**4. Conclusions**

A comparative quantitative analysis of 10 genes coding resistance to tetracycline and three sulfonamide resistance genes in two Polish WWTPs in most cases showed an enrichment of selected ARGs after the wastewater treatment processes. The results have confirmed that WWTPs are hotspots for the spread of antibiotic resistance determinants in the environment. This is a serious problem due to the introduction of final effluent into surface waters, as well as the widespread use of reclaimed wastewater as a fertilizer in agriculture soils. The results of this study highlight the need to implement effective actions to prevent the spread of antibiotic determinants in the environment, such as advanced wastewater treatment processes application, the implementation of permanent microbiological monitoring, taking into account the antibiotic resistance aspect, as well as increased control of drug intake and appropriate managemen<sup>t</sup> of medical waste. Moreover, the specially targeted separate treatment of hospital wastewater before discharge to conventional WWTPs is an issue that needs to be addressed by adapting to local circumstances.

**Author Contributions:** Conceptualization, S.S., K.P.B., P.S., J.K. and E.M.; Data curation, M.P.; Funding acquisition, K.P.B. and P.S.; Investigation, M.P. and M.R.; Methodology, M.R. and E.M.; Project administration, M.P.; Resources, M.P., J.K. and D.W.; Supervision, M.R. and E.M.; Visualization, M.P. and E.M.; Writing—original draft, M.P. and E.M.; Writing—review & editing, M.R., S.S., K.P.B. and P.S. 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> no. 538-8610-B774-17/18 and DS 531-8616-D593-19-1E.

**Acknowledgments:** The authors are grateful to the Municipal Wastewater Treatment Plant in Sochaczew (Mazowieckie Voivodeship, Poland) and Municipal Wastewater Treatment Plant Gda ´nsk Wschód (Pomeranian Voivodeship, Poland) for the possibility to obtain the samples and very fruitful cooperation.

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