A review of microplastics pollution and its remediation methods: Current scenario and future aspects

Global plastic production and its use have been omnipresent since the early 19th century. The disposal of plastics undergoes breakdown due to various physicochemical and biological factors that trigger the formation of microplastics (MPs). Due to their hydrophobic properties, structural stability, and functional groups, it is difficult to degrade in natural habitat. The presence of their large surface area also helps to resist the decay of MPs. This review summarizes the recent trends and development of MPs degradation. The method includes biodegradation, various types of advanced oxidation processes (AOPs) such as photocatalytic oxidation, photo-degradation, and electrochemical oxidation, and also discussed the potential health risk factors of MPs and their degradation products. Most of the methods achieved nearly satisfactory performance that degraded the MPs into CO2, H20, and also secondary microplastic particles with persistent organic pollutants (POPs) under laboratory conditions, which have been studied by various researchers. It is also evident that the degradation of MPs has many challenges, therefore finding a sustainable approach is an urgent need to deal with the issue of global microplastic pollution. Some suggestions have been highlighted such as toxicity detection of remaining MPs particles after degradation, and analysis of secondary metabolites of microbes secreted during bioremediation that may have a negative impact on the environment. The selective and specific implementation of microbes and photo-catalyst that degrade MPs into useful and nontoxic components.