Microplastics in drinking water: A review on methods, occurrence, sources, and potential risks assessment

Microplastics in drinking water captured widespread attention following reports of widespread detection around the world. Concerns have been raised about the potential adverse effects of microplastics in drinking water on human health. Given the widespread interest in this research topic, there is an urgent need to compile existing data and assess current knowledge. This paper provides a systematic review of studies on microplastics in drinking water, their evidence, key findings, knowledge gaps, and research needs. The data collected showed that microplastics are widespread in drinking water, with wide variation in reported microplastic concentrations. Standardized methodologies are urgently needed. There were more fibrous and fragments microplastics, with the majority been <10 μm in size composed by polyester, polyethylene, polypropylene, and polystyrene. Little attention has been paid to the color of microplastics. More research is needed to better understand the occurrence and transfer of microplastics throughout the water supply chain and the treatment efficiency of drinking water treatment plants (DWTPs). Methods capable of analyzing microplastics <10 μm and nanoplastics are urgently needed. The potential ecological assessment model for microplastics currently in use needs to be improved to take into account the complexity and specificity of microplastics.