Microplastics Measurements in Cow Milk: Extraction and Characterization Methodologies

Microplastic (MP) pollution is a growing concern that affects habitats and species, contaminating all matrices. Additionally, plastic additives and chemical pollutants linked to MPs may have toxic effects on species. Currently, only few studies investigating the presence of MPs in farmed animals and their products, and research about the transmission of MPs from livestock products to humans is just at the early stage. Different studies have shown that MPs can accumulate in the digestive systems of some animals, causing inflammation, stress, and possible disruptions in nutrient absorption. MPs have been found in milk, meat, and other animal-derived products, raising food safety concerns. Therefore, scientists emphasize the need for further research to assess the risks. MP contamination in milk were detected in raw and processed milk, likely originating from contaminated feed, water, and plastic packaging. Livestock can ingest MPs through contaminated feed and water leading to potential health implications for animals and human consumers. Additionally, processing equipment and plastic containers may contribute to further contamination. The aim of this study is to find a valid method for MPs separation and characterisation in milk, following the product from milking to packaging to mitigate the impact of MPs in livestock farming. Milk samples were collected from farm to supermarket, observing different problematics depending on the fat presence, especially in raw milk. Major problematics regarded the milk filtration, due to the presence of fats. Heating the milk at different temperatures and the use of KOH 10% can partially solve these problems, helping in milk filtra-tion. Different filters were tested too, highlighting the need of high porosity for raw milk. Both microscopic and spectro-scopic techniques can be useful to count and characterize MPs on filter. The use of UV light can help in MP identifica-tion, especially for small and clear particles. Blank samples and the filtration of chemicals and distilled water used is essential to avoid MP contamination during all step, from sampling to microscopic and spectroscopic analysis. Further studies are necessary to assess the full impact of MPs in milk and potential risks to consumers. Addressing MP contamination in livestock farming is crucial for protecting both animal and human health. Collaborative efforts between policymakers, researchers, and farmers are necessary for developing sustainable solutions, and reduce plastic in agriculture and food production.