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Microplastics (MPs) have been detected in numerous ecosystems worldwide. To better understand their distribution and establish a foundation for risk assessment protocols, detailed information on MP concentrations and polymer compositions is essential. This study assessed the presence and chemical composition of MPs, ranging from 5 mm to 125 µm, in the effluents of a Greek wastewater treatment plant (WWTP) over a one-year period to understand the temporal variation in MP input into the receiving water fidentification and mass data were obtained through pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS) analysis. The study found that fibers (50–78 %) were the predominant form of MPs compared to particles, with the most common size range being 125–200 μm for fibers and 200–2000 μm for particles. Py-GC/MS analysis indicated a clear dominance of polyolefins among the polymers analyzed, with MP mass concentrations ranging from 4.5 to 69.29 μg/L. Increased concentrations of MP items and mass were observed following rainfall events (due to elevated discharge and altered hydraulic parameters) and during windy conditions. This underscores the need for improved assessment of background parameters in future MP monitoring strategies. By providing data on MP input in WWTP effluents over a one-year period, this study enhances our understanding of seasonal MP dynamics and can serve as a crucial reference for future measurements.

The global concern about the fate of plastic particles, including microplastics (MPs) and nanoplastics (NPs), in aquatic ecosystems has undoubtedly grown as million tons of polymeric fragments are released in oceans in an annual basis. The ability of these plastic items being transferred into the several aquatic ecosystems in combination with their ability to absorb organic or inorganic pollutants onto their surface, raises the need for a sufficient monitoring of MPs/NPs in complex aquatic environmental matrices. In the frame of these, microscopic techniques are considered as ideal tools to critically assist other analytical techniques due to their fast-screening character or even complete a detailed analysis of plastic particles in some cases. In the light of the above, the present review discusses a group of microscopic techniques used in the analysis of plastic particles isolated from aquatic samples most likely to be important in future monitoring actions, emphasizing on their operating fundamentals, merits and limitations. Moreover, the microscopic techniques are highlighted as green tools in the analysis of plastic particles/fragments due to their minimum need of reagents, solvents, and energy required for the implementation of such a kind of analysis. Finally, the effective combination of microscopic techniques with spectroscopic ones are also presented.

During the past two decades, immobilization of titanium dioxide (TiO2), a well-known photocatalyst, on several polymeric substrates has extensively gained ground since it limits the need of post-treatment separation stages. Taking into account the numerous substrates tested for supporting TiO2 photocatalysts, the use of biodegradable polymer seems a hopeful option owing to its considerable merits, including the flexible nature, low price, chemical inertness, mechanical stability and wide feasibility. The present review places its emphasis on recently published research articles (2011–2021) and exhibits the most innovative studies facilitating the eco-friendly biodegradable polymers to fabricate polymer-based photocatalysts, while the preparation details, photocatalytic performance and reuse of the TiO2/polymer photocatalysts is also debated. The biodegradable polymers examined herein comprise of chitosan (CS), cellulose, alginate, starch, poly(lactid acid) (PLA), polycaprolactone (PCL) and poly(lactide-co-glycolide) (PLGA), while an emphasis on the synthetical pathway (dip-coating, electrospinning, etc.) of the photocatalysts is provided.