First study of its kind on the microplastic contamination of soft drinks, cold tea and energy drinks - Future research and environmental considerations

Abstract

Investigating wide range of food products of direct human consumption for microplastics is critical to understand the routes of contamination and assess the risks in microplastics uptake by humans. However, microplastics knowledge for many beverage products excluding beers is still lacking. Here, common beverages (n = 57; 27 brands) such as soft drinks (n = 19), energy drinks (n = 8), cold tea (n = 4) and beer (n = 26) were targeted for microplastics occurrences in Mexico and their shape, size, surface morphology and polymer composition were analyzed. Microplastics were detected in 48 out of 57 samples tested. The results identified microplastics of various forms (fibers and fragments) and sizes (0.1-3 mm) of colors (blue, red, brown, black and green), in amounts ranging from not detected to 28 ± 5.29 particles/L. Micro-Raman spectroscopy identified particles as polyamide, poly(ester-amide), acrylonitrile-butadiene-styrene and poly(ethylene-terephthalate) indicating microplastics contamination of synthetic textiles and packaging origin in the beverage products. Finally, this paper discusses that human excreta could act as a vehicle for the dispersion and accumulation of microplastics into terrestrial and aquatic environments. Combined, it is the first study to investigate microplastics contamination on soft drinks, energy drinks and cold tea and to document the material composition of microplastics from beverage products.

Keywords: Beverages; Human excreta; Mexico; Microplastics; Polyester; Wastewater.