**4. Conclusions**

In this study, the analysis of the possibility of using hydroponic cultivation for the removal of 15 pharmaceuticals and endocrine disrupting compounds in municipal wastewater treatment plants

is presented. For the first time, three plants: *Cyperus papyrus* (Papyrus), *Lysimachia nemorum* (Yellow pimpernel), and *Euonymus europaeus* (European spindle) were considered. In order to obtain the most reliable data, the investigation was performed using real MWWTP conditions and with the determination of target compounds not only in raw and treated wastewater, but also in plant materials. The determination of target compounds in raw and treated wastewater samples was performed using a previously proposed method [53]; however, for determining target compounds in plant materials, in this study, a new ASE-SPE-GC-MS(SIM) method was developed and validated. The application of a mixture of MeOH:H2O (1:1, *v*/*v*) at 50 ◦C without the acidification of the ASE extract prior to SPE purification was found to be the most optimal ASE-SPE conditions for the isolation of target compounds from plant material. The MQL values of the proposed method were in the range of 0.4 ng/g d.w. to 2 ng/g d.w.; the intermediate precision measurement was in the range of 0.05 to 21.60%; the mean recoveries in the range of 80% to 102%. Among the 15 investigated, 5 analytes were found in Papyrus (*C. Papyrus*); 5 target compounds in Yellow pimpernel (*L. nemorum*), and 4 in the tissue of the European spindle (*E. europaeus*) plant. The highest concentration of all target compounds was observed for *Lysimachia nemorum* (Yellow pimpernel), therefore, taking into account the summary uptake of target pharmaceuticals and ECDs by the tested plants, this species is the best for supporting conventional MWWTPs. The obtained data proved that the elimination efficiency of the investigated compounds from wastewater was in the range of 35.8% to 100%. Thus, the application of constructed wetlands for supporting conventional MWWTPs allowed a significant increase in their removal from the wastewater stream.

Establishing which plants effectively cumulate certain types of compounds is useful for designing effective constructed wetlands. Moreover, in the future, the proposed method for determining pharmaceuticals and EDCs in plant materials could be used for assessing the quality of food of plant origin in the cultivation of which sewage sludge or purified sewage was used.

**Supplementary Materials:** The following are available online. Table S1 Literature data concerning studies of the usefulness of hydroponically cultivated plants for removing target compounds from the sewage stream; Table S2 Chemical structures and physical and chemical properties of selected non-steroidal anti-inflammatory drugs (NSAIDs), analgesics, β-blockers, β-agonists, antidepressant drugs, and estrogen-based hormones; Figure S1 The mass spectra of target compounds with the MS fragments assignation; Figure S2 Activated sludge chamber with a system of constructed wetlands in the investigated Municipal Wastewater Treatment Plant in Sochaczew (Mazowieckie Voivodeship, Poland); Figure S3 Example chromatogram with marked SIM ions for the determined target compounds in real Papyrus (*Cyperus papyrus*) samples; Figure S4 Example chromatogram with marked SIM ions for the determined target compounds in real Yellow pimpernel (*Lysimachia nemorum*) samples; Figure S5 Example chromatogram with marked SIM ions for the determined target compounds in real European spindle (*Euonymus europaeus*) samples.

**Author Contributions:** Conceptualization, D.W., M.C. and J.K.; Formal analysis, M.P.; Funding acquisition, D.W. and P.S.; Methodology, D.W. and M.C.; Project administration, J.K.; Resources, M.P.; Supervision, J.K.; Validation, D.W.; Writing—original draft, D.W.; Writing—review & editing, J.K. All authors have read and agreed to the published version of the manuscript.

**Funding:** Financial support was provided by the Ministry of Science and Higher Education under gran<sup>t</sup> nos. 539-8610-B334-18/19 and DS 531-8616-D593-19-1E.

**Acknowledgments:** The authors are also grateful to the Municipal Wastewater Treatment Plant (MWWTP) in Sochaczew (Mazowieckie Voivodeship, Poland) for very fruitful cooperation and the possibility to obtain the required samples, and to Agata Miecznikowska for her experimental support.

**Conflicts of Interest:** The authors declare no conflict of interest.
