Safety Assessment Considerations When Testing Food Ingredients or Food Related Nanomaterials

Nanomaterials (NM) are substances that have at least one dimension in the nanoscale (1-100 nm). In the food industry, nanomaterials can have a multitude of uses. Nanomaterials can be used as food ingredients or dietary supplements that aim to increase absorption, or targeted nutrient delivery. Nanomaterials may also be used to enhance the physical and sensorial properties of a food product, or as a manufacturing aid.

The FDA recommends assessing the safety of nanomaterials on a case-by-case basis, stating that, “there are no food substances intentionally engineered at the nanometer scale for which there are currently enough safety data to consider their use as GRAS” (Amenta, 2015).[1] A change in manufacturing practices to modify a GRAS substance to the nanoscale requires testing to assert safety-in-use of the nanosized substance by a panel of qualified experts.

Considerations in the safety assessment of NMs arise from their physico-chemical properties. Their small size allows them to have a wider distribution, retention and closer interaction with biological systems than larger particles. Due to this small size, NMs may be retained in many cells and organs to a greater extent than larger particles of similar food ingredients. These factors impact systemic exposure and, therefore the toxicological profile of NMs, potentially resulting in new and unique safety concerns not shared with their macro-brethren.

A safety assessment must be initiated with a pre-biological physico-chemical characterization. In addition to describing the chemical composition by providing an applicable chemical formula, defining a source (when a food substance is of natural biological origin), and determining impurities and contaminants profile, physical properties are important to assess including, but not limited to  melting and boiling points, specific gravity, refractive index, optical rotation, pH, solubility, reactivity, particle size, size distribution, surface area, surface charge, agglomeration potential, chromatographic, spectroscopic and spectrometric characteristics (U.S. Food and Drug Administration (2014) Guidance for Industry: Assessing the Effects of Significant Manufacturing Process Changes, Inclu