Regulatory safety assessment of nanoparticles for the food chain in Europe

Background: The risk assessment of small particles (including nanoparticles) in products used in the food chain in the EU falls within the remit of the European Food Safety Authority (EFSA) and has been under thorough scientific considerations for over a decade. Now that more experience is gained with evaluating novel foods, food contact materials, food/feed additives and pesticides, the outlines for regulatory safety assessments and data requirements are established. Scope and approach: This paper reviews the principles underlying safety testing of small particles, referring to two recently published EFSA guidance documents. Examples and observations from assessing existing materials are provided to facilitate to a wider readership adequate implementation of the regulatory requirements. Main findings and conclusions: The starting point for safety testing is the physicochemical characterisation of the pristine material, being an engineered nanomaterial, a nanostructured material or a conventional material that contains a fraction of small particles that may retain properties at the nanoscale. Key parameters and threshold values for establishing the presence of small particles, the techniques and methods for characterisation in complex matrices, as well as approaches for dietary exposure assessment are outlined. Where there is the likelihood of small particles remaining after gastrointestinal digestion, hazard identification and hazard characterisation are required with special provisions. In particular, certain nano-specific considerations are highlighted that have to be considered during toxicological testing with the aim to demonstrate consumer safety of products to be used in the food chain in Europe.