Nano- and Microplastics in Single-Use Plastic Water Bottles: A Review of Occurrence, Health Risks, and Regulatory Needs

Nano- and microplastics (NMPs), which are ubiquitous environmental pollutants, are commonly found in single-use plastic water bottles. They originate primarily from the bottle material itself with the amount increasing through mechanical wear. This review synthesizes current scientific knowledge on the occurrence, health risks, and regulatory considerations concerning NMPs in single-use plastic water bottles. The review revealed that concentrations vary widely, leading to potential human exposure risks. Ingested NMPs can induce oxidative stress, inflammation, disruption of gut microbiota and potential bioaccumulation. Current health risk assessments are challenged by inconsistent methods and lack of standardized reference materials. While regulatory frameworks addressing NMP contamination are developing globally, they lack consistency and legally enforceable limits. Standardized detection and monitoring are emerging priorities, but legally enforceable limits and comprehensive policies are underdeveloped. This review highlights an urgent need for consistent regulations, standardized analysis methods, and research that examines realistic human exposure and toxicological impacts. To safeguard consumer health amidst escalating plastic utilization, it is essential for policymakers, researchers, industry, and public health stakeholders to coordinate their efforts to mitigate NMP contamination in single-use plastic water bottles.