Are the Same Type of Microplastics Found in Alcoholic and Non-Alcoholic Beverages?

A recent study published in Environmental Pollution dives into the South African beverage market, analyzing microplastic contamination in alcoholic and non-alcoholic beverages sold in the country (1). This study, led by Dalia Saad from the University of the Witwatersrand and the University of Pretoria, underscores the threat that microplastics have in the beverage industry. It also highlights the pervasive presence of microplastics in beverages packaged in glass, aluminum, and polyethylene terephthalate (PET), which has both health and environmental implications.

What are microplastics?

Microplastics are tiny plastic particles less than 5 mm in size. Because of their size, they are often difficult to see in the environment and in consumer products (2,3). However, thanks to increased industrial practices and plastic production, more microplastics are being detected in virtually every environmental and consumer medium, from bottled water to food products (2,3). This trend poses a huge problem for living organisms, because these plastic particles could negatively impact them in several ways.

What did the researchers do in their study?

In their study, the research team examined this broader issue by specifically analyzed South African beverages as the representative sample. The idea was to see whether the level of microplastic contamination was different based on the type of beverage and the packaging it was in. This study also looked at the types and the characteristics of the microplastics found in these beverages (1).

After filtering and digesting the beverage samples, the researchers stained them with Rose Bengal dye to improve visualization of the plastic particles. The samples were then examined under a stereomicroscope for physical characterization and analyzed using micro-Raman spectroscopy for chemical composition (1). This dual approach allowed the team to differentiate between shapes such as fibers and fragments, determine size ranges, and identify specific polymer types (1).

What did the study’s findings reveal?

The study’s findings revealed a consistent presence of microplastics across all tested beverage types. The mean MP concentration in non-alcoholic beverages was found to be 9.5 ± 8.5 particles per liter, while alcoholic beverages contained slightly higher levels at 15 ± 7.6 particles per liter (1). From a statistical perspective, there were no significant differences between packaging types, such as glass versus aluminum for alcoholic beverages or PET versus aluminum for non-alcoholic ones (1).

What were the correlations with fiber sizes?

An aspect to this study was that the researchers observed that fibers were most prevalent in alcoholic beverages packaged in glass and in both PET and aluminum-packaged non-alcoholic drinks (1). On the other hand, fragments were more common in alcoholic beverages packaged in aluminum, indicating potential shedding or contamination during the production and packaging process (1). Across all beverage types, the mean size of microplastic particles was less than 1 mm, with black, blue, and green particles being the most abundant in color (1).

Multivariate principal component analysis (PCA) and Pearson correlation coefficient matrices helped illuminate the notable correlations between fiber sizes in both beverage categories. For non-alcoholic beverages, strong positive correlations were observed between fiber size ranges of 0.02–0.1 mm and 0.1–0.5 mm, while in alcoholic beverages, the correlations occurred between larger fiber size ranges of 1–2 mm and 2–3 mm (1). These findings indicate that microplastics of various sizes are distributed broadly across different beverage types, suggesting multiple potential sources of contamination during manufacturing, storage, and packaging (1).

The researchers also found that there were six polymer types in their beverage samples. These included polypropylene (PP), polyethylene (PE), polyurethane (PU), polyamide (PA), polyethylene terephthalate (PET), and polybutylene terephthalate (PBT). What these polymers have in common is that they are commonly used in consumer packaging, industrial coatings, and manufacturing materials (1). As a result, it suggests that the packaging and processing stages as the likely contributors to microplastic contamination (1).

The authors emphasized that while the detected levels might seem modest, the study’s significance lies in its comprehensive approach and its potential to inform national policy and sustainability strategies.

“This study offers a holistic appraisal of MPs in commercially sold beverages in South Africa. It establishes a framework for assessing the socioeconomic impacts of MPs, including their commercial, environmental, social, and sustainability implications,” the authors wrote in their study (1).

References

1. Ramaremisa, G.; Erasmus, R. M.; Tutu, H.; Saad, D. Occurrence and characteristics of microplastics in South African beverages. Environ. Pollut. 2025, 365, 125388. DOI: 10.1016/j.envpol.2024.125388
2. Wetzel, W. Quantifying Microplastics and Anthropogenic Particles in Marine and Aquatic Environments. Spectroscopy. Available at: https://www.spectroscopyonline.com/view/quantifying-microplastics-and-anthropogenic-particles-in-marine-and-aquatic-environments (accessed 2025-11-10).
3. Workman, Jr., J. How Colorants Complicate Raman Spectroscopy of Microplastics: New Insights from Environmental Research. Spectroscopy. Available at: https://www.spectroscopyonline.com/view/how-colorants-complicate-raman-spectroscopy-of-microplastics-new-insights-from-environmental-research (accessed 2025-11-10).