Environmental Fate, Toxicity, and Release Risks of Graphene‐Based Materials in Water Treatment Systems

ABSTRACT

Graphene‐based materials (GBMs), particularly graphene and graphene oxide (GO), have emerged as highly efficient adsorbents and membrane components for advanced water treatment owing to their exceptional surface area, tunable surface chemistry, and antimicrobial properties. However, the rapid development of graphene‐enabled technologies has outpaced understanding of their environmental, toxicological, and life‐cycle implications. This review critically synthesizes current knowledge on the synthesis, applications, environmental fate, toxicity, and sustainability of GBMs for water and wastewater treatment. Conventional and green synthesis routes for GO and reduced graphene oxide (rGO), together with recent advances in material stabilization, durability, and scale‐up, are briefly discussed to provide context for practical applications. We evaluate the toxicity of GBMs to aquatic microorganisms, invertebrates, fish, and humans, highlighting size‐ and oxidation state‐dependent effects, reactive oxygen species generation, membrane damage, inflammation, and emerging concentration thresholds for safety. Pathways of environmental release during manufacturing, operation, regeneration, and disposal are examined alongside their implications for sludge, soils, and receiving waters. LCA studies are reviewed across graphene synthesis, use, regeneration, and end‐of‐life management, emphasizing the absence of harmonized disposal guidelines. Regulatory gaps, including the lack of standardized nanotoxicity testing protocols and drinking‐water guidelines, are also discussed. Finally, we examine key challenges for large‐scale implementation and outline safe‐by‐design strategies, including greener synthesis, material immobilization, membrane stabilization, magnetic recovery, environmental monitoring, and integrated life‐cycle assessment. Overall, GBMs offer significant promise for next‐generation water purification, but their responsible deployment requires integrated risk assessment, standardized testing, and robust regulatory oversight throughout the material life cycle.