1 What microplastics are (and why they end up on our plates)
Microplastics are plastic fragments smaller than 5 mm, originating from the degradation of larger plastic materials, or those intentionally manufactured in this size – as with the production of certain cosmetics3.
They can be found in the air, in drinking water, in packaged foods, in fish and shellfish. And yes, even in table salt and honey!
It is estimated that every adult ingests around 39,000 to 52,000 particles per year, equivalent to 5 grams of plastic – roughly the weight of a credit card.4
2 The intestine as a mirror of the environment
Among the most influential studies5 on this topic, that conducted by Professor Giovanni Marfella’s research group identified fragments of micro- and nanoplastics within the atheromatous plaques of patients undergoing vascular surgery. This is an important finding, confirming that these particles are capable of crossing intestinal barriers and spreading throughout the body.
3 But what happens when microplastics enter our bodies?
The gut is our main interface with the outside environment; it is where digestion takes place and nutrients are absorbed – processes essential for providing the energy needed to keep our bodies functioning efficiently. A recent study6 suggests a possible link with chronic asymptomatic inflammation – inflammatory states that persist over time, even in the absence of obvious infection or symptoms, which can progressively damage tissues in subtle, imperceptible ways, making them all the more concerning for our health.
4 Protective strategies: What can we do?
Further confirmation comes from recent experimental studies7 on water treatment. Among the methods analysed to reduce the presence of microplastics, coagulation techniques have proved effective, thanks to their ability to cause particles to clump together, making them easier to separate and remove.
In particular, chitosan – a natural polysaccharide derived from chitin (a molecule found in the exoskeletons of crustaceans) – has shown the ability to aggregate microplastics and promote their removal.
A recent laboratory study8 evaluated the effectiveness of chitosan in removing polyethylene particles from synthetic wastewater, analysing various parameters. The best results – with an 81.5% removal rate of microplastics – were obtained at pH 6.0 and a chitosan concentration of 100 mg/L. This molecule carries an electrical charge opposite to that of microplastics; when they meet, their charges neutralise and the particles aggregate, forming small clumps that are easier to remove.
This supports the notion that chitosan represents one of the most promising and sustainable strategies for reducing the build-up of microplastics – not only in the environment but also in the human body9.
As shown in a recent study10 dby Professor Umberto Cornelli, a single oral dose of 0.8 grams of fibre derived from Procambarus clarkii (PCC-chitosan) increased the excretion of microplastics in faeces by 45% compared with the control phase.
Beyond its quantitative efficacy, the study also revealed a selective action: chitosan bound to synthetic fibres such as polyethylene, polypropylene, rayon and PET, altering their shape and size and thereby promoting their elimination.
This approach opens a new frontier in managing exposure to microplastics – actively supporting their removal in a way compatible with human physiology and without any known side effects.
5 Our gut’s health today is also a reflection of the planet’s health.
Microplastics are no longer an “external” phenomenon, but a reality that “passes through” us. That is why every step towards greater awareness – in our diet, in our habits, in research – is also a step towards personal ecology.
