| Abstract [eng] |
From the 20th centure evenly increasing production of plastic and subsequently increasing plastic waste generation cause not only the use of natural resources, greenhouse gas emissions and visually observed environmental contamination with plastic. They also contribute to the formation of microplastics, spreading in nature and effects on living organisms. This encourage research, both in the evaluation of the sources of microplastics and in the search for effective and accessible microplastics analysis in environmental components. As our research objects the biological stabilate from mechanical-biological processing of mixed municipal waste, the compost obtained from food and green waste, and landfills fine fraction have been chosen. Each biological treatment residues contains larger or smaller amounts of plastic waste. The samples of the aforementioned substances were sifted into three granulometric fractions: > 5 mm, 1 mm ÷ 5mm and <1 mm. The largest fraction was rejected. The 1 mm ÷ 5mm faction was investigated visually, and further microplastics were separated using saline solutions of different density. The chemical structure of the separated microplastics was determined by the FTIR method. The <1 mm fraction was treated by a Fenton reagent, thus removing the organic admixtures. Further microplastics were distinguished by the above density method, affected by the Nile red and analyzed by fluorescent microscopy. The results of the study confirmed the abundance of microplastic particles in waste biological treatment products, assuming that this is the presence of macroplastics, mechanical effect during waste processing and biological oxidation. The effect of the latter was further investigated in green waste composting pillow by placing various types of plastics and holding it there for 8 months. Increase in the amount of microplastics and by the SEM method evaluated erosion of PE, PP and PS samples was obvious. The biodegradable sample of PLA was practically fully destroyed. In this way, it becomes evident that plastic waste separate collection and recycling, as well as replacement of conventional plastic with biodegradable plastic significantly reduces the formation of microplastics and its impact to environment and human health. |
