Histopathological effects of titanium dioxide nanoparticles on the liver in rats by light and transmission electron microscopy

Background: As one of the most influential and in-demand nanoparticles for commercial applications, titanium dioxide nanoparticles are commonly used in industry as a white pigment, in cosmetic and health products, and as a disinfection agent. In food and drugs, this additive is known as E171 and helps define colors clearly and can prevent UV degradation. This study used light and transmission electron microscopy to examine the effects of titanium dioxide nanoparticles on the liver in rats. Methods: Titanium dioxide nanoparticles were administered to 40 rats at 0, 10, 20, and 50 mg per kilogram of rat body weight suspended in one millilitre of distilled water over 60 days (every second day) by oral gavage.The rats were euthanized and tissue samples were dissected from the liver for light (thick section)and transmission electron (thin section) microscopy study. Results: Histopathological examinations in treated groups revealed dilation of hepatic sinusoids, hepatocytes degeneration and necrosis, observed as cellular swelling, cytoplasmic vacuolation, and loss of nuclei, nuclear pyknosis, karyorrhexis, and karyolysis. Some pathologic changes were also observed in mitochondria; the enlargement of the mitochondrial membrane and cristae, the disintegration of the mitochondria, and the destruction of the cristae were evident in response to all doses utilized in the study. Conclusions: Our studydemonstrated that the continuous use of titanium dioxide nanoparticles(E171) can cause histopathological damages in the liver and disrupt the function of this organ. Consequently, it is recommended to limit the use of this ingredient in industrial, sanitary, foods, and cosmetic products.