Researchers at Plymouth University in the UK have found for the first time that nano-sized plastic particles can penetrate the root barrier and infiltrate the edible parts of carrots during crop growth. The research results published in Environmental Research suggest that humans may unknowingly ingest nanoscale plastics from the environment through foods such as vegetables. The researchers explained that they have previously demonstrated that nanoscale plastic particles can be quickly absorbed and accumulated in shellfish and fish, and the latest research further confirms that these particles can also migrate and deposit in plants. In the experiment, they placed carrots in a hydroponic system and exposed their non fleshy roots to a solution of polystyrene nano plastic particles containing radiolabeled carbon. Five days later, they checked the penetration of particles into the plant body. It was found that nearly 5% of the particles in the solution were retained by the root system, equivalent to millions of nano-sized plastic particles entering the working object. About a quarter of it enters the fleshy roots, which are the parts consumed by people, and about 10% accumulates in the leaves. The first author of the study, Nathaniel Clark, a lecturer in science at Plymouth University, stated that plant roots have a barrier called the Kjeldahl Belt, which theoretically should be able to block harmful particles from entering. This is the first confirmation that nanoscale plastics can break through this barrier, accumulate in plants, and potentially be transmitted through the food chain to organisms that consume them. This phenomenon is likely not limited to carrots. This study provides clear evidence that nanoscale plastic particles in the environment can not only accumulate in seafood, but also enter vegetables. This once again reveals the cumulative effects and potential hazards that nanoscale plastic particles may bring to the environment and human health. (New Society)