Titanium dioxide nanoparticles: a review of current toxicological data

Abstract

Titanium dioxide (TiO2) nanoparticles (NPs) are manufactured worldwide in large quantities for use in a wide range of applications. TiO2 NPs possess different physicochemical properties compared to their fine particle (FP) analogs, which might alter their bioactivity. Most of the literature cited here has focused on the respiratory system, showing the importance of inhalation as the primary route for TiO2 NP exposure in the workplace. TiO2 NPs may translocate to systemic organs from the lung and gastrointestinal tract (GIT) although the rate of translocation appears low. There have also been studies focusing on other potential routes of human exposure. Oral exposure mainly occurs through food products containing TiO2 NP-additives. Most dermal exposure studies, whether in vivo or in vitro, report that TiO2 NPs do not penetrate the stratum corneum (SC). In the field of nanomedicine, intravenous injection can deliver TiO2 nanoparticulate carriers directly into the human body. Upon intravenous exposure, TiO2 NPs can induce pathological lesions of the liver, spleen, kidneys, and brain. We have also shown here that most of these effects may be due to the use of very high doses of TiO2 NPs. There is also an enormous lack of epidemiological data regarding TiO2 NPs in spite of its increased production and use. However, long-term inhalation studies in rats have reported lung tumors. This review summarizes the current knowledge on the toxicology of TiO2 NPs and points out areas where further information is needed.

Imaging flow cytometry assays for quantifying pigment grade titanium dioxide particle internalization and interactions with immune cells in whole blood

“…Routes of exposure include the skin (e.g., sunscreens), the lungs (e.g., during painting), and the gastrointestinal tract (e.g., from processed foods, toothpaste, nutraceuticals, and pharmaceuticals) 1. Surgical titanium implants may also acquire oxide surfaces, which gradually wear releasing TiO 2 particles.…”

Fungicidal effect of combined nano TiO2 with erythrosine for mediated photodynamic therapy on Candida albicans: an in vitro study

“…There are studies about erythrosine as a photosensitizer for use in killing Staphylococcus aureus [5], Streptococcus mutans [6], and C. albicans [7,8] when activated by green light. Titanium dioxide is an oxide of titanium that has been widely used in industrial and consumer products [9], whose light-curing unit is blue LED wavelengths of 400-500 nm [10]. It has been widely used in the dental clinic to treat resin composite or glass ionomer.…”

Potential Ameliorative Role of N-Acetylcysteine Against Testicular Dysfunction Induced by Titanium Dioxide in Male Albino Rats

“…Numerous studies have unequivocally shown that TiO2 exposure can migrate through different routes and accumulate in various organs (Chen et al, 2009;Shi et al, 2013;Jia et al, 2013), which, in turn cause oxidative stress, inflammation and apoptosis resulting in organ injury and failure. Dysfunction of the testes in turn affect reproduction and affects the function of the reproductive system (Jia et al, 2013).…”

“…Higher doses of TiO2 nanoparticles (324-2592 mg kg −1 bw) are accumulated in various organs as spleen, liver, kidney, lung and testes (Chen et al, 2009). Upon exposure to TiO2, pathological lesions occur in the liver, spleen, kidneys, testes and brain (Shi et al, 2013;Jia et al, 2013). Consequently disruption in organ function occur and alteration in inflammatory and defensive mechanisms of body.…”