Introduction. Silicon compounds are widely used in industrial production; therefore, people are highly likely to have constant contact with this element. Hepatic macrophages are crucial in maintaining homeostasis in the liver; thus, investigating their reaction can provide new information on their possible participation in the inflammation induced by silicon supplied with water. The aim was to explore how Iba1+ and CD68+ liver cells in laboratory rats respond to the intake of silicon with drinking water at a concentration of 10 mg/l during two months. Materials and methods. Laboratory rats were divided into 2 groups: the control group (n=5) received drinking bottled water ad libitum, whereas the experimental one was given the same water with addition of sodium metasilicate nonahydrate (Na2SiO3 × 9 H2O) at a concentration of 10 mg/l in terms of silicon. This corresponded to the maximum allowable concentration, according to SanPiN 2.1.4.1074-01 in force at the time of the experiment. The animals were withdrawn from the experiment 2 months after had begun. The liver was removed and fixed in 10% neutral formalin and embedded in paraffin according to the standard protocol. Iba1+ and CD68+ structures were detected with immunohistochemical and immunofluorescence methods using specific antibodies. Results. We compared the expression patterns of the two macrophage markers and detected that in the experimental group, the median area of Iba1-positive cells in the livers of rats had a 0.87-time decrease compared to that in the control group (p=0.000006). The experimental group showed an increase in the number of Iba1+ and CD68+ cells (p=0.02 and p=0.01, respectively). We revealed that in the experimental group, immunofluorescence in Iba-1+ liver macrophages decreased (p=0.01), whereas that in CD68+ macrophages increased (p=0.27). Conclusion. The intake of water-soluble silicon at a concentration of 10 mg/l activates liver macrophages in a relatively short period of exposure (two months). Therefore, the safety of silicon compounds in the conditions of their constant supply should be studied more thoroughly.