Microplastics have not been with us for long, and yet they are present in almost all ecosystems on the planet . They have been found in the soil, in rivers, in the food we eat, in bottled water and even in our own body, in the lungs and in the blood. Now, a team of researchers has located microplastics in the water that accumulates in the leaves of a type of thistle.
Thistles of the genus Dipsacus have opposite leaves that grow on the stem one above the other at various levels. Where they join the stem, the leaves form cup-like structures where rainwater is collected. These “cups” are known as telmatians . Well, within these water deposits live certain organisms.
It was precisely the study of these organisms that often go unnoticed that attracted the team of researchers made up of Katarína Fogašová, Peter Manko and Jozef Obona, from the University of Prešov (Slovakia). While studying these aquatic microcosms, scientists found different colored fibers and fragments . They realized that they were microplastics. Some of them were 2.4 millimeters long .
“Phytotelmata are a relatively common but overlooked aquatic microcosm, with a very short-term occurrence of only 3 to 4 months,” say the researchers in their study, which has been published in the journal BioRisk .” These phytotelmata are very small and short-lived, so the question is how they became contaminated with microplastics.”
Since no polluting source was found in the area, the researchers believe that the microplastics were most likely found in the atmosphere . Another hypothesis is that the snails have transported them from the ground or from other plants, on their body or inside it.
This is the first time that microplastics have been found in the water deposits that some plants have on their leaves. According to the researchers, it is further proof that this type of contamination is spreading through different routes and probably no environment on the planet is safe . Scientists call the finding “pretty disheartening.”
The researchers have studied a specific plant, the Cardencha fitotelmata . This type of thistle could be used as a natural detector that indicates the amount of microplastics that is present in a certain ecosystem, their potential impact on the plants themselves and on the organisms that are linked to them.
“Our publication, therefore, not only provides the first discovery of microplastic contamination in habitats of this type, but also the first proposal for a new approach for the use of cardencha phytotelmas and similar microecosystems provided by plants (or artificially created), as bioindicators of the presence of microplastics in the environment, of the possible sources and pathways of their spread through the environment, and of the spatio-temporal changes of microplastic contamination”, say the researchers.
Referencia: Fogašová K, Manko P, Oboňa J. 2022. The first evidence of microplastics in plant-formed fresh-water micro-ecosystems: Dipsacus teasel phytotelmata in Slovakia contaminated with MPs. BioRisk. DOI: https://doi.org/10.3897/biorisk.18.87433