Micro- and Nanoplastics in the Environment: Analytical Approaches, Environmental Fate, Life Cycle, and Remediation Strategies—A Scoping Review

Microplastics have emerged as one of the most widespread and significant environmental pollutants, occurring in aquatic and terrestrial ecosystems, the atmosphere, food, and living organisms. Given the rapid expansion of research in this field, a comprehensive synthesis of the current state of knowledge is warranted. The aim of this study was to map the available literature on microplastics, with particular emphasis on advanced identification and characterisation techniques, environmental transport and transformation processes, life cycle assessment, and remediation strategies. This scoping review was conducted in accordance with the PRISMA-ScR guidelines using publications retrieved from the PubMed, Scopus, Web of Science, and Google Scholar databases. The analysis demonstrated substantial advances in analytical methodologies, particularly spectroscopic and microscopic techniques, enabling the accurate characterisation of micro- and nanoplastic particles. It also highlighted the complex mechanisms governing the transport and transformation of microplastics across environmental compartments, as well as their important role as vectors of chemical contaminants. From a systems perspective, life cycle assessment of plastics was identified as an essential tool for evaluating their environmental impacts. Current mitigation approaches, including filtration technologies, wastewater treatment processes, and biological remediation strategies, were also reviewed, along with their limitations and potential for future development. This review identifies the lack of standardised analytical methodologies and the limited capability for nanoplastics detection as two major challenges hindering the global harmonisation of microplastics research. The findings emphasise the need for further interdisciplinary studies and the implementation of integrated strategies encompassing the entire life cycle of plastics to effectively reduce microplastics emissions and mitigate their environmental impacts.