Our study presents dosimetric evaluation of activities associated with sealing in glass 72 sources of ²²⁶Ra prepared for utilization, and of the effect of an absorbed dose on a worker’s select laboratory parameters. During 3 h exposure to ²²⁶Ra of activity 31 GBq, it was demonstrated that taking the sources from a bunker in portions only for the time of sealing them in glass, decreases the worker’s exposure to the obtained dose from 91.5 mSv to 6 mSv, and additionally used 5 cm shield to 2 mSv. Nine days after the worker’s absorption of the radiation dose, we observed in laboratory tests disorders expressed by decreased numbers of white blood cells and neutrophils, decreased activity of antioxidative enzymes in erythrocytes, concentrations of protein thiol groups, vascular endothelial growth factors in serum, and an increase of plasma total antioxidant status level, of insulin-like growth factor I level, and urokinase-type plasminogen activator receptor level in blood serum.