Titanium dioxide (E171): should you worry?

Daniel Platteau

In short: titanium dioxide (E171) is a white colouring that has been banned from food and food supplements in the European Union since 7 August 2022. Europe did not prove that it is dangerous to humans. It concluded that it could no longer rule out that it damages DNA, and that a purely decorative colouring did not justify that doubt. It is still allowed in medicines (about 91,000 in Europe), for lack of an equally effective substitute, and in cosmetics, including toothpaste. Outside Europe (United States, United Kingdom, Canada, Australia), the authorities have kept it. For you: no need to panic about what you ate before 2022, never stop a medicine for this reason, and only be wary of sweets and supplements imported from outside the EU.

Updated on 16 October 2026.

This article is part of our series on food additives. For the basics (E numbers, acceptable daily intake, who decides), first read our introductory article.

What is titanium dioxide?

Titanium dioxide (chemical formula TiO2) is a white mineral, very opaque and very stable. It is the most widely used white pigment in the world: it is found in paint, paper, plastics, sunscreens (where it filters UV), toothpaste, medicines and, until 2022, in our food.

In food, it carried the number E171. It had no nutritional or preservative purpose: it only made a product whiter or shinier. It was mainly found in:

• sweets, sugared almonds, chewing gum and cake decorations;
• icings, toppings and some white sauces;
• some soups, pastries and biscuits;
• the coating of food supplements in capsules or tablets.

On a cosmetic label, it appears as CI 77891 or "titanium dioxide".

The real issue: particle size

E171 is not a uniform powder. Part of its grains measure less than 100 nanometres (a nanometre is a millionth of a millimetre): these are nanoparticles. At this size, a substance may behave differently: it can cross some of the body's barriers more easily and react more with cells, depending on its shape, its coating and the dose. This "nano" fraction is what concentrated the concerns.

Why Europe banned it

A warning from France

It all started with a study by France's National Institute for Agricultural Research (now INRAE), published in January 2017 in Scientific Reports (Bettini et al., 2017). Rats were given E171 in their drinking water for 100 days, at 10 mg per kilo of body weight per day. Result: 4 of the 11 exposed rats (nearly 40%) developed precancerous lesions in the colon, against none of the 12 control rats, and previously induced lesions progressed faster. The researchers also observed disturbances of the gut immune system.

The authors were careful to point out that these results could not be transposed to humans. But they were enough for France to suspend E171 in food from 1 January 2020.

EFSA's 2021 opinion

The European Food Safety Authority (EFSA) re-examined all the studies. In its opinion of 6 May 2021, it concluded that E171 can no longer be considered safe as a food additive (EFSA FAF Panel, 2021). Its reasons:

• E171 is very poorly absorbed by the gut, but the absorbed particles can accumulate in the body;
• some studies show that TiO2 particles can cause DNA strand breaks and chromosome damage;
• the data neither confirm nor rule out this risk, for lack of sufficiently complete studies covering all particle sizes.

The key word is genotoxicity: a substance's ability to damage genetic material. For a genotoxic substance, no risk-free dose can be set. EFSA was therefore unable to set an acceptable daily intake (ADI). On that basis, the European Commission and the Member States decided to withdraw its authorisation.

The timeline of the ban

• 14 January 2022: the Commission adopts Regulation (EU) 2022/63, which removes E171 from the list of authorised additives.
• 7 February 2022: entry into force, with a six-month transition period.
• 7 August 2022: end of the transition. Foods made before that date could stay on the shelves until their best-before date.

The ban applies to all foods, including food supplements, throughout the Union, and therefore in Belgium. The Belgian food safety agency (AFSCA/FAVV) enforces it.

What the studies show

In animals

Since the 2017 study, many experiments in mice and rats have observed effects of TiO2 nanoparticles on the gut: inflammation, a leakier gut wall, changes to the microbiota, less effective intestinal stem cells. Other animal studies have reported effects on the placenta and on foetal development.

These results raise questions, but they have two limitations. First, many studies use laboratory nanoparticles, not E171 as it was sold, sometimes at high doses. Second, an effect in rodents is not necessarily found in humans.

In humans

In 2020, an INRAE team analysed 22 placentas from volunteer mothers and 18 samples of newborns' first stools (meconium). It found titanium in all the placentas and in half of the meconium samples, partly in nanoparticle form. In an isolated placenta perfused in the laboratory, it showed that E171 particles could pass from the mother's side to the foetus's side in this laboratory model (Guillard et al., 2020).

This is evidence of exposure, not evidence of an effect: the study did not measure any consequence for the babies' health. The titanium found could also come from sources other than food (toothpaste, medicines, air).

