Plastic pollution has spread everywhere from deep oceans to mountain peaks. And now, scientists have found evidence it can also reach the vegetables we eat.
Researchers at the University of Plymouth report that nanoplastics, some as small as a millionth of a centimeter, can move from soil or water into plants. In a new study using radishes published in Environmental Research, they found that the particles entered roots and eventually accumulated in the edible fleshy parts of the plant.
“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,” said Dr. Nathaniel Clark, the study’s lead author. “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.”
The team grew radishes in a hydroponic system with water containing radiolabeled plastic nanoparticles. Within just five days, millions of particles had moved into the plants: about a quarter ended up in the edible root and 10% in the leaves.
While the study was conducted in a lab setting with one vegetable, it provides clear evidence that plastics can enter crops, adding to past research showing they accumulate in seafood. The findings don’t mean supermarket vegetables are unsafe today, but they highlight a growing concern about how environmental plastics move through the food chain.
Professor Richard Thompson, a senior author, noted, “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.”
The researchers say more studies are needed to understand how widespread the problem may be and what it means for human health. In the meantime, the work underscores the global scale of plastic pollution and the need for prevention at the source.
This study was funded by the Seale Hayne Education Trust and the UK Natural Environment Research Council.