Migration of engineered nanoparticles from polymer packaging to food - a physicochemical view

A physicochemical perspective on the potential migration of engineered nanoparticles (ENPs) from packaging to food is presented, based on evaluation of the average distance travelled by ENPs in the polymer matrix. The Study has taken into account physicochemical properties of both ENPs and packaging polymers. From the properties, some general characteristics underpinning ENP migration can be predicted. The results indicate that any detectable migration of ENPs from packaging to food will take place in the case of very small ENPs with a radius in the order of 1 nm, from polymer matrices that have a relatively low dynamic viscosity, and that do not interact with the ENPs. These conditions are likely to be met in the case of nanocomposites of silver with polyolefines (LDPE, HDPE, PP). It can also be predicted that there will not be any appreciable migration in the case of bigger ENPs, that are bound in polymer matrices with a relatively high dynamic viscosity such as polystyrene and polyethylene terephtalate.