For years the presence of micro and nanoplastics in the oceans has attracted the attention of scientists and public opinion. Much less explored, however, was the ability of agricultural crops to absorb these invisible but very pervasive particles.
A recent study, published on Environmental Research and conducted by a team led by Nathaniel J. Clark, he showed for the first time that the radishes (Raphanus Sativus) can absorb polystyrene nanoplastics within their tissues. A discovery that invites us to look carefully to the food we put on the table and the delicate balance between agriculture and environmental contamination.
To conduct the study, scientists have adopted an innovative approach, using nanoplastics of polistirene marked with carbon-14 (14c), a radioactive isotope that acts as a “label” allowing to precisely track down the particles inside the plant.
The radishes were grown in hydroponical systems for five days, exposing only the non -fleshy roots to the particles. In this way the risk of surface contamination was avoided and the path of the nanoplastics was clearly observed, from the root to the internal and edible tissues.
The results of the study
The results left little doubts:
In other words, the nanoplastics are not confined to the thin roots, but they manage to overcome the Caspry band, the natural barrier that normally filters unwanted substances, and reach the internal and edible fabrics of the plant, precisely the fleshy root we eat.
This discovery opens worrying scenarios. If the radishes are able to accumulate nanoplastics within a few days, it is plausible that other vegetables – consumed daily – can behave in the same way. The chronic man of man through the diet therefore becomes a concrete possibility.
At the moment we do not yet know with certainty what the effects of the nanoplastics on human health are, but preliminary studies suggest potential damage to cellular level, oxidative stress and inflammation.
The authors point out that the concentrations used in the study were superior to those presumably present in nature, a choice necessary to overcome the technical limits of the detection. However, the test of principle remains: the plants are able to absorb and move the nanoplastics into their edible tissues.
The next step will be to expand the research to other crops and other types of polymers, to understand if the phenomenon concerns only the polystyrene or even more widespread plastics such as polyethylene and PVC.
The study, however, highlights a silent danger already present in our diet: nanoplastics, so far associated above all with the oceans, can also contaminate common vegetables such as radishes. A scientific challenge that requires further investigations and more effective policies to reduce the dispersion of plastics in the environment.
