E171: one less poison on our plates

At the origin of the ban on the food additive E171 - a study by INRA in collaboration with LIST

Titanium dioxide, or E171, is used to give a white colour to many foods, whether they are sweets, baked goods, sandwich spreads, soups, sauces, salad dressings or food supplements. On 14 January, the European Commission adopted a ban on the use of titanium dioxide as a food additive.

From a local impact to a European impact

This decision by the European Commission is based on solid scientific evidence: it is based on a scientific opinion from the European Food Safety Authority, which follows the results of a research project carried out by the National Research Institute for Agriculture, Food and the Environment (INRAE, ex INRA), in collaboration with LIST.

In 2017, researchers from INRAE ​​and their partners, including LIST, published the results of their study on the effects of oral exposure to titanium dioxide. They showed for the first time that chronic exposure to E171 causes precancerous lesions in the colon of rats. The nanoparticles of this additive are also able to cross the intestinal wall and enter the bloodstream, and therefore impact the liver.

Following this study, France took the decision in 2019 to remove this additive with a potential carcinogenic risk, from our plates. The European Commission has just followed suit with a decision which will apply after a transitional period of six months. This means that from this summer, this additive can no longer be added to food products, throughout the European Union.

To carry out this study, INRAE ​​notably called on LIST's cutting-edge skills in toxicology microanalysis. The toxicology study coupled with ion microscopy technology, a very high-resolution imaging system, carried out at LIST is not only unique in Luxembourg but also very little developed in the world.

Nanoparticles detected thanks to the expertise of LIST

Nanoparticles have established themselves in our daily lives, in pharmaceuticals, agri-food, construction or textiles, and raise many questions. Specialists agree on one point: with nanomaterials, it is impossible to generalise. The health risks differ depending on the chemical nature of the nanoparticles, their size or even their shape. They must therefore be examined on a case-by-case basis before asserting that a nanoparticle is toxic.

LIST has the expertise and tools to meet this challenge since it has notably created, within the framework of the npSCOPE project, a new integrated and optimised instrument to provide a complete physico-chemical characterisation of nanoparticles both in their primitive form, and incorporated in complex matrices such as biological tissues.

Therefore, LIST is currently studying the effects of perfluorinated substances, or PFAS, these "eternal" and ubiquitous pollutants: although prohibited, these substances are found in many everyday consumer products and remain in the environment and in our bodies for a very long time. Food consumption is the main source of exposure to PFAS. The digestive system is therefore the first physical and biological barrier against these new environmental pollutants, and at the same time their first target. Surprisingly, their effects on the intestinal wall remain largely unknown to this day. Their study is currently the subject of the FLUO-GUT project, piloted at LIST by researcher Jean-Nicolas Audinot: "These projects, whether for the analysis of the E171 additive, the assembly of the npSCOPE or the analysis of PFAS, have enabled us to set up models that can be adapted to other types of studies related to health risks. Our future challenge is to study microplastics, which pollute the oceans and disrupt the entire food chain, until they end up on our plates.”

The stakes are high, and LIST intends to take up this challenge, which reinforces its societal mission of developing high-impact technologies to improve the quality of life and build a more sustainable economy.

_{^{Photo credit: Heather Ford}}