Plastic pollution has become one of the most urgent global environmental challenges, with synthetic polymer production continuing to increase at an unprecedented rate. Recent estimates project that plastic production will approach 590 million tons annually by 2050, introducing vast amounts of waste into ecosystems worldwide. As plastics persist and degrade in the environment, they fragment into microplastics (MPs), particles less than 5 mm in size, which are now pervasive in marine, terrestrial, freshwater, and atmospheric systems. Of particular concern are microplastics' integration into global food webs, raising significant ecological and health-related questions. Notably, the enduring presence of MPs has fueled debate about their role as “techno-fossils”, signifying humanity’s impact on the geological record and the definition of the Anthropocene epoch. Despite growing research, two essential gaps remain: our understanding of microplastics’ full environmental dispersal mechanisms, and their formal recognition and significance within the Earth’s stratigraphic record as persistent, novel materials.

Clear gaps exist in comprehensively tracking microplastics from their numerous global sources through their diverse environmental pathways and endpoints. Furthermore, while the unique persistence and material properties of synthetic polymers suggest their potential as long-lasting geologic markers, the criteria for establishing MPs as reliable, formal stratigraphic indicators of the Anthropocene are not fully met. Recent studies highlight microplastics’ ubiquity, persistence, and unique composition, but more work is needed to link their environmental fate with their geological imprint. Addressing these gaps requires a cross-disciplinary approach that incorporates environmental science, sedimentology, geochemistry, and policy perspectives.

This Research Topic aims to clarify the dual environmental and geological legacy of microplastics, explicitly addressing their roles as both widespread pollutants and potential stratigraphic markers for the Anthropocene. The core objectives are to consolidate and advance knowledge on the global sources, dispersal, and sinks of MPs; critically evaluate their characteristics as novel, persistent materials; and examine the robustness of microplastics as chronological markers within the sedimentary record. By fostering a dialogue between environmental science and geology, this Research Topic seeks to clarify whether microplastics can serve as definitive “techno-fossils” and to inform policy, remediation, and scientific classification efforts.

This Research Topic is limited to works that advance understanding of microplastics' global dispersion, environmental persistence, and potential for recognition in the formal geological record of the Anthropocene. To gather further insights in this multidisciplinary arena, we welcome articles addressing, but not limited to, the following themes:

• Global environmental distribution, sources, and pathways of microplastics across ecosystems and the atmosphere

•Critical assessment of microplastics' novelty, persistence, and synchronicity as “techno-fossils” in sediments

• Analysis of microplastic polymer composition in sedimentary cores for stratigraphic dating and delineating the Anthropocene onset

• Environmental transformation processes affecting microplastics, including oxidation, irradiation, and fragmentation into micro- and nanoplastics

• Methodological advancements in the detection, quantification, and classification of MPs in geological and environmental matrices

We invite submissions of Original Research Articles, Comprehensive Review Articles, and Methodology Papers relevant to the detection, analysis, and interpretation of microplastics within the context of this Research Topic.

Are you interested in contributing a manuscript to this Research Topic?

Microplastics as Techno-fossils: Environmental Spread and Stratigraphic Significance in Anthropocene