Genotoxicity assessment of polyethylene microplastics using zebrafish Danio rerio

Abstract

Rapid population expansion fosters the development of more industries. Nevertheless, these industrial operations have significantly accelerated the spread of plastics in the surrounding ecosystem. Plastic materials are versatile, resilient, and inexpensive. These favourable characteristics have made plastics the most widely used material, which has made them a menace. The global output of plastic materials has expanded in response to rising demand. However, the inappropriate usage and unmanaged littering of plastics have become a matter of environmental concern. newlineIn 2020, the COVID-19 pandemic significantly boosted plastic manufacturing and consumption. In addition, its timely decomposition results in the creation of microplastics, which pose a rising environmental danger. Polyethylene (PE) is the most extensively used plastic polymer. Despite the number of studies on its distribution and occurrence, there is no study reported on the deleterious effect of polyethylene microplastics (PEMPs). Therefore, the research presented in this thesis is based on the original research work carried out to search for the impact of microplastics on aquatic life and human beings using the most significant animal model, the zebrafish. newlineZebrafish (Danio rerio) has a completely sequenced genome that harbours orthologs of 70% of human genes, including 86% of known drug targets, thus facilitating the prediction of the toxicological impact on human beings. The data of the present research work revealed the dose-dependent response of polyethylene microplastics in zebrafish embryos. The genotoxicity assessment has identified the toxicological effect of polyethylene microplastics at the molecular level which is very significant from toxicological assessment point of view. newlineThe biochemical assessment results have indicated that polyethylene microplastics deliberately induce oxidative stress and can also disturb the antioxidant defence system in zebrafish embryos, which possess genetic and physiological similarities with human beings.