Comparison of toxicity of aqueous suspension of nano- and microfine silica in subchronic experiment

In subchronic experiment on Wistar’s white male rats the negative effects have been studied and the comparative assessment of toxicity of an aqueous suspension of nano-and microfine silica has been carried out. It was found that by intragastric administration for 90 days of the dose of 14.6 mg/kg, corresponding to the predicted threshold dose (LOAEL), the aqueous suspension of nanosized silica causes immune irritating, cytolytic and inflammatory effects, verified by the deviation of hematologic parameters and morphological changes in tissues bodies / or target systems (liver, stomach, jejunum and colon, immune system). Micro-sized silica causes predominantly an inflammatory effect in the mucosa of stomach, jejunum and colon.