Zinc oxide. Zinc oxide is a popular cross-linking agent for rubber and for various resins. It is essential in the formulation of solvent-borne polychloroprene adhesives. Furthermore, zinc oxide is a good UV stabilizer, has biocidal activity and has a relatively high refractive index (2.0) which makes it an efficient white pigment. Some typical properties are: density 5.6 g/cm³; particle size 0.036-3 μm; oil absorption 10–20 g/100 g; specific surface area 10–45 m²/g. Zinc oxide is produced by reaction of the metal in the vapour state with oxygen. Zinc oxide is nonporous and is quite pure. Thus, the high surface area of some grades is due to the small particle size of zinc oxide. Some grades, especially for use in the rubber industry, are surface modified by deposition of 0.2-0.4% of stearic acid, propionic acid, or light oil [47].

In summary, the Food Directorate's position is that there is no conclusive scientific evidence that the food additive TiO₂ is a concern for human health. This is based on a review of the available scientific data relevant to food uses of TiO₂. However, we will continue to monitor the emerging science on the safety of TiO₂ as a food additive and may revisit our position if new scientific information becomes available.

Health advocates urge US regulators to ban common food coloring additive, by Tom Perkins, The Guardian, June 2, 2023

The main concern with nanoparticles is that they are so tiny that they are absorbed into the skin more than we want them (ideally sunscreen should remain on the surface of the skin). Once absorbed they might form unwanted complexes with proteins and they might promote the formation of evil free radicals. But do not panic, these are concerns under investigation. A 2009 review article about the safety of nanoparticles summarizes this, to date, in-vivo and in-vitro studies have not demonstrated percutaneous penetration of nanosized particles in titanium dioxide and zinc oxide sunscreens. The English translation is, so far it looks like sunscreens with nanoparticles do stay on the surface of the skin where they should be.  

In conclusion, lithopone is an essential ingredient in the leather industry, providing both aesthetic appeal and practical benefits for leather suppliers. Its ability to create vibrant colors, excellent covering power, cost-effectiveness, and versatility make it a valuable asset in the production of high-quality leather goods. By choosing the right lithopone suppliers and incorporating this pigment into their manufacturing process, leather suppliers can enhance the appeal and durability of their products to meet the demands of the market.

While the anatase titanium dioxide market is robust, it faces challenges such as regulatory compliance and environmental concerns related to extraction and processing. Manufacturers are increasingly adopting sustainable practices, focusing on recycling materials and minimizing waste in production processes. Innovations in nanotechnology are also leading to the development of more efficient and eco-friendly synthesis methods that can further enhance the properties of anatase TiO2.

Fig. 8. Selected images of skin stratus treated with P25TiO₂NPs 10% (left) and VitaminB2@P25TiO₂NPs 10% (right) under light, showing no penetration of the nanoparticles (white arrows) beyond the outer stratum corneum.

Conclusion:

0.3% Max

Biointerfaces, Biomimicking, and Biohybrid Systems

As of August 7, the use of titanium dioxide in food is banned in the European Union. Europe is taking a precautionary principle approach based on findings from the European Food Safety Authority (EFSA).