Evolution of Microplastics Released from Tea Bags into Water

Aging and particle dynamics from cut pieces of nylon, polypropylene, and cellulose tea-bag materials in water.

Source details

Alexander A. Yaroslavov, Anna A. Efimova, Tatyana E. Grokhovskaya, Anastasiia G. Badikova, Vasily V. Spiridonov, Denis V. Pozdyshev, Sergey V. Lyulin, Jose M. Kenny. Polymers. 2025.

DOI: 10.3390/polym17192700

Findings

Bulk chemistry identified nylon, polypropylene, and cellulose bag materials. Particle sizes and concentrations evolved differently during soaking and subsequent aging. Cellulose-derived particles must remain separate from synthetic-plastic particles.

Methods and scope

Infrared spectroscopy, calorimetry, and thermogravimetry identified bulk materials. DLS followed hydrodynamic size; NTA measured suspended-particle concentration; laser electrophoresis measured mobility. Cut and rinsed bag squares were exposed in water under short and extended soaking/aging protocols. Distilled-water DLS control showed no scattering correlation. Experiments were replicated.

What this source can support

Useful mechanistic evidence that time, material, and size methodology affect observed particles, particularly below ordinary microscopy windows.

Cut squares rather than intact retail bags. Some measurements followed prolonged heating/aging, not a normal cup preparation. Bulk polymer identity does not chemically identify every NTA-counted particle. Numerical NTA table resides in a supplement not reviewed here, so no exact count is reproduced. In-vitro findings do not establish consumer safety or clinical harm.

Related evidence

Tea bags