CNR Water Research Institute, Largo Tonolli 50, Verbania, 28922, CNR Water Research Institute, Largo Tonolli 50, 28922, Verbania, Italy, , Italy; European Commission, Joint Research Centre JRC , Ispra, European Commission, Joint Research Centre JRC , Ispra, Italy, , Italy Wastewater treatment plants WWTPs efficiently retain microplastic particles MPs generated within urban areas. Among the wastewater treatment steps, disinfection has not been characterized for its potential MPs retention activity, although it has been reported that processes used to abate the bacterial load could also affect MPs concentration. For this reason, we evaluated the MPs concentration across the overall wastewater treatment process and before and after the disinfection step in four small/medium WWTPs located in the north of Italy. Most of the MPs found in the samples were fibers or fragments, smaller than 500 m, mainly composed of polyethylene, polypropylene, or polyethylene terephthalate. The retention efficiency at the outlets was higher than 94% in all the plants analyzed. More interestingly, the disinfection treatments adopted by the different WWTPs reduced MPs concentration from a minimum of 9.1% UV treatment to a maximum of 67.6% chlorination , promoting a further increase of the overall retention efficiency of the WWTPs from 0.4 to 0.7%. Quantitatively, the disinfection contributes to the MPs reduction in the outlets by retaining 0.5 6.7 million MPs per day, in WWTPs that discharge 2.7 12 million MPs per day. The results of the present work underline the importance of a careful choice of the steps that constitute the wastewater treatment, including disinfection, in order to minimize MPs discharge into the natural ecosystems. Published version http //www.scopus.com/record/display.url eid=2 s2.0 85115005681 origin=inward Articolo in rivista Springer 0944 1344 Environmental science and pollution research international Environmental science and pollution research international Environ. sci. pollut. res. int. Environmental science and pollution research international. Environmental science and pollution research international Print Environmental science and pollution research Print ESPR Print SABATINO RAFFAELLA gianluca.corno CORNO GIANLUCA pietro.volta VOLTA PIETRO andrea.dicesare DI CESARE ANDREA silvia.galafassi GALAFASSI SILVIA |
