In a 2017 study published in Scientific Reports, researchers exposed rats to human-relevant levels of E171 to examine the effects of intestinal inflammation and carcinogenesis. They saw that “a 100-day E171 treatment promoted colon microinflammation and initiated preneoplastic lesions while also fostering the growth of aberrant crypt foci in a chemically induced carcinogenesis model.” They continued: “Stimulation of immune cells isolated from Peyer’s Patches [which are clusters of lymphoid follicles found in the intestine] showed a decrease in Thelper (Th)-1 IFN-γ secretion, while splenic Th1/Th17 inflammatory responses sharply increased,” researchers wrote. “A 100-day titanium dioxide treatment promoted colon microinflammation and initiated preneoplastic lesions.” The scientists concluded: “These data should be considered for risk assessments of the susceptibility to Th17-driven autoimmune diseases and to colorectal cancer in humans exposed to TiO2 from dietary sources.”
≥30.0
2. Particle Size The application often dictates the required particle size. Suppliers typically offer various grades of barium sulphate, categorized by their particle size distribution. For example, finer particle sizes are often favored in cosmetic applications, while coarser grades may be used in construction materials.
In conclusion, titanium IV oxide is a versatile compound that is used in a wide range of industries. From sunscreen to paints to food coloring to pharmaceuticals, titanium dioxide plays a vital role in many products. Its unique properties, such as UV protection, brightness, and stability, make it an essential ingredient in various applications. As technology continues to advance, titanium IV oxide will likely continue to play a key role in the manufacturing of innovative products.
Health Canada's Food Directorate recently completed a “state of the science” report on titanium dioxide (TiO2) as a food additive. Food-grade TiO2 is a white powder made up of small particles that has been permitted in Canada and internationally for many years as a food additive to whiten or brighten foods. Food-grade TiO2 has long been considered safe in Canada and in other countries when eaten as part of the diet.


Other research suggests that E171 could cause harm; however, those research processes did not consider how people are typically exposed to E171. Research that adds E171 to drinking water, utilizes direct injections, or gives research animals E171 through a feeding apparatus is not replicating typical human exposure.
Having thus described the origin and uses of the pigment, we now come to the question, what is lithopone? It is, in short, a chemical compound usually consisting of 30.5 per cent zinc sulphide, 1.5 per cent zinc oxide and 68 per cent barium sulphate, but these proportions vary slightly in the different makes. Lithopone of this composition is sold as the highest grade, either as red seal or green seal, as it best suits the idea of the manufacturer. Many manufacturers, especially in Europe, sell and also export other brands under other seals, containing 24, 20, 18 and as little as 12 per cent of zinc sulphide with very small percentages of zinc oxide, the balance being usually barium sulphate, but sometimes certain portions of China clay or gypsum (calcium sulphate) or whiting (calcium carbonate). Such brands are not a chemical compound, but mechanical mixtures of the chemically compounded lithopone and the admixtures referred to.
Genotoxicity Assessment