Microplastics, defined as synthetic polymer particles measuring less than 5 mm in diameter, have emerged as a widespread and persistent contaminant in drinking water systems worldwide, entering through polluted source waters, wastewater discharge, and degradation of plastic distribution pipelines, atmospheric deposition, and packaging materials such as PET bottles. This review presents an integrated analytical and environmental chemistry perspective on the occurrence, sources, and polymer characteristics of microplastics in drinking water, with particular emphasis on the analytical techniques used for their detection and quantification, including Fourier Transform Infrared Spectroscopy (FTIR), Raman spectroscopy, Scanning Electron Microscopy coupled with Energy Dispersive X-ray Spectroscopy (SEM-EDS), and Pyrolysis-Gas Chromatography/Mass Spectrometry (Py-GC/MS). 

The study further examines the effectiveness of conventional and advanced drinking water treatment processes in removing microplastic particles, and synthesizes existing toxicological literature to assess the potential human health risks associated with microplastic ingestion through drinking water. Given the scarcity of region-specific investigations, the review also compiles and compares available Indian data alongside global findings to identify existing research gaps and propose meaningful directions for future study. 

The objectives of this review are to summarize the major sources and pathways through which microplastics enter drinking water supply systems; to compare the existing analytical and detection methods employed to identify and quantify microplastics in water, including microscopy, spectroscopy, and thermal analysis techniques; to evaluate the effectiveness of current water treatment technologies such as coagulation, filtration, and disinfection in removing microplastic contamination; to assess the potential human health risks associated with microplastic ingestion through drinking water based on existing toxicological evidence; and to identify key research gaps while proposing directions for future study, including a comparative analysis of regional and Indian data on microplastic contamination.