Food, Global Health 3 min

Titanium dioxide: evidence of its toxicity

The use of titanium dioxide (E171) has just been banned as a food additive following a change in the regulation of the European Commission published on 18 January 2022, with a 6-month period for its implementation. This decision follows on from the expert report of the European Food Safety Authority (EFSA) concluding in an opinion published on 6 May 2021 that E171 could no longer be considered safe when used as a food additive. This opinion was based in particular on pioneering research conducted by an INRAE team (Toxalim Occitanie-Toulouse). Below is an overview of INRAE research on the toxic effects of E171.

Published on 06 May 2021 (date.last_update 21 January 2022)

illustration Titanium dioxide: evidence of its toxicity
© INRAE, Toxalim

What is titanium dioxide?

It’s a food additive widely used throughout the world for its opacifying and colouring properties (white pigment). Better known in Europe as E171, the sale of food products containing this additive has been suspended in France since January 1st, 2020, for precautionary reasons[1] and its ban has just been extended to Europe in January 2022.

Studies by INRAE scientists in 2017 and 2020, first on the immunotoxic potential of E171 and its role in promoting precancerous lesions in the intestine then on titanium dioxide (TiO2) nanoparticles crossing the placental barrier, provided the scientific evidence necessary for these measures. In 2021, EFSA updated its previous evaluation published in 2016 on E171, highlighting data gaps in its previous assessment which had asserted the absence of a health risk.  EFSA now considers that E171 is no longer safe when used as a food additive, an opinion which has led to a change in regulations at the European level.

Looking back on our key research results:

E 171 crosses the placental barrier in humans
Working in collaboration with the Laboratoire national de métrologie et d’éssais (LNE), the Groupe de Physique des Matériaux (CNRS/INSA Rouen/Université de Rouen-Normandie), Toulouse University Hospital, Picardie-Jules Verne University and the National Veterinary School in Toulouse, INRAE scientists have pursued their work in humans and have supplied proof that TiO2 nanoparticles present in the additive E171 can cross the placenta and reach the foetal environment. Their results, published on 7 October 2021 in Particle and Fibre Toxicology, alert on the importance of evaluating the risk of exposure of pregnant women to these nanoparticles.

 2021 press release

E171 crosses the intestinal barrier in animals
INRAE researchers and their partners have studied the effects of oral exposure to titanium dioxide, an additive (E171) commonly used in foodstuffs, especially confectionary. They have shown for the first time that nanoparticles of E171 cross the intestinal barrier in animals and reach other parts of the body. Immune system disorders linked to the absorption of the nanoscale fraction of E171 particles were observed. The researchers also showed that chronic oral exposure to the additive spontaneously induced preneoplastic lesions in the colon, a non-malignant stage of carcinogenesis, in 40% of exposed animals. Moreover, E171 was found to accelerate the development of lesions previously induced for experimental purposes. While the findings show that the additive plays a role in initiating and promoting the early stages of colorectal carcinogenesis, they cannot be extrapolated to humans or more advanced stages of the disease. The findings were published in the 20 January 2017 issue of Scientific Reports.

2017 press release

In 2018, researchers showed that titanium dioxide did not weaken the intestinal mucusa in animals. (2018 press release in French).
In 2020, the main absorption pathways of TiO2 in the intestine were identified by the same teams (DOI: 10.1186/s12989-020-00357-z).

1 Application of the French Law of 30 October 2018 on the balance of trade relations in the agricultural and food sector and healthy, sustainable, and accessible food for all (EGalim Law). This measure applies to food products sold in France, for a period of one year, potentially renewable. This precautionary principle does not apply to non-food products. https://www.legifrance.gouv.fr/jorf/id/JORFTEXT000038410047?r=v1pKGxVbGN (in French)

 

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Food, Global Health

Nanoparticles of titanium dioxide: E171 crosses the placental barrier

PRESS RELEASE - What is titanium dioxide? It is an important food additive widely used throughout the world for its opacifying and colouring properties (white pigment). Better known in Europe as E171, the sale of food products containing this additive has been suspended in France since January 1st, 2020, for precautionary reasons[1]. Studies[2] by INRAE scientists in 2017 had provided the scientific proof necessary to underpin this limited measure, introduced for a period of one year potentially renewable. Working in collaboration with the Laboratoire national de métrologie et d’éssais (LNE), the Groupe de Physique des Matériaux (CNRS/INSA Rouen/Université de Rouen-Normandie), Toulouse University Hospital, Picardie-Jules Verne University and the National Veterinary School in Toulouse, the same scientists continued their work in humans and now supplied proof that the titanium dioxide nanoparticles present in E171 can cross the placenta and reach the foetal environment. Their results, published on October 7th in Particle and Fibre Toxicology, alert on the importance of evaluating the risk of exposure of pregnant women to these nanoparticles.

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PRESS RELEASE - Researchers from INRA and their partners have studied the effects of oral exposure to titanium dioxide, an additive (E171) commonly used in foodstuffs, especially confectionary. They have shown for the first time that E171 crosses the intestinal barrier in animals and reaches other parts of the body. Immune system disorders linked to the absorption of the nanoscale fraction of E171 particles were observed. The researchers also showed that chronic oral exposure to the additive spontaneously induced preneoplastic lesions in the colon, a non-malignant stage of carcinogenesis, in 40% of exposed animals. Moreover, E171 was found to accelerate the development of lesions previously induced for experimental purposes. While the findings show that the additive plays a role in initiating and promoting the early stages of colorectal carcinogenesis, they cannot be extrapolated to humans or more advanced stages of the disease. The findings were published in the 20 January 2017 issue of Scientific Reports.

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