In this study, we have identified the response of mast cells of the liver, lungs, heart, thymus, kidneys and skin to the introduction of iron-carbon nanoparticles in the modification of FeC (with the structure of "nucleus-(Fe)-carbon membrane"). The study showed that the liver reacts first to the introduction of nanoparticles on the 1st day of experiment. Mast cells activation in the lungs and heart occurs оn the 7th day after introduction. Mast cells of the thymus and skin are activated on the 30th day of experiment. Mast cells of the kidney do not react to the introduction of iron-carbon nanoparticles.