Iron phosphate nanoparticles for food fortification: Biological effects in rats and human cell lines

Abstract

Nanotechnology offers new opportunities for providing health benefits in foods. Food fortification with iron phosphate nanoparticles (FePO₄ NPs) is a promising new approach to reducing iron deficiency because FePO₄ NPs combine high bioavailability with superior sensory performance in difficult to fortify foods. However, their safety remains largely untested. We fed rats for 90 days diets containing FePO₄ NPs at doses at which iron sulfate (FeSO₄), a commonly used food fortificant, has been shown to induce adverse effects. Feeding did not result in signs of toxicity, including oxidative stress, organ damage, excess iron accumulation in organs or histological changes. These safety data were corroborated by evidence that NPs were taken up by human gastrointestinal cell lines without reducing cell viability or inducing oxidative stress. Our findings suggest FePO₄ NPs appear to be as safe for ingestion as FeSO₄.

Keywords:

• Iron phosphate nanoparticles
• food fortification
• in vitro
• in vivo
• nanotoxicology

Acknowledgements

The authors would like to thank F. Krumeich and S. Handschin (ETH Zurich) for performing TEM on some particles and cells, V. Galetti (ETH Zurich) for support with statistical analysis, C. Zeder, P. Rast, L. Posavec, C. Wellenzohn, R. Govender (ETH Zurich), G. Pellegrini, E.M. Schraner, S. Kitz (UZH-Vetsuisse) and Albert Schuler (PSI) for their technical assistance, Evonik for providing the silica particles and Prof. S. Pratsinis (ETH Zurich) for helpful discussions.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.

Additional information

Funding

This research was funded by the Swiss National Science Foundation [406440_141610] and [CRSII3_136247/2].