The large-scale manufacturing, extensive use, ineffective management, and improper disposal of plastics and plastic-containing products have made them one of the most significant environmental concerns of today. The transport of micro and nano plastics (MNPs) between terrestrial and freshwater environmental compartments, including reciprocal contributions and inherent connections, and the effects of MNPs on the primary producers in various ecosystems, are two pertinent research areas. Herein, we provide a critical overview of the accumulation of MNPs by primary producers in the freshwater and terrestrial biota. On the one hand, we examined the occurrence of MNPs and their effects on freshwater species in natural systems, and laboratory-based ecotoxicological effects of ingesting MNPs. On the other hand, MNP distribution in the soil environment, root uptake processes, and mode of action, still largely unknown, were assessed to highlight terrestrial ramifications. To this end, the presence, phytotoxicity, distribution, absorption, and function of MNPs in different soil types were examined. This review also discussed the potential for remediating MNPs in soil via the formation of eco-corona, and how eco-corona formation aids in lowering MNP toxicity in freshwater algae and terrestrial plants.