Occurrence of Microplastics in Tap and Bottled Water: Current Knowledge.
Level 5 - mechanism / opinion, no new human data
Oxford Level 5: narrative review without systematic search or meta-analysis
PubMed 35564678 · doi:10.3390/ijerph19095283
What was done
A narrative review was conducted across 21 studies to evaluate the presence, concentration, and packaging-related differences of microplastics in tap water and bottled water.
What was found
The abstract reports no numerical values or pooled metrics. Across the 21 reviewed studies, microplastics were detected in both tap and bottled water. Microplastic concentrations increased with decreasing particle size and were generally higher in bottled water than tap water. Among bottled waters, reusable PET and glass bottles showed higher contamination than other packaging types. Tap water had lower concentrations than raw natural water sources, indicating filtration efficiency in treatment plants.
Why it matters
This review synthesizes current evidence on drinking water as an ingestion pathway for microplastics, suggesting that tap water may result in lower exposure than bottled water.
Limits
The paper is a non-systematic narrative review of a small number of studies (n = 21). The abstract notes high inter-study variability that prevents quantitative comparisons or firm human health risk estimations. No clinical or toxicological endpoints were directly measured.
Cited by
- context Studies have found higher concentrations of microplastics in glass bottled water than in plastic bottled water due to plastic polymers in bottle cap paint shedding into the water.
- supports Studies in France and the US showed a larger volume and count of microplastics in glass bottled water compared to plastic bottled water due to paint on the metal lids.