Assessment of prospects for the use of unicellular hydrobionts as test objects in the study of biotoxicity of ultradispersed metal particles

Abstract

Active development of nanomaterials in various areas of human activity leads to their intensive release into the environment. Nanomaterials in aquatic ecosystems are of particular concern, leading to changes in water quality and dangerous for representatives of aquabiocenosis - aquatic invertebrates, bioaccumulating technogenic nanoparticles. In this regard, studies on the selection of an optimal test object from representatives of hydrobionts, having the most adequate response to various, including toxic, effects of nanomaterials, with further prospect of determining the potential risks that arise when they enter aquatic biocenoses are relevant. Cultures of freshwater ciliate of Stylonychia mytilus (wild strain) in the phase of exponential growth and Paramecium caudatum were selected as the objects of the study. Survival was a determined parameter. 9 laboratory preparations of ultradispersed particles of metals (zinc, copper, ferrum, argentum, cobalt, titanium, aluminum, molybdenum, nickel) were used in studies. The analysis of the effects of ultradispersed metal particles revealed a negative biological effect on Paramecium caudatum and Stylonychia mytilus. Paramecium caudatum was the most sensitive to increasing concentrations of nanoparticles, as evidenced by the death of individuals after 10 minutes of contact. In turn, the death of Stylonychia mytilus was observed only at the 60th minute of exposure. Based on the above, Paramecium caudatum culture can be proposed as an express test object, giving a response at the 10th minute of the experiment. For studies assessing various types of toxicity that require a longer contact time, Stylonychia mytilus is a more suitable test object, since the effect of nanoparticles on the cell can be observed for 60-180 minutes or more.