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The presence of organic pollutants in the aquatic environment, usually found at trace concentrations (i.e., between ng L −1 and μg L −1 or even lower, known as micropollutants), has been highlighted in recent decades as a worldwide environmental concern due to their difficult elimination by conventional water and wastewater treatment processes. The relevant information on constructed wetlands (CWs) and their application for the removal of a specific group of pollutants, 41 organic priority substances/classes of substances (PSs) and 8 certain other substances with environmental quality standards (EQS) listed in Directive 2013/39/EU as well as 17 contaminants of emerging concern (CECs) of the Watch List of Decision 2015/495/EU, is herein reviewed. Studies were found for 24 PSs and 2 other substances with EQS: octylphenol, nonylphenol, perfluorooctane sulfonic acid, di(2-ethylhexyl)phthalate, trichloromethane, dichloromethane, 1,2-dichloroethane, pentachlorobenzene, benzene, polychlorinated dibenzo-p-dioxins, naphthalene, fluoranthene, trifluralin, alachlor, isoproturon, diuron, tributyltin compounds, simazine, atrazine, chlorpyrifos (chlorpyrifos-ethyl), chlorfenvinphos, hexachlorobenzene, pentachlorophenol, endosulfan, dichlorodiphenyltrichloroethane (or DDT) and dieldrin. A few reports were also published for 8 CECs: imidacloprid, erythromycin, clarithromycin, azithromycin, diclofenac, estrone, 17-beta-estradiol and 17-alpha-ethinylestradiol. No references were found for the other 17 PSs, 6 certain other substances with EQS and 9 CECs listed in EU legislation. [ABSTRACT FROM AUTHOR]

Ozone-based water treatments were investigated to simultaneously remove organic micropollutants (OMPs) and bacteria from surface water samples collected in a river reservoir supplying a drinking water treatment plant. Among the 21 environmentally relevant OMPs selected, 15 were detected at low (< 20) ng L−1 level. Surface water samples were then spiked with these 21 OMPs (100 ng L−1) and the ozone-based treatments were tested with excess of ozone and high hydraulic retention time (HRT: 41 min). Regardless of the treatment applied (O 3 , O 3 /UVA-LEDs, and O 3 /H 2 O 2), removal efficiencies higher than 85% were always obtained for 20 out of 21 OMPs (and lower than 50% for PFOS). Thus, single ozonation was considered the best treatment solution, being afterwards investigated in terms of water disinfection at milder operating conditions (3 mg O 3 L−1 and HRT: 10 min). Under these conditions, the removals of spiked OMPs were also higher than 85% (except for PFOS), whereas bacteria (i.e. , total heterotrophs at 37 and 22 °C, E. coli and enterococci) decreased to values lower than the permissible levels for drinking water, even upon storage for 3-days. However, lower ozone doses (1.5 mg O 3 L−1) could not prevent the regrowth of total heterotrophs incubated at 37 °C, which reached levels five times higher than those recommended. Because drinking water treatments should not only consider OMPs abatement but also microbial inactivation for long periods of time, the results herein obtained point out the importance of using ozone doses capable of accomplish both targets when using single ozonation. [Display omitted] • Ozone-based treatments investigated for surface water intended for consumption. • 20 out of 21 organic micropollutants were removed (>85%) by single ozonation. • PFOS removals were lower than 50% regardless of the treatment process tested. • The treated water had sufficient microbial quality for human consumption. • Ozone doses lower than 3 mg O 3 L−1 are not recommended due to bacteria regrowth. [ABSTRACT FROM AUTHOR]