Particle size: optimum particle size to produce maximum opacity is 200–300 nm.

Stability and darkening[edit]

Specific gravity:

Barium sulfide is produced by carbothermic reduction of barium sulfate. Zinc sulfate is obtained from a variety of zinc products, often waste, by treatment with sulfuric acid.

There is also some evidence to suggest that exposure to titanium dioxide nanoparticles may be harmful or toxic to the environment, including aquatic life and other organisms. The production and disposal of the mineral may also release pollutants, such as carbon dioxide and sulfur dioxide, into the air and water.

No. The titanium dioxide we use in our toothpastes has been proven safe by health experts around the world. It is used in our toothpastes as a white colourant, in a non-nano form as defined by European regulations. It is an approved colourant in cosmetics, and we comply with all the regulations applicable to it.

Titanium dioxide can boost and brighten colors because of how well it absorbs and also scatters light. In food and drugs, this additive is known as E171 and helps define colors clearly and can prevent degradation (cracking and breakdown of materials) from exposure to sunlight.

Nano-sized TiO₂ generally shows low or no acute toxicity in both invertebrates and vertebrates. However, exposure of Daphnia magna to 20 ppm TiO₂ for 8 consecutive days was found to cause 40 % mortality. Zhu et al. showed minimal toxicity to D. magna after 48 h exposure, while upon chronic exposure for 21 days, D. magna suffered severe growth retardation and mortality. A significant amount of nano-sized TiO₂ was found also accumulated in the body of the animals. Similar findings with coated nano-sized TiO₂ (T-Lite™ SF, T-Lite™ SF-S and T-Lite™ MAX; BASF SE) were reported by Wiench et al. Biochemical measurements showed that exposure to TiO₂ NPs induces significant concentration-dependent antioxidant enzyme activities in D. magna. Lee et al. showed that 7 and 20 nm-sized TiO₂ induced no genotoxic effect in D. magna and in the larva of the aquatic midge Chironomus riparius.

In a statement sent to USA TODAY on Sunday, Justin Comes, vice president of research and development for Skittles maker Mars Wrigley North America, said the company couldn't comment on pending litigation – but that its use of titanium dioxide and all Mars Wrigley ingredients are safe and manufactured in compliance with strict quality and safety requirements established by food safety regulators, including the FDA.

≥100

Market Dynamics

Lithopone 30% is the perfect solution for partial substitution of TiO2 in fillers due to its very soft nature and hardly any shrinkage properties.