Introduction: The current growth trend of the market for nanomaterials for medicine exacerbates the problem of their safe use. It is generally accepted that most nanomaterials are not hazardous by themselves. However, there is still uncertainty regarding nanosafety. Consequently, nanosafety should be assessed using model systems and organisms that are as close as possible to natural ecosystems. In this regard, the question of searching for model organisms for studying the ecotoxicity of engineered nanomaterials is actualized.

Aim: To analyze scientific literature which describe various methodologies correlating individual properties of nanomaterials and their biological influence, taking into account the position of model organisms in the hierarchy of the ecosystem.

Materials and methods: Analysis of sources using the electronic resource library of SumDu (scientific databases EBSCO, Scopus) and open scientific database PubMed.

Results: Various methodological approaches are used to study the behavior of nanoparticles (NPs) in the environment and assess the degree of their toxic effect on living objects, which consider, firstly, the physical and chemical properties of NPs. In addition, the influence of some environmental factors (ionic strength, temperature, pH, salinity, etc.) is not excluded. In numerous sources, attention is focused on aquatic ecosystems, which are more susceptible to pollution by NPs. In this regard, the necessity of using simple aquaorganisms for assessing the toxic effect of NPs on biosystems is substantiated. Bacteria and fungi found in natural aquatic ecosystems are often used for biotesting NPs. Recent in vivo studies have shown that microbiota can enhance the production of extracellular polysaccharides in response to exposure to NPs. The absorption processes of various NPs by crustaceans Daphnia magna, polychaetes Nereis diversicolor, and freshwater algae Chlorella vulgaris and Ochromonas danica have been well studied. The mode of nanomaterial biodegradation is particularly helpful in the certification of newly engineered nanomaterials.

Conclusion: The variety nanomaterials for medicine, the growth of the arsenal of which is generally recognized and dynamic, makes it necessary to use express, economically notable, and reliable biotesting to minimize the toxic effect on the environment. From the point of view of the authors of this work, simple life organisms can provide a practical assessment of the ecotoxicity of NPs.