Titanium dioxide is used in an enormous range of food products, which can feel jarring when looking at some of its other uses.

However, humans are not exposed to E171 in drinking water at any significant quantity over a long duration, so this potential effect is irrelevant to the human experience. It’s important to understand that a potential hazard is not the same thing as an actual risk. 

But despite all these cries of alarm, five years on from the original study no further testing into the safety of Titanium Dioxide in our food supply

Jinan Yuxing Rutile Titanium Dioxide R-818 is a rutile titanium dioxide pigment coated with inorganic silicon aluminum and organic surface treatment. It has good gloss and hiding power, high weather resistance and good dispersibility.
Scope of application: plastic steel profiles, coil paint, powder coatings, rubber, masterbatch, etc.

Lithopone

Lithopone in natural and synthetic elastomers 

Mexican researchers sought to evaluate the effects of E171 across a span of conditions in mice, including its influence on behavior, along with the effects on the colon and liver. The research, published in 2020 in the journal Food and Chemical Toxicology, showed that E171 promoted anxiety and induced adenomas, or noncancerous tumors, in the colon. They also found that E171 heightened goblet cells hypertrophy and hyperplasia, which is typically seen in asthma patients and triggered by smoking or external pollutants and toxins. They also noted mucins overexpression in the mice, which can be linked to cancer cell formation. 

For people in occupational settings that increase the risk of titanium dioxide exposure, taking protective measures is helpful. This may include wearing protective equipment, such as respirators, and using ventilation systems.

Research has shown that, when ingested as a food additive, titanium dioxide and its nanoparticles can impact, alter, and/or damage important protective bacteria in the gut, along with the metabolic pathways of gut bacteria.

In an early study Jani et al. administred rutile TiO₂ (500 nm) as a 0.1 ml of 2.5 % w/v suspension (12.5 mg/kg BW) to female Sprague Dawley rats, by oral gavage daily for 10 days and detected presence of particles in all the major gut associated lymphoid tissue as well as in distant organs such as the liver, spleen, lung and peritoneal tissue, but not in heart and kidney. The distribution and toxicity of nano- (25 nm, 80 nm) and submicron-sized (155 nm) TiO₂ particles were evaluated in mice administered a large, single, oral dosing (5 g/kg BW) by gavage. In the animals that were sacrificed two weeks later, ICP-MS analysis showed that the particles were retained mainly in liver, spleen, kidney, and lung tissues, indicating that they can be transported to other tissues and organs after uptake by the gastrointestinal tract. Interestingly, although an extremely high dose was administrated, no acute toxicity was observed. In groups exposed to 80 nm and 155 nm particles, histopathological changes were observed in the liver, kidney and in the brain. The biochemical serum parameters also indicated liver, kidney and cardiovascular damage and were higher in mice treated with nano-sized (25 or 80 nm) TiO₂ compared to submicron-sized (155 nm) TiO₂. However, the main weaknesses of this study are the use of extremely high single dose and insufficient characterisation of the particles.

BaSO4+4CO→BaS+4CO2

The European Food Safety Authority updated its safety assessment of the mineral in March 2020, stating that titanium dioxide can no longer be considered safe as a food additive. This was due to evidence of potentially harmful effects after consumption of the mineral, which may accumulate in the body over time.