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Micro-and nanoplastics (MNPs) are particles that are smaller than a millimeter in size and have infiltrated both terrestrial and aquatic ecosystems. MNPs pollution have become a widespread problem causing severe adverse effects on human health and the environment worldwide. Once in the environment, these polymers are not easily degradable due to their recalcitrant nature and small size and are easily consumed by aquatic organisms and transported through the food chain, at great risk to human health. Substantial evidence demonstrates the negative effects of MNPs residues on aquatic organisms' reproductive and developmental defects. Similarly, soil flora, soil quality, and plant height have been severely impacted by their presence in the agroecosystem. This is evident in the inhibition of water absorption by blocked seed pores, delayed germination, and the dramatic decline in transpiration rates and growth of plant roots, inevitably leading to drop in biomass and crop production, posing an overall threat to global food security. In this review, we present the impact of MNPs in agroecosystems around the globe, including their sources, occurrence, distribution, transport, and ultimate fate. We recommend using bio-based plastics, eco-friendly remediation strategies, reformed agricultural practices, non-single-use synthetic plastic legislation, and increased plastic waste disposal awareness campaigns as effective tools to mitigate this problem.

Although the use of plastics varies across different regions, Africa is ranked second after Asia as an indiscernible consumer of plastics that break down into microplastic. Moreover, little is known about the impact of these microplastics across the African continent. This review provides insight into what microplastics are and their impact on the environment across Africa. The mismanagement of plastic waste is at its peak in Africa, as the continent mismanages over 70% of daily generated waste on average through activities such as tourism, fishing, and waste transport from one end to the other through waterways. Regarding the impact of microplastics on the environment, we found that they facilitate severe environmental consequences, such as the development of metal toxicity within aquatic and terrestrial organisms, disruptions of the food chain in the ecosystem, and public health challenges to humans who consume seafood. Alternatively, bioplastics are promising biodegradable and environmentally friendly plastic materials that could be crucial in expanding Africa's plastic industry. Furthermore, the continent has some widely spread biobased renewable raw materials that can be harnessed for developing bioplastics. Therefore, biomass-based polymers are promising alternative plastic feedstocks for producing plastics because they can readily biodegrade and break down in industrial compost facilities.

Africa is a large continent ranked amongst the top consumer of plastic materials. However, the improper handling of plastic wastes has resulted in massive pollution of different aspects of the environment (water, soil, sediments, air, food, etc.) within and around the region. The fragmentation and biodegradation of the bulk plastic material into small-sized particles has given rise to microplastic and nanoplastics. Owing to their small sizes, ease of transport, and large surface area, they tend to wreak serious havoc in the environment. Nevertheless, the growing awareness of the pollution problems caused by micro/nanoplastic debris is instrumental towards circumventing its widespread across the ecosystem. This review provides a state-of-the-art information on the prevailing nanoplastic surge across the borders of Africa, the ineffective management policies of plastic wastes, potential environmental hazards, and possible remediation strategies. Additionally, prospective insights into new areas for advanced research were highlighted.

The prevalence of micro and nanoplastics (MNPs) across the various environments and their negative impact on ecosystems have become a serious global threat and are currently a subject of many environmental concerns. Studies have provided evidence that MNPs have the potential to leach toxic plastic chemical additives and can adsorb a variety of persistent organic environmental pollutants, thereby enhancing their bioavailability, toxicity, and dispersion. Moreover, these MNPs easily penetrate the food chain and might cause health problems when ingested by humans and other organisms. Currently, there is complexity in understanding the mechanisms by which these toxic chemicals adsorb/desorb onto/from MNPs, and the physical and biological impacts of these chemical additives. To date, there is a considerable lack of knowledge on the major chemical additives of concern used in the plastic industry, their fate once MNPs dispose into the environment, the factors that affect their degradation, and their consequent impacts on human health. This review critically analyzes the current knowledge concerning the physical, chemical, and biological impacts of MNPs, and the various chemical and organic pollutants associated with MNPs. Emphasis was laid on their types, occurrence, fate, and distribution in the environment. The different techniques used in their identification, characterization, and removal were also elucidated. Furthermore, the consequent harmful effects of MNPs on human health were discussed to spur more future studies and fill knowledge gaps in this area.