Freshwater algae show low-to-moderate susceptibility to TiO₂ exposure, with more pronounced toxic effects in the presence of UV irradiation. It has also been shown that nano-sized TiO₂ is significantly more toxic to algae Pseudokirchneriella sub-capitata than submicron-sized TiO₂. Hund-Rinke and Simon  reported that UV irradiated 25 nm TiO₂ NPs are more toxic to green freshwater algae Desmodesmus subspicatus than UV irradiated 50 nm particles, which is in agreement with Hartmann et al. UV irradiated TiO₂ NPs also inactivated other algae species such as Anabaena, Microcystis, Melsoira and Chroococcus. It was demonstrated that smaller particles have a greater potential to penetrate the cell interior than submicron-sized particles and larger aggregates. Studies have shown that the amount of TiO₂ adsorbed on algal cells can be up to 2.3 times their own weight.

Chinese anatase titanium dioxide has become a popular topic in the field of materials science due to its unique properties and wide range of applications. Anatase titanium dioxide is a type of titanium dioxide with the chemical formula TiO2, and is known for its high refractive index, excellent UV resistance, and good photocatalytic activity.

Lithopone

Titanium dioxide can amplify and brighten white opacity because of its exceptional light-scattering properties. In food and drugs, these properties help to define colors clearly and can prevent products from UV degradation. 

It's also used in sunscreens as a UV filtering ingredient, helping to protect a person's skin by blocking absorption the ultraviolet light that can cause sunburn and cancer.

Over the last several years, nanoparticles have come under scrutiny for adverse health effects. Nanoparticles are ultrafine particles between 1 to 100 nanometers in diameter. (To put this in perspective, the average human hair is around 80,000 nanometers thick.) Because of their size, which can be engineered and manipulated at the atomic or molecular level, nanoparticles exhibit unique physical, chemical, and biological properties. Titanium dioxide is one of the most commonly produced nanoparticles in the world.

When used as a base or colorant in a product, titanium dioxide becomes handy in formulas meant to offer a lot of brightness and opacity. Titanium dioxide is so pigmented, in fact, that it’s used not only in white and pastel-colored products but also in darker shades, as well.

The toxicity of P25TiO₂NPs under UV radiation could be even higher when combined with other usual components of sunscreens Indeed, Soler de la Vega et al. advise that combination with parabens increases the toxicity of the final cosmetic mixture [53].

Fig. 4. Hemolysis (%) values of samples, A: 0.2 mg/mL P25TiO₂NPs; B: 0.02 mg/mL P25TiO₂NPs; C: 0.2 mg/mL VitaminB2@P25TiO₂NPs; D: 0.02 mg/mL VitaminB2@P25TiO₂NPs after 3 h of irradiation (red) and 6 h (blue). SD <5 for all samples and p <0.05 between C-D and A-B.

The CaCO3 and TiO2 factory plays a crucial role in producing these materials on a large scale to meet the growing demand from various industries. The factory utilizes advanced technology and processes to extract and refine CaCO3 and TiO2 from natural resources such as limestone and mineral sands. The production process involves crushing, grinding, and chemical treatment to obtain the desired properties of CaCO3 and TiO2.

How is titanium dioxide extracted?

In 2023, California and New York proposed banning several food additives that are banned in Europe but legal in the United States. Titanium dioxide was among the five proposed to be banned, but in September, the additive was removed from the list of additives from the California ban list.

Synthesis of vitaminB2@P25TiO₂NPs