Titanium dioxide nanoparticles: a review of current toxicological data.

Titanium dioxide nanoparticles: a review of current toxicological data.

Particle and fibre toxicology (2013-04-17)

Hongbo Shi, Ruth Magaye, Vincent Castranova, Jinshun Zhao

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.

MATERIALS

Product Number

Brand

Product Description

IRMM531B

Titanium, IRMM^®, certified reference material, 0.5 mm foil

348791

Sigma-Aldrich

Titanium, foil, thickness 0.127 mm, 99.7% trace metals basis

266035

Sigma-Aldrich

Titanium, wire, diam. 1.0 mm, 99.99% trace metals basis

IRMM531C

Titanium, IRMM^®, certified reference material, 0.5 mm wire

369489

Sigma-Aldrich

Titanium, foil, thickness 2.0 mm, 99.7% trace metals basis

267902

Sigma-Aldrich

Titanium, wire, diam. 0.81 mm, 99.7% trace metals basis

460400

Sigma-Aldrich

Titanium, wire, diam. 0.25 mm, 99.7% trace metals basis

305812

Sigma-Aldrich

Titanium, 5-10 mm, ≥99.99% trace metals basis (purity exclusive of Na and K content)

348848

Sigma-Aldrich

Titanium, foil, thickness 0.025 mm, 99.98% trace metals basis

GF65336700

Titanium, rod, 200mm, diameter 2mm, annealed, 99.6+%

GF76772391

Titanium, rod, 100mm, diameter 10mm, annealed, 99.6+%

GF87716997

Titanium, rod, 100mm, diameter 16mm, as drawn, 99.99+%

GF06082286

Titanium, microfoil, disks, 10mm, thinness 1.0μm, specific density 429μg/cm², permanent mylar 3.5μm support, 99.6+%

GF03916290

Titanium, rod, 490mm, diameter 2mm, annealed, 99.6+%

GF68670366

Titanium, tube, 1220mm, outside diameter 2.03mm, inside diameter 1.55mm, wall thickness 0.24mm, annealed, 99.6+%

GF82517722

Titanium, tube, 1000mm, outside diameter 6.35mm, inside diameter 4.57mm, wall thickness 0.89mm, annealed, 99.6+%

GF50171318

Titanium, rod, 25mm, diameter 16mm, as drawn, 99.99+%

GF03838282

Titanium, rod, 500mm, diameter 1.5mm, annealed, 99.6+%

GF04311638

Titanium, rod, 100mm, diameter 6mm, annealed, 99.6+%

GF25290581

Titanium, tube, 1000mm, outside diameter 25.4mm, inside diameter 23.62mm, wall thickness 0.89mm, annealed, 99.6+%

GF20882998

Titanium, rod, 200mm, diameter 5mm, annealed, 99.6+%

GF65694426

Titanium, tube, 100mm, outside diameter 1.6mm, inside diameter 1.2mm, wall thickness 0.2mm, hard, 99.6+%

GF54978249

Titanium, rod, 200mm, diameter 4mm, annealed, 99.6+%

GF34106363

Titanium, rod, 1000mm, diameter 1.5mm, annealed, 99.6+%

GF12929744

Titanium, microfoil, disks, 25mm, thinness 0.25μm, specific density 112.6μg/cm², permanent mylar 3.5μm support, 99.6+%

GF72503827

Titanium, tube, 100mm, outside diameter 2.03mm, inside diameter 1.63mm, wall thickness 0.2mm, annealed, 99.6+%

GF69259315

Titanium, rod, 500mm, diameter 6mm, annealed, 99.6+%

GF62676759

Titanium, rod, 200mm, diameter 2mm, as drawn, 99.99+%

GF85496664

Titanium, tube, 1000mm, outside diameter 9.5mm, inside diameter 8.2mm, wall thickness 0.65mm, annealed, 99.6+%

GF28411703

Titanium, tube, 100mm, outside diameter 10.3mm, inside diameter 8.7mm, wall thickness 0.8mm, annealed, 99.6+%