Titanium dioxide is found in pretty much all makeup & sunscreen.

And studies have long shown that products applied to the skin end up in the bloodstream within half an hour. With penetration rates depending on where they are applied. Absorption rates for your face & scalp are 5-10 times higher than on other parts of our body (Hotchkiss 1994).

Not to mention that in 2005, the Environmental Working Group published a combination of two studies that found toxic chemicals in the umbilical cord blood of newborn babies born in the U.S. They screened for more than 400 chemicals, and an astounding 287 toxins were detected within the umbilical cord blood of these newborns. Of these 287 chemicals, 217 were neurotoxins, and 208 are known to damage growth development or cause birth defects.

Fig. 1. Weight loss (%) of vitaminB2@P25TiO₂NPs.

Digestive System Exposure 

Alterations in gut microbiota

What titanium dioxide is really emblematic of ... is the failure of FDA to look back at these old decisions and ask whether its decisions that were made in this case ... 56 years ago (in the 1966 approval) still hold up, he said.

After conducting a review of all the relevant available scientific evidence, EFSA concluded that a concern for genotoxicity of TiO₂ particles cannot be ruled out. Based on this concern, EFSA’s experts no longer consider titanium dioxide safe when used as a food additive. This means that an Acceptable Daily Intake (ADI ) cannot be established for E171.

Titanium dioxide (TiO₂) is considered as an inert and safe material and has been used in many applications for decades. However, with the development of nanotechnologies TiO₂ nanoparticles, with numerous novel and useful properties, are increasingly manufactured and used. Therefore increased human and environmental exposure can be expected, which has put TiO₂ nanoparticles under toxicological scrutiny. Mechanistic toxicological studies show that TiO₂ nanoparticles predominantly cause adverse effects via induction of oxidative stress resulting in cell damage, genotoxicity, inflammation, immune response etc. The extent and type of damage strongly depends on physical and chemical characteristics of TiO₂ nanoparticles, which govern their bioavailability and reactivity. Based on the experimental evidence from animal inhalation studies TiO₂ nanoparticles are classified as “possible carcinogenic to humans” by the International Agency for Research on Cancer and as occupational carcinogen by the National Institute for Occupational Safety and Health. The studies on dermal exposure to TiO₂ nanoparticles, which is in humans substantial through the use of sunscreens, generally indicate negligible transdermal penetration; however data are needed on long-term exposure and potential adverse effects of photo-oxidation products. Although TiO₂ is permitted as an additive (E171) in food and pharmaceutical products we do not have reliable data on its absorption, distribution, excretion and toxicity on oral exposure. TiO₂ may also enter environment, and while it exerts low acute toxicity to aquatic organisms, upon long-term exposure it induces a range of sub-lethal effects.

Algaecidal effect of Lithopon: After 5 years of exposure to weathering in Alpen (Lower Rhine)  

≤0.6