In vivo acute toxicity of titanium dioxide nanoparticles to mice after intraperitioneal injection

Because of its excellent optical performance and electrical properties, TiO2 has a wide range of applications in many fields. It is often considered to be physiologically inert to humans. However, some recent studies have reported that nano‐sized TiO2 may generate potential harm to the environment and humans. In this paper the in vivo acute toxicity of nano‐sized TiO2 particles to adult mice was investigated. Mice were injected with different dosages of nano‐sized TiO2 (0, 324, 648, 972, 1296, 1944 or 2592 mg kg–1). The effects of particles on serum biochemical levels were evaluated at various time points (24 h, 48 h, 7 days and 14 days). Tissues (spleen, heart, lung, kidney and liver) were collected for titanium content analysis and histopathological examination. Treated mice showed signs of acute toxicity such as passive behavior, loss of appetite, tremor and lethargy. Slightly elevated levels of the enzymes alanine aminotransferase and aspartate aminotransferase were found from the biochemical tests of serum whereas blood urea nitrogen was not significantly affected (P