Researchers at the University of Plymouth have discovered that nanoplastic particles can infiltrate and accumulate in the edible parts of vegetables, posing new questions about food safety and environmental impact.
Plastic pollution is a well-documented global crisis, fragmenting into microplastics and nanoplastics that infiltrate various ecosystems. Adding to growing concerns, a new study from the University of Plymouth has uncovered that these microscopic particles can accumulate in the edible parts of vegetables, potentially posing risks to both human and animal health.
The research, published in the journal Environmental Research, is the first to demonstrate that nanoplastics — some as tiny as one millionth of a centimeter — can be absorbed into the roots of crops and spread to the parts we eat.
Utilizing radishes in a controlled hydroponic system, the scientists exposed the plants to a solution containing radiolabeled polystyrene nanoparticles.
After five days, they found that nearly 5% of these particles were retained by the root system, with millions of nanoplastics infiltrating the crop.
Of those, roughly 25% migrated into the edible fleshy roots, while 10% accumulated in the leaves.
“Plants have a layer within their roots called the Casparian strip, which should act as a form of filter against particles, many of which can be harmful,” lead author Nathaniel Clark, a lecturer in physiology at the University of Plymouth, said in a press release. “This is the first time a study has demonstrated nanoplastic particles could get beyond that barrier, with the potential for them to accumulate within plants and be passed on to anything that consumes them. There is no reason to believe this is unique to this vegetable, with the clear possibility that nanoplastics are being absorbed into various types of produce being grown all over the world.”
The study marks a notable advancement in understanding the movement of nanoplastics through the food chain, building on previous research by the team which showed the rapid uptake of plastic nanoparticles by mollusks and fish.
This investigation revealed that these tiny pollutants could indeed penetrate and accumulate within plants.
“To some extent, these findings shouldn’t be a surprise — after all, in all our previous work we have found microplastic pollution everywhere we have looked for it. However, this study provides clear evidence that particles in the environment can accumulate not only in seafood but also in vegetables,” added senior author Richard Thompson, the director of the International Marine Litter Research Unit at the University of Plymouth. “This work forms part of our growing understanding on accumulation, and the potentially harmful effects of micro- and nanoparticles on human health.”
While these findings underscore a need for further exploration into the impacts of nanoplastics on environmental and human health, this study provides crucial evidence of how pervasive plastic pollution can be, potentially making its way onto our plates.
Source: University of Plymouth