FIELD: medicine.SUBSTANCE: invention refers to medicine, namely hygiene, clinical-laboratory diagnostics, cytology, and can be used for examination of oral epithelial cells in workers exposed to harmful factors of working medium and labour process. Buccal epithelial smears are made, alizarin red C staining, fluorescent microscopy of smears. Further, the cell structure in the smears is quantified by calculating the fluorescence cytochemical coefficient, which expresses the nucleus and cytoplasm features, as well as a degree of cell differentiation and a cell counted by counting with a distribution corresponding to the content of the red C alisarin dye therein. Total of 100 cells are examined. Average cytochemical coefficient - ACC is calculated by formula:where Ne is the amount of epithelial cells. 1 point - non-fluorescent cells in range of 580–680 nm, not colored by alizarin; 2 points - weakly fluorescent cytoplasm cells in range of 580–680 nm, 90 % of the core area and a perinuclear region, fluoresces in range of 400–580 nm; 3 points - nucleus fluoresces in range of 400–580 nm, alizarin-colored cytoplasmic structures, fluoresces in range of 580–680 nm; 4 points - nucleus and intracellular cytoplasmic structures colored with alizarin, fluoresce in range of 580–680 nm; 5 points - nucleus and cytoplasma are intensely fluorescent in range of 580–680 nm.EFFECT: method enables detecting the cytochemical features of the calcium-dependent mechanism controlling the differentiation of buccal epithelium, due to objective assessment of the state of cells when viewed under an optical microscope coloured smears, as well as the possibility of using the fluorescent microscopy to assess the DNA-intercalating properties of alizarin red C, which stains buccal epithelial cell nuclei, that provides rationale for preventive measures, one of which elements is application of specialized food products possessing tread properties and increasing overall body resistance.1 cl, 2 tbl, 1 exИзоб