To date, no study has shown that people who ate more E171 had more cancers or bowel diseases. Such a study would be very hard to carry out anyway: nobody knows how much E171 they ate.

Why other countries did not ban it

Europe has remained almost alone. With the same studies, several agencies reached a different conclusion:

• United Kingdom: the Committee on Toxicity (COT) concluded in December 2024 that a risk from current dietary intakes was unlikely, and that genotoxicity was probably not a concern. E171 remains authorised in Great Britain (COT, 2024).
• Canada: in July 2022, Health Canada concluded that there was "no conclusive scientific evidence" that food-grade titanium dioxide is a concern for health (Health Canada, 2022).
• Australia and New Zealand: the FSANZ agency considers that there is no evidence that dietary exposure is a concern (FSANZ, 2025).
• United States: the Food and Drug Administration (FDA) still allows it, up to 1% of the food's weight. Five organisations, including the Center for Science in the Public Interest (CSPI), asked for its withdrawal in March 2023; by the end of 2025, the FDA had not yet replied (CSPI, 2025). In California, titanium dioxide was removed from the 2023 and 2024 additive bills under pressure from industry.

How can this disagreement be explained? It is not that EFSA saw evidence the others ignored. It is a difference of rule:

• Europe applies the precautionary principle: if safety is no longer demonstrated, the authorisation goes, all the more quickly when the additive is not essential;
• the other agencies rather require evidence of a real risk at the doses consumed before withdrawing an already authorised product.

Both approaches can be defended. Above all, the difference shows that the question is not settled scientifically.

What about medicines?

Titanium dioxide remains authorised in medicines. It is found in about 91,000 human medicines in Europe, mainly in tablet coatings and capsules. It plays a real role there: it makes the tablet opaque, protects the active ingredient from light, and helps tell medicines apart.

The 2022 regulation provided for a review. The European Medicines Agency (EMA) issued two opinions:

• in 2024, it found the available substitutes less effective, and considered that a rapid withdrawal risked causing shortages;
• in March 2025, it considered, on the basis of limited data, that the cancer risk linked to medicines was negligible.

In early August 2025, the European Commission confirmed that titanium dioxide should remain authorised in medicines (Nutritional Outlook, 2025). The amounts involved are also much smaller than those that could be swallowed with sweets.

What about toothpaste and cosmetics?

Titanium dioxide remains authorised in cosmetics, under the name CI 77891: toothpaste, lipstick, foundation, sunscreen.

• On the skin: no study shows a risk, as TiO2 does not cross healthy skin.
• By mouth (toothpaste, lipstick): in 2024, the European Scientific Committee on Consumer Safety (SCCS) examined 84 grades of TiO2. For almost all of them, it could not rule out a risk to DNA, for lack of sufficient data. It notes that the amount swallowed with a cosmetic is much smaller than with the former E171, and calls for studies, particularly on toothpaste used every day (RIVM, 2024). Some grades could eventually be banned if manufacturers do not provide these data.
• By inhalation (powders, sprays): this is the most worrying route in animals. The International Agency for Research on Cancer (IARC) classifies TiO2 as "possibly carcinogenic" (group 2B) for this reason. Nano forms are already restricted in products that can be breathed in. However, the European classification of powdered TiO2 as "carcinogenic by inhalation" was annulled by the EU courts; the Court of Justice confirmed this on 1 August 2025. This annulment concerns the classification method: it does not prove that breathing in TiO2 powder is risk-free.

For children who swallow their toothpaste, the right habit does not change: a small amount (a grain of rice before age 3, a pea-sized amount after), and teach them to spit.

What to do in practice?

What you ate before 2022: no reason to worry. No effect has been demonstrated in humans, and any risk would depend on the dose and the duration.

Today, in Belgium: food sold legally must no longer contain E171. The points to watch are:

• sweets and products imported from outside the EU (specialist shops, online purchases from the United States or the United Kingdom), where E171 is still allowed;
• food supplements bought on websites outside the EU;
• very white or pearly cake decorations of doubtful origin.

Read the label: "E171", "titanium dioxide" or "dioxyde de titane". European manufacturers have mainly replaced it with calcium carbonate (E170), rice starch or other opacifiers.

Medicines: do not change anything without medical advice. For long-term treatment, you can ask your pharmacist whether a version without titanium dioxide exists.

Toothpaste and cosmetics: if you want to reduce your exposure, choose products without CI 77891. This is not a health emergency, it is a precautionary choice. Prefer sun creams and lotions to sprays and powders, which can be breathed in.

Pregnant women: passage into the placenta has been shown, effects have not. No reason for alarm, but one more reason to avoid imported products that contain it.

Going further: why science hesitates

Three difficulties explain why E171 is still debated ten years after the first warnings.

E171 is not a single substance. Grain size, crystal form and coating vary from one manufacturer to another. A study done with laboratory nanoparticles does not necessarily say much about commercial E171, and vice versa. That is why the SCCS had to examine 84 different grades.

Genotoxicity is hard to prove or to rule out. Standard tests were designed for dissolved molecules, not for particles. Depending on the method, the same TiO2 can appear genotoxic or not. EFSA judged the results too uncertain to conclude; the British, Canadian and Australian agencies found the negative results more reliable.

Actual exposure is poorly known. How much E171 did a child eat? What share of the particles crossed the gut? Where did they accumulate? These figures remain estimates.

What the ban changed above all is the question being asked. For a useful additive (a preservative that protects against botulism, for example), the risk is weighed against the benefit. For a colouring that only serves appearance, the slightest serious doubt is enough to tip the balance.

In the next articles in the series: sweeteners, then nitrites, emulsifiers, glutamate and colourings.

Test yourself

Disclaimer

This article is a summary of information. It does not replace the advice of a doctor or pharmacist, especially before changing a treatment.

Sources

Bettini, S., Boutet-Robinet, E., Cartier, C., Coméra, C., Gaultier, E., Dupuy, J., Naud, N., Taché, S., Grysan, P., Reguer, S., Thieriet, N., Réfrégiers, M., Thiaudière, D., Cravedi, J.-P., Carrière, M., Audinot, J.-N., Pierre, F. H., Guzylack-Piriou, L., … Houdeau, E. (2017). Food-grade TiO2 impairs intestinal and systemic immune homeostasis, initiates preneoplastic lesions and promotes aberrant crypt development in the rat colon. Scientific Reports, 7, 40373. https://doi.org/10.1038/srep40373

Center for Science in the Public Interest. (2025, December 10). Titanium dioxide hiding in holiday treats, dairy, and more. CSPI. https://www.cspi.org/cspi-news/titanium-dioxide-hiding-holiday-treats-dairy-and-more

Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment. (2024). COT statement on the safety of titanium dioxide (E171) as a food additive: Lay summary. Food Standards Agency. https://cot.food.gov.uk/COT%20Statement%20on%20the%20Safety%20of%20Titanium%20dioxide%20(E171)%20as%20a%20Food%20Additive%20-%20Lay%20Summary

EFSA Panel on Food Additives and Flavourings. (2021). Safety assessment of titanium dioxide (E171) as a food additive. EFSA Journal, 19(5), e06585. https://doi.org/10.2903/j.efsa.2021.6585

European Commission. (2022). Commission Regulation (EU) 2022/63 of 14 January 2022 amending Annexes II and III to Regulation (EC) No 1333/2008 as regards the food additive titanium dioxide (E 171). EUR-Lex. https://eur-lex.europa.eu/eli/reg/2022/63/oj

Food Standards Australia New Zealand. (2025). Review of titanium dioxide as a food additive. FSANZ. https://www.foodstandards.gov.au/consumer/foodtech/Review-of-titanium-dioxide-as-a-food-additive

Guillard, A., Gaultier, E., Cartier, C., Devoille, L., Noireaux, J., Chevalier, L., Morin, M., Grandin, F., Lacroix, M. Z., Coméra, C., Cazanave, A., de Place, A., Gayrard, V., Bach, V., Chardon, K., Bekhti, N., Adel-Patient, K., Vayssière, C., Fisicaro, P., … Houdeau, E. (2020). Basal Ti level in the human placenta and meconium and evidence of a materno-foetal transfer of food-grade TiO2 nanoparticles in an ex vivo placental perfusion model. Particle and Fibre Toxicology, 17, 51. https://doi.org/10.1186/s12989-020-00381-z

Health Canada. (2022, July 14). Titanium dioxide (TiO2) as a food additive: Current science report. Government of Canada. https://www.canada.ca/en/health-canada/services/food-nutrition/reports-publications/titanium-dioxide-food-additive-science-report.html

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Nutritional Outlook. (2025, August 15). European Commission confirms titanium dioxide use in medicines following EMA review. https://www.nutritionaloutlook.com/view/european-commission-confirms-titanium-dioxide-use-in-medicines-following-ema-review

RIVM. (2024, October 3). Genotoxicity of titanium dioxide in cosmetics cannot be excluded. RIVM on Advanced Materials. https://www.rivm.nl/en/weblog/genotoxicity-of-titanium-dioxide-in-cosmetics-cannot-be-excluded

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