Microplastic pollution has emerged as a critical environmental issue, extending beyond aquatic systems to significantly impact soil ecosystems and pose potential risks to human health. This research aims to analyze the global evolution of microplastic risk assessment research through a scientometric approach. Data was collected from the Scopus database using a structured search strategy, and analyzed using VOSviewer, Bibliometrix, and CiteSpace to identify publication trends, keyword co-occurrence networks, and thematic evolution. The results reveal a marked increase in research output since 2020, with a transition from early descriptive studies on microplastic occurrence (2013–2016) toward mechanistic and integrated risk assessment frameworks (2021–2025). Key research clusters include physicochemical processes such as adsorption and transport in porous media, soil accumulation and land-use impacts, microbial interactions analyzed through metagenomics, plant–microplastic interactions affecting crop productivity, and emerging concerns related to human health exposure. Furthermore, widely used indices such as Pollution Load Index Polymer Hazard Index and Potential Ecological Risk Index demonstrate variability in risk estimation, highlighting the lack of methodological standardization. Overall, the research concludes that microplastic risk assessment has evolved into a multidisciplinary and increasingly complex field, requiring the development of standardized, multi-compartment, and predictive frameworks to support environmental management and sustainability-oriented decision-making.