Microplastics in bottled water: assessing drinking safety in Nepal

ABSTRACT Microplastics in bottled drinking water pose several potential health risks. Therefore, the objective of this study was to quantify the microplastic content and determine their types in bottled drinking water in Nepal. Bottled water samples of 17 different brands representing five provinces of Nepal were collected based on random sampling and availability. The methodology involved separating microplastics from bottled water using vacuum filtration, quantifying their mass, and conducting microscopic imaging to identify their types – such as fibers, beads, fragments, and films. Microplastics identification was further confirmed using the hot needle test. All 17 bottled water brands were found to contain microplastics. The microplastic content in the samples ranged from 0.09 ± 0.04 to 8.40 ± 4.94 mg/L. Smaller microplastics (<100 μm) predominated, comprising 70–98% of the total, while larger particles (100–5,000 μm) accounted for only 2–30%. The composition of microplastics across samples was as follows: microfibers (2–29%), microbeads (4–59%), microfilms (1–13%), and microfragments (24–80%). The findings of this research provide valuable insights into the prevalence of microplastics in bottled drinking water in Nepal and highlight the need for stricter regulations mandating microplastic testing and continuous monitoring.