The Occurrence and Fate of Microplastics in Wastewater Treatment Plants in South Africa and the Degradation of Microplastics in Aquatic Environments—A Critical Review

Abstract

The occurrence of microplastics (MPs) and their omnipresence have attracted enormous attention across the globe; however, research on MPs in South Africa is still in its infancy and thus, the data are still very much lacking. Approximately 120 million tons of general waste is generated each year in South Africa, which exacerbates the pressure on the ability of municipalities to manage waste. Wastewater treatment plants (WWTPs) are at the center of this general waste that includes plastic debris and primary MPs that are discharged from households and industries. In general, the removal efficiency of MPs across the globe was found to be between 70% and 99%, with biological treatment technology common in both primary and secondary treatment steps in WWTPs. Furthermore, the current review paper has revealed that there is a wide research gap on the occurrence and fate of MPs in WWTPs across South Africa. This is a worrying factor considering the increasing rate of plastic waste generation due to rapid industrialization, urbanization, and overpopulation in the country. More so, the scarcity of data regarding the occurrence of MPs in freshwater is widely noticeable across the country. Therefore, given the amounts of MPs discharged from households, industries, and plastic debris littered into the surface waters, the data on the occurrence and fate of MPs in South Africa should be given the urgent attention they deserve. To achieve the effective and sustainable management of water resources and services set out in the National Development Plan (NDP) 2030 adopted by the government, the status and capabilities of WWTPs to remove MPs must be monitored and addressed. In addition to achieving the zero waste to landfill goal by 2030, a circular economy is regarded as the most effective model for solving the plastic waste crisis in the environment; therefore, its full implementation is required for a substantial impact.