Currently, a lot of new chemical compounds are registered in the world, some of them are used in various fields of medicine, pharmaceuticals or related fields. In this case, each of the introduced chemical compounds must be assessed toxicologically. In vitro cell models are used to elucidate the mechanisms of differentiation and proliferation, interaction of cells with the environment, adaptation, aging, biological activity, malignant transformation, for the diagnosis and treatment of hereditary diseases, and as test objects when testing new pharmacological substances. The review presents the advantages of using cell models, provides methods for studying the cytotoxic effects of target agents, and discusses the system for controlling the contamination of materials. In addition, the necessity to search for new cytostatics in the context of a steady trend of growth in new cases of cancer and the imperfections of existing anticancer drugs is discussed, and studies of the cytotoxicity of a number of promising tetrahydroisoquinolines, their structural-functional relationship, the type of triggering of cell death and the mechanism of manifestation of cytotoxicity are presented.