Аннотация:The onset of large-scale industrial and household application of nanoobjects has boosted interestin research of interactions between nanoparticles of various nature and biological objects. However, theimpact of nanomaterials on biological systems, including humans, is not fully understood. The resultsobtained recently in various laboratories do not give an accurate answer about their safety. Previously, wefound that exposure of bacterial cells to single- and multi-walled carbon nanotubes resulted in their decay. Toexplain this effect, in this work we analyzed the effect of two other types of carbon nanoparticles, diamondand graphite, on bacterial cells. Engineered cells of Escherichia coli strain K12 TGI with a luminous phenotype were used as a test system to study the effects of diamond nanoparticles obtained by the detonationmethod and of graphite nanoparticles obtained by sonication. Based on bioluminescence and scanning electron microscopy data, it was shown that these types of nanoparticles were not toxic to bacterial cells. Ourresults demonstrate that the safety of nanomaterials depends not only on their composition, but also on theirinternal structure. This will help to further develop safety criteria for nanomaterials and to establish the conditions and standards for their use.