Long perceived as an environmental problem confined to beaches or the seabed, plastic fragments are now proving to be much more invasive. They enter our daily lives in unsuspected ways, even altering the very composition of the foods we consume. A recent study challenges our benchmarks by demonstrating a widespread presence of microplastics in milk and cheese, two pillars of the common diet.
Throughout the studies, an observation emerges. Human exposure to these particles is continuous. In 2022, researchers have shown that it can be found in the blood and in the lungs. Other recent work has observed their accumulation in the liver and heart, particularly in animals – and more recently in humans, which raises fears of long-term inflammatory effects. Dairy products now join this growing list of contaminated foods.
What the Italian study reveals about microplastics in milk and cheese
Researchers from the University of Padua have conducted one of the most rigorous analyzes to date of dairy contamination. Their study, published in the journal NPJ Science of Food in October 2025, involved 28 commercially purchased samples, including milk, fresh cheeses and aged cheeses. All stages of preparation were carried out in a clean room to avoid any external pollution.
The results were striking. Plastic particles were detected in 26 out of 28 samples. On average, researchers found around 350 particles per kilogram in milk, 1,280 in fresh cheeses and up to 1,857 in mature cheeses. This marked difference is explained by the cheese manufacturing process, which concentrates solid materials and multiplies the stages of contact with plastic surfaces (molds, packaging films, storage containers).
The plastics found most often belong to three main families. First we find PET, present in bottles and food containers. Then, polyethylene, common in bags and packaging films. Finally, polypropylene, used in particular for caps and rigid containers. Furthermore, the study reveals a majority of gray particles, generally resulting from the wear of industrial plastics. Food & Wine, which relays this data, reports a similar presence of microplastics in dairy products, fish and even bottled drinks.
For researchers, these particles do not come directly from raw milk, but slip throughout the production chain. Plastic equipment, protective clothing or packaging represent all possible sources of contamination. The more a product is processed, the more microplastics it accumulates.
A health issue that is still poorly understood but worrying
The presence of microplastics in food does not automatically mean immediate danger, but it opens up a worrying gray area. Scientists still lack precise data on how these particles interact with the human body. We already know that they can cross certain biological barriers, lodge in tissues and generate an inflammatory response. Research has also highlighted a possible link between chronic exposure and cardiovascular disorders, or impaired liver function.
Long-term effects likely depend on the size, shape and chemical composition of the particles. The finest fragments, sometimes less than 50 micrometers, are likely to circulate in the blood and penetrate the organs. The problem is therefore less visible than structural. It is part of a diffuse, slow, but persistent contamination.
The Italian study reminds us that dairy products are only one link in a much larger phenomenon. The food industry still relies heavily on plastic, from processing to packaging. Limiting this exposure requires rethinking the materials used, monitoring production, but also raising consumer awareness of the impact of packaging on their food. Behind a simple slice of cheese lies a major public health and ecological transition issue, which research is only just beginning to measure.
With an unwavering passion for local news, Christopher leads our editorial team with integrity and dedication. With over 20 years’ experience, he is the backbone of Wouldsayso, ensuring that we stay true to our mission to inform.
