EXPERIMENTAL STUDY OF DEGRADATION OF BIO-BASED PACKAGING, PAPER AND CONVENTIONAL PLASTIC BAGS IN SOIL

Abstract

The increased use of plastic products and the shift to single-use plastics have led to an excessive accumulation of plastic waste in the environment. The durability of plastic is estimated at hundreds to thousands of years. Over the past two decades, bioplastics have been proposed as an alternative to traditional synthetic polymers, but issues related to their degradation remain poorly studied. The purpose of this study is to compare the degradation rates of paper and conventional disposable plastic bags, as well as bags labeled “biodegradable”, in soil. Research methodology. The research was done in the city of Bohodukhiv (Kharkiv Oblast) from early July till late November 2024. The site for soil sampling was selected in a garden with spontaneous herbaceous vegetation on the territory of a private household. The soil was transferred to 15 transparent plastic containers of the same size and shape. Five of the containers were filled with fragments of a regular disposable plastic bag, five with biodegradable plastic bags, three with fragments of a paper bag, and the remaining two containers were left with bare soil (control). All containers were kept in the same conditions. The analysis was carried out according to the characteristics of the loss of physical integrity of the bags on the 36th, 85th, and 141st day after the start of the experiment. The surface area of patches that underwent destruction was measured using the ImagJ software. Novelty. A linear regression model of the process of bio-based packaging degradation was built. Conclusions. Biodegradable bags begin to decompose faster than conventional disposable plastic bags, with the difference statistically proven. This difference is evident at least after a month from the start of the experiment. In almost three months of the experiment, the level of bio-based packaging degradation reached 10 %, and they did not undergo complete degradation during this time as expected prior to the experiment. After almost six months of experimentation (i.e., twice as long as the manufacturer claimed), the bio-based packaging reached only 18 % degradation. According to the modeling results, it is estimated that it will take about 2 years for the fragments of biodegradable bags to completely break down, provided the environmental conditions are stable.