Microplastics are a global environmental problem, because they can enter different ecosystems through a variety of sources. While the amount of microplastics in the environment is constantly increasing, it is very difficult to remove them. Most common types of microplastics in the environment are in the form of fragments, formed during the fragmentation of larger plastic items. A large number of microplastics in the environment are also tire wear particles, which are generated from the abrasion of car tires. They can become airborne or enter aquatic ecosystems as part of road dust. When tire wear particles come into contact with aquatic plants, they can be adsorbed on the surface and thus enter the food chain, as plants are also a source of food to other organisms. On the other hand, adsorption can be a way to develop phytoremediation method, a method to remove microplastics from the aquatic environment. Therefore, the purpose of the experimental work was to determine the effects of microplastics from car tires on duckweed (Lemna minor), and to determine the amount of adsorbed microplastics on the plant. Effects were evaluated by determining the specific growth rate, the length of roots and the concentration of the photosynthetic pigments. Microplastics had no effects on the specific growth rate and on the photosynthetic pigments, while they inhibited the root length. We also found that the amount of adsorbed microplastics fluctuated during the experiment. The results suggest that the duckweed has the potential for phytoremediation of microplastics from car tires, but it would be necessary to further investigate the mechanisms and the effects of environmental factors on adsorption.
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