Title : Titanium dioxide nanoparticles (E171) in food: A review of functional uses and toxicological concerns
Abstract:
The use of titanium dioxide nanoparticles (TiO₂, food additive E171) in the food industry has raised growing concern due to their potential effects on human health. Commonly employed as a white pigment to enhance the visual appearance of confectionery, dairy products, and sauces, TiO₂ is partly present in the nanoscale form, which profoundly alters its physicochemical and biological properties. Recent studies indicate that repeated oral exposure to nano-TiO₂ can induce oxidative stress, genotoxic damage, as well as disruptions of the gut microbiota and epithelial barrier. Its bioaccumulation capacity in certain organs (liver, kidneys, spleen) further reinforces concerns about long-term systemic effects. These findings led the European Food Safety Authority (EFSA) in 2021 to conclude that no safe intake level could be established for TiO₂ as a food additive, a decision followed by its subsequent ban in the European Union. This regulatory evolution highlights the urgent need for comprehensive assessment of food nanomaterials and the development of safer alternatives, such as natural colorants or biopolymers. The case of TiO₂ illustrates the challenges posed by emerging toxic substances in food and underscores the importance of integrating nanotoxicology into food risk assessment.
Keywords: Titanium dioxide (TiO₂), Nanoparticles, Food additive, Food safety, Toxicological risk assessment.
