Because of their small size, nanoparticles may have unique physical and chemical properties. These properties may cause them to interact with living systems differently than larger materials with the same chemical composition (also known as bulk materials).

Some consumer advocacy groups and health agencies — particularly, those at the Environmental Working Group — have been pushing federal officers at the Food and Drug Administration (FDA) to reconsider their existing rules on the additive, which is commonly found in processed snacks and sweets.