Responding to the EC's consultation document containing a definition of ‘particulate nanomaterials’ focusing on materials in the 1-100 nanometre range, the IFST said the size at which the properties of a material could abruptly change varied widely according to the material and the properties in question.
“There is thus concern over the selection of the single upper size boundary. For biological materials the measurement of size and size distribution can also be dependent on the sample preparation method and the method used to size the samples.”
Meanwhile, the way a product was formulated might also affect its classification, noted the IFST. For example, if individual stabilised nanocrystals were sold as ingredients for colouring foods, they would be classified as nanomaterials, because they are tiny.
However, were another ingredient formulated by agglomerating the same nanocrystals into bigger groups, their particle size meant that it would not be classified as a nanomaterial, even though processing it could lead to a free dispersion of its constituent nanoparticles in a food or drink, said the IFST.
“The final product would be the same but the classification, labelling and regulation might be very different.”
Proteins, carbs, lipids not included in definition
On the plus side, the definition proposed by the EC should exclude ‘natural’ food molecules such as proteins, carbohydrates and lipids, which many observers feared might get caught up in any new labelling regime, added the IFST.
Focusing on ‘particulate nanomaterials’ was also important because it should exclude most of the nanostructures introduced into foods through “rational or empirical processing”, it added.
“However the definition of particulate nanomaterials would include particulate nano-delivery systems such as nanoemulsions, nanoparticulate carriers, nanomicelles, nanocrystals, protein–based nanotubes and also certain metal and metal oxide nanoparticles.”
Regulatory minefield
Currently, the only legal definition for nanomaterials in the EU is enshrined in the Cosmetics Regulation (EC 1223/2009), which defines nanomaterials (for labelling purposes) as “insoluble or biopersistent and intentionally manufactured… with one or more external dimensions or an internal structