The Pneumotoxic Effect and Indium Ion Release Induced by Indium Tin Oxide Nanoparticles

With the increasing industrial production and the broaden applications of indium tin oxide (ITO) materials, frequent exposure has posed great concerns for people, especially the workers in the indium related manufacturing plants. The exposed-workers have been reported to adverse effect and even die from the ITO-induced pulmonary disorders called "indium lung." In addition to the epidemiologic studies, the increasing animal studies also demonstrated the lung injuries induced by the acute or chronic respiratory exposure of ITO nanoparticles (ITO NPs). They could enter into the cells owing to the small particle size and induce oxidative stress, inflammatory responses, cytotoxicity or even genotoxicity. The indium ions released from the ITO particles via lysosomal acidification considered as the actual entity responsible for the toxicity of ITO NPs. To date, no effective therapies are available against ITO-induced pulmonary diseases, which calls for the full explorations of the pathological factors. Our present mini-review summarizes the current reports on ITO nanoparticles-induced pneumotoxic effect with focus on the indium ion release, which could help warrant the health risks of ITO and other ITO-based materials.