Investigating the Presence of Microplastics as an Emerging Contaminant in Water and Various Beverages: A Review Study

Introduction and purpose: Microplastics (MPs) have emerged as a pollutant in water and various types of beverages. Given that humans are regularly exposed to the risk of microplastic accumulation in the body through the consumption of water and different drinks, this review study aimed to assess the occurrence of this emerging pollutant across water and various beverage categories. Methods: For this review study, the articles on the presence of MPs in beverages published up to 2024 were thoroughly reviewed. These articles were identified through searches conducted in reputable national and international databases, including Google Scholar, PubMed, Embase, Science Direct, and SID. The search utilized both Persian and English keywords, such as microplastic, beverages, human health, tea, bottled water, tap water, and soft drinks. Results: The review examined the presence of microplastics in a range of beverage types, including bottled water (11 articles), tap water (6 articles), tea and coffee (7 articles), milk (6 articles), and energy drinks and sodas (4 articles). According to the results, the frequency of MPs in each liter of bottled water and tap water was between 4.6 and 20348 particles, and their dominant sources were polypropylene and polyethylene terephthalate. The size range of MPS in tea varied from 200.6-220.7 µm, and the common polymers identified were ethylene-vinyl acetate and acrylonitrile butadiene styrene. Furthermore, the average number of MPs in milk samples was 6±5 particles per liter. The results pointed out that the possibility of milk being contaminated by MPs during the production process was higher than during the packaging process. Conclusion: As evidenced by the obtained results, MPs were present in all the beverages studied, and the sources of their contamination included the packaging of bottles and abrasion of bottle caps in bottled water, water treatment and pipelines in tap water, agricultural plastic films, and the use of plastic packaging in tea and milk. The presence of MPs in water and beverages has adverse effects on human health, and there is a need for further studies and new standards to control the related risks.