In 2021, the European Food Safety Authority concluded that titanium dioxide is no longer safe in foods due to the same concerns over nanoparticles. As a result, titanium dioxide is now banned as a food additive in the EU. Although studies have shown that the absorption of ingested titanium dioxide is low, evidence suggests that titanium dioxide nanoparticles can accumulate in the body over time. Health Canada deemed it safe in 2022 but noted concerns. Unlike their European counterparts, Canadian officials did not consider studies performed with titanium dioxide nanoparticles alone. 

Duan et al. administered 125 mg/kg BW or 250 mg/kg BW of anatase TiO₂ (5 nm) intragastrically to mice continuously for 30 days. The exposed mice lost body weight, whereas the relative liver, kidney, spleen and thymus weights increased. Particles seriously affected the haemostasis of the blood and the immune system. The decrease in the immune response could be the result of damage to the spleen, which is the largest immune organ in animals and plays an important role in the immune response. Powel et al. demonstrated that TiO₂ NPs may trigger immune reactions of the intestine after oral intake. They showed that TiO₂ NPs conjugated with bacterial lipopolysaccharide, but not TiO₂ NPs or lipopolysaccharide alone, trigger the immune response in human peripheral blood mononuclear cells and in isolated intestinal tissue. This indicates that TiO₂ NPs may be important mediators in overcoming normal gut-cell hyporesponsiveness to endogenous luminal molecules, which may be particularly relevant to patients with inflammatory bowel disease, which is characterized by an abnormal intestinal permeability.

In terms of titanium concentrate, the market in the Panxi region was quite stable in the first few weeks of the month. The overall state of the titanium ore market was satisfactory, and the price remained stable. The price of 38-grade titanium ore without tax was approximately 1,500-1,530 RMB/MT as of the 13th of January, while it was 2,220-2,260 RMB/MT for 46-grade titanium ore and 2,500-2,550 RMB/MT for 47-grade titanium ore.

One of the key advantages of using anatase titanium dioxide in coatings is its superior UV resistance. This makes it ideal for outdoor applications where coatings are exposed to sunlight and other environmental factors that can degrade the finish over time. Anatase titanium dioxide helps to protect the underlying surface from UV rays, preventing fading and deterioration.

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.”

The presence of so many lithopone factories in China has also led to advancements in production technology and quality control. Chinese manufacturers have invested heavily in research and development to improve the performance of their lithopone products, leading to higher quality and more consistent products on the market. This has helped to cement China's reputation as a leading producer of lithopone on the global stage.

Acknowledgments

A 2022 review on past studies of titanium dioxide and rat lung cancer, for instance, said the original study was under extreme conditions and its effects were not replicated in other animal species. Additionally, the review concluded that the few studies which did directly focus on titanium dioxide's impact on humans did not end up showing any increased cancer risk.