The occurence of pharmaceuticals and other micropollutants in wastewater treatment plant in the aspect of interaction with microplastics

The presence of pharmaceuticals in the aquatic environment is known to scientists and is constantly being investigated. Such micropollutants with bactericidal, virucidal, or fungicidal properties are commonly used in households, which results in their presence in raw sewage flowing to wastewater treatment plants. The content of pharmaceuticals may vary depending on the lifestyle of the inhabitants or the intensity of drug consumption. This study analysed the content of antibiotics, virucidal and fungicidal substances in raw and treated sewage from one of city located in southern Poland with a population equivalent of 680,000. Furthermore, the study was conducted in the summer and autumn-winter seasons.

Microplastics are one of the largest pollutants in the world. Since the 1970s, it has already existed, but there has been no better alternative than plastic. It is related to easy and cheap production, high availability, and specific properties of plastics, such as plasticity, chemical resistance, and lightness.

In the research, samples of stabilized sewage sludge were analyzed in terms of quantitative and qualitative analysis. The separation of microplastics was carried out in two stages. First, the sample matrix was digested with 15% hydrogen peroxide. The next step was density separation, where a saturated solution of calcium chloride was used. Separated microplastics were counted and their sources of origin were analyzed using a Raman confocal microscope and ATR FT-IR spectrometer. The samples were divided according to the month of their collection.
The production of organic-mineral fertilizers from sewage sludge is one of the ecological possibilities of their management. Pharmaceuticals and their derivatives, as well other micropollutants which get in the sludge during the treatment of wastewater, can be a problem. The negative impact of these micropollutants on the environment has been scientifically proven, and the pharmaceuticals and microplastics contained in the sludge may also be detected in fertiliser products.

Acknowledgments: Research supported by the Polish National Agency for Academic Exchange in the Bekker programme (no. PPN/BEK/2020/1/00243/) as well by the Polish National Science Centre (grant no. 2022/45/B/ST10/02108). Research was partially supported by the program ‘Initiative for Excellence – Research University’ for the AGH University of Krakow. Research supported under the Implementation Doctorate in the program of the Ministry of Science and Higher Education.