Food, water, and air

Microplastics have been reported across the things people eat, drink, and breathe. Reported concentrations vary by location, product, particle size, and detection method.

Seven microscope images of individual sub-micrometre particles, each paired with a spectrum matching a plastic standard — How a speck becomes a named polymer. Each panel is one particle imaged in bottled water, and each graph compares its measured spectrum (blue) with a reference standard (orange) for polyamide, polypropylene, polyethylene, PMMA, PVC, polystyrene, and PET. Most of these particles are under a micrometre—far below what visual counting can reach. Qian et al., PNAS (2024), Rapid single-particle chemical imaging of nanoplastics · CC BY 4.0

Drinking water

Well established

Studies have reported particles in both tap and bottled water. A simple bottled-versus-tap rule is not supported across every place and study because water sources, treatment, packaging, and analytical methods differ.

WHO review: Microplastics in drinking-water

Food and drinks

Emerging

Seafood: Shellfish eaten whole may include particles from the digestive tract; results vary by species and location.
Salt and staple foods: Particles have been reported in salt and other foods, but contamination control and identification quality vary.
Beverages: Studies include bottled water, beer, milk, tea, and other drinks, often with very different size thresholds.
Food-contact materials: Researchers study release from packaging and preparation. Release from an item is not always equal to the amount a person swallows.

Current food evidence: U.S. FDA

Indoor air and dust

Emerging

Textiles, furnishings, building materials, and outdoor air can contribute fibres and fragments indoors. Concentrations depend on the room, activity, ventilation, sampling duration, and the sizes a study can detect.

Scanning electron microscope image of a clump of household dust at micrometre scale — Microscopic household dust. This contextual image shows scale and complexity; not every visible particle is plastic. NIAID, Wikimedia Commons · CC BY 2.0

Why counts cannot be converted cleanly into mass

Well established

A particle count treats a tiny fibre and a much larger fragment as one particle each. Converting count into mass requires reliable size, shape, thickness, and polymer-density information that many studies do not provide.