Microplastics have been detected in a variety of foods and beverages, including in fish (FPF reported), seafood (FPF reported), salts (FPF reported), honey, beer (FPF reported), and bottled water (FPF reported). The normal and intended use of food packaging and other food contact articles (FCAs) is a source of this contamination (FPF reported) but few studies have compared microplastic levels across several types of FCAs. In an article published on May 8, 2025, in the Journal of Food Composition and Analysis, the French Agency for Food, Environmental and Occupational Health and Safety (ANSES), examined microplastic concentrations in different types of beverages available on the French market with their main FCA made of plastic, glass, metal, beverage cartons (brick), or bag-in-box (cubitainers).
Iseline Chaïb and co-authors detected microplastics across all types of beverages but at different concentrations, ranging from 2.9 ± 0.7 particles/L in waters to 8.2 ± 3.3 particles/L in wines, 28.5 ± 13.1 particles/L in teas, 31.4 ±16 particles/L in colas, 45.2 ± 21.4 in lemonades, and 82.9 ± 13.9 in beers. The most prevalent polymer types were polyesters, polyolefins, and cellulose, but many MNP polymer types could not be identified at all.
The study provided microplastic concentrations as particles/L, and using that metric the authors reported that the levels of certain microplastics changed with the food contact material. Specifically, they pointed out that polyester particles were more abundant in glass-packaged soda and beer than in the plastic-packaged equivalent. The polyolefins particles/L were highest in teas in glass bottles, while cellulose particles/L were most abundant in brick-packaged wine, followed by canned lemonade. Cans and glass further contained the highest number of microplastics per liter, with unknown polymer types.
The study further shows that microplastic concentrations vary (strongly) within a certain packaging type and even within food contact articles of the same batch, indicating that microplastic release also depends on the individual product, its production process, and filling lines. This is in line with other studies, for instance, some have detected more particles in plastic bottles while ANSES reports more in some glass bottles.
Importantly, micro- (and nano)plastic detection is not standardized, which is why inter-study comparisons are difficult. For instance, with the method Chaïb and co-authors used, they could detect particles down to 30 µm. This means they neglected particles of smaller sizes, which might still be present in their samples and be detected by other methods/studies.
Chaïb and co-authors hypothesized that polyester particles present in one of the tested soft drink brand’s glass bottles originated from the paint on the outside of their metal caps. To test their hypothesis, they tested whether cleaning the caps reduces microplastic contamination. Blowing the caps with air and then rinsing them with water and 79% ethanol before capping reduced contamination significantly from 287.3 ±81.4 particles/L to 86.7 ± 42.3 particles/L. Furthermore, they identified scratches on the outside of the caps and the lid’s outside paint on their inside. The authors concluded that “microplastics originate from the exterior paint of capsules,” based on their analysis for the one brand tested, and highlighted that “a cleaning step before encapsulation can significantly reduce beverage’ contaminations.”
The scientists bought the samples from retailers in France in June 2023 and assessed six samples of each type. Samples differed in beverage type (i.e., water, cola, tea, lemonade, beer, and wine) and volume (0.33 – 3 L) as well as packaging materials (i.e., plastic, glass, metal, brick, or cubitainers). In case beverages contained carbon dioxide, they were degassed before further treatment. The whole sample volume was filtered over glass fiber filters and using a stereomicroscope, the number, shape, and color of particles were assessed. Fourier Transform Infrared Spectroscopy (FTIR) was used to determine the particles’ polymer types. Sizes from 30 to 500 µm were considered.
Reference
Chaïb, I. et al. (2025). “Microplastic contaminations in a set of beverages sold in France.” Journal of Food Composition and Analysis. DOI: 10.1016/j.jfca.2025.107719
