In an early study Jani et al. administred rutile TiO₂ (500 nm) as a 0.1 ml of 2.5 % w/v suspension (12.5 mg/kg BW) to female Sprague Dawley rats, by oral gavage daily for 10 days and detected presence of particles in all the major gut associated lymphoid tissue as well as in distant organs such as the liver, spleen, lung and peritoneal tissue, but not in heart and kidney. The distribution and toxicity of nano- (25 nm, 80 nm) and submicron-sized (155 nm) TiO₂ particles were evaluated in mice administered a large, single, oral dosing (5 g/kg BW) by gavage. In the animals that were sacrificed two weeks later, ICP-MS analysis showed that the particles were retained mainly in liver, spleen, kidney, and lung tissues, indicating that they can be transported to other tissues and organs after uptake by the gastrointestinal tract. Interestingly, although an extremely high dose was administrated, no acute toxicity was observed. In groups exposed to 80 nm and 155 nm particles, histopathological changes were observed in the liver, kidney and in the brain. The biochemical serum parameters also indicated liver, kidney and cardiovascular damage and were higher in mice treated with nano-sized (25 or 80 nm) TiO₂ compared to submicron-sized (155 nm) TiO₂. However, the main weaknesses of this study are the use of extremely high single dose and insufficient characterisation of the particles.

Used for coloring paint, ink, rubber, etc. Inorganic white pigments are widely used as white pigments in plastics such as polyolefin, vinyl resin, ABS resin, polystyrene, polycarbonate, nylon and polyformaldehyde, as well as paints and inks. It is less effective in polyurethane and amino resins, and less suitable in fluoroplastics. It is also used for coloring rubber products, papermaking, varnished cloth, oilcloth, leather, watercolor paints, paper, enamel, etc. Used as an adhesive in the production of electric beads.

Furthermore, the use of titanium dioxide in rubber helps to reduce the environmental impact of rubber manufacturing processes. As a non-toxic and environmentally friendly material, titanium dioxide is safe for use in rubber products that come into contact with food, water, or other sensitive materials. This makes it an attractive choice for manufacturers looking to produce eco-friendly and sustainable rubber goods.

EFSA has updated its safety assessment of the food additive titanium dioxide (E 171), following a request by the European Commission in March 2020. 

In a 2016 study published in Scientifica (Cairo), Egyptian researchers examined the effects of titanium dioxide nanoparticles on the organs of mice by orally administering the food additive daily, for five days. The results showed that the exposure produced “mild to moderate changes in the cytoarchitecture of brain tissue in a time dependent manner.” Furthermore, “Comet assay revealed the apoptotic DNA fragmentation, while PCR-SSCP pattern and direct sequencing showed point mutation of Presenilin 1 gene at exon 5, gene linked to inherited forms of Alzheimer’s disease.” The researchers wrote: “From these findings, “the present study concluded that TiO2NPs is genotoxic and mutagenic to brain tissue which in turn might lead to Alzheimer’s disease incidence.”

Synthesis of vitaminB2@P25TiO₂NPs

What is the FDA limit for titanium dioxide?

The Evolution and Impact of Anatase Titanium Dioxide Manufacturers

One of the main uses of TiO2 powder is as a pigment in paints and coatings. It is valued for its excellent opacity, brightness, and UV resistance, making it ideal for use in exterior paints, industrial coatings, and automotive finishes. TiO2 powder suppliers work closely with paint manufacturers to supply them with the right grade and quantity of TiO2 powder to meet their specific requirements.