Branded milks - Are they immune from microplastics contamination?

The widespread dispersal of microplastic (plastic particle <5 mm) contamination in human food chain is gaining more attention in the public arena and scientific community. Better assessment of diversified consumer products is a key for combating problems related to microplastic contamination. To the best of our knowledge, no study has been conducted on dairy milk products, and the current research status of microplastics is lacking. Here, a total of 23 milk samples (22 adult and 1 kid) from 5 international and 3 national brands of Mexico was collected and tested for the occurrence of microplastics. Results confirmed the ubiquity of microplastics in the analyzed samples and showed variability ranging between 3 ± 2-11 ± 3.54 particles L-1 with an overall average of 6.5 ± 2.3 particles L-1 which are lower than any reported levels in liquid food products. Microplastic particles exhibited variety of colors (blue, brown, red and pink), shapes (fibers and fragments) and sizes (0.1-5 mm). Among which, blue colored fibers (<0.5 mm) were predominant. Micro-Raman identification results revealed that thermoplastic sulfone polymers (polyethersulfone and polysulfone) were common types of microplastics in milk samples, which are highly used membrane materials in dairy processes. Thus, this study findings developed a baseline outlook for microplastics contamination in dairy products and posed a great deal to take necessary controls and preventive measures to avoid them.