Bandas I. Integrated Risk Assessment in Case of Simultaneous Intake of Silicone Dioxide Nanoparticles and Lead Acetate Chemical Toxicant.

The interpretation of the mechanisms of silicone dioxide nanoparticles and lead acetate interaction in cases of their combined effect on the organism is presented in the thesis. It has been established that SiO2 nanoparticles increase the toxic effect of lead on liver (alanine and aspartate aminotransferases as well as alkaline phosphatase activities are elevated), intensify the oxidative and nitro-oxidative stress caused by lead acetate (oxidation of lipids and proteins processes are stimulated, antioxidant system is inhibited, NO-synthase activity and NOx contents are increased), increase the negative effect of lead on the immune system (TNF-?, IL-1?, IL-6, immunoglobulins A, M and G as well as circulating immune complexes levels are increased, but IL-4 and IL-10 are decreased), enhance the capability of lead acetate to increase the production of intracellular reactive oxygen species, the number of neutrophils with reduced mitochondrial transmembrane potential as well as blood neutrophils with apoptotic and necrotic changes.The administration of nano-SiO2 in combination with lead acetate results in the pronounced structural changes in liver, kidney and spleen tissues.