Branded milks - Are they immune from microplastics contamination?

Area of Science:

• Environmental Science
• Food Science
• Analytical Chemistry

Background:

• Microplastic contamination is increasingly recognized in the human food chain.
• Assessing microplastic levels in diverse consumer products is crucial for mitigation.
• Dairy milk products have not been previously studied for microplastic contamination.

Purpose of the Study:

• To investigate the occurrence and characteristics of microplastics in Mexican dairy milk.
• To establish a baseline for microplastic contamination in milk.
• To identify potential sources of microplastics in milk.

Main Methods:

• Collection and analysis of 23 milk samples from various brands in Mexico.
• Quantification of microplastic particles per liter.
• Characterization of microplastic particles by color, shape, and size.
• Identification of polymer types using Micro-Raman spectroscopy.

Main Results:

• Microplastics were ubiquitously detected in all analyzed milk samples.
• Concentrations ranged from 3 ± 2 to 11 ± 3.54 particles/L, with an average of 6.5 ± 2.3 particles/L.
• Predominant microplastics were blue fibers (<0.5 mm); identified polymers included polyethersulfone and polysulfone, commonly used in dairy processing membranes.

Conclusions:

• Dairy milk in Mexico is contaminated with microplastics.
• The identified polymers suggest dairy processing equipment as a likely source.
• Findings provide a baseline for future research and inform preventive measures in the dairy industry.