Toxicity of nanosilver in intragastric studies: Biodistribution and metabolic effects

The unique physicochemical properties of silver nanoparticles explain their extensive application in consumer goods, food, and medicinal products. However, the biological effects of nanosilver after peroral exposure of mammals are still debatable. This study describes the biodistribution and biological action of 12nm non-coated silver nanoparticles intragastrically administered to male rats after acute (single exposure) and sub-acute (multiple exposures over 30 days) toxicity experiments. The daily doses were 2000 and 250mg/kg of body weight for single and multiple administrations, respectively. Silver tissue detection was conducted by elemental analysis with the help of atomic absorption spectroscopy. An estimation of the state of exposed animals was made and the dynamics of hematological and biochemical parameters of rats was studied. It was demonstrated that single and multiple administrations resulted in silver accumulation in the liver, kidneys, spleen, stomach, and small intestine. After both one- and repeated-dose exposures, the highest Ag contents were detected in the liver (0.87±0.37μg/g of organ) and kidneys (0.24±0.02μg/g of organ). The concentrations of silver detected in tissues were far smaller than the administered doses (