Microplastic (MP), i.e. tiny plastic particles less than 5 millimeters in length, can now be found in the ocean and other aquatic ecosystems. Even in our seafood and salt. As microplastics began to spread everywhere, scientists began to worry about its transfer from the environment to the food chain and the potential impact on human health. Scientists from the Chinese Academy of Sciences (CAS) recently discovered that MP really pollutes edible plants, including the vegetables we eat. The study was published in the journal Nature Sustainability.
Most microplastics are thrown into the earth’s environment and accumulate in large quantities in the soil. In addition, secondary particles are formed by the decomposition of plastics. Wastewater, an important source of water for agricultural irrigation, also contains small particles of MP.
Despite the prevalence of microplastics in the environment, the question of its absorption by agricultural plants was not given much attention.
For decades, scientists believed that plastic particles were simply too large to pass through the physical barriers of intact plant tissue. But this new study refutes this assumption.
Cracks on the lateral roots of lettuce and wheat crops can absorb microplastics from surrounding soil and water. It can be transferred from the roots to the edible parts of the culture, scientists said.
Scientists already knew that particles up to 50 nanometers in size could penetrate plant roots. But a group of Professor Luo showed from the Chinese Academy of Sciences that particles about 40 times this size can also get into plants.
The microplastic particles identified in this study were spherical, up to 2 micrometers in size with a small degree of mechanical flexibility. These features allowed them to squeeze into the small apoplastic space of the plant root cells.
Scientists have suggested that particles larger than those they studied can also be absorbed by plants.
These data shed new light on the possibility of transferring microplastics along the food chain. If particles enter our crops, they also enter our meat and dairy products. It also raises the question of how microplastics affect people’s health, and there is no clear answer to this question yet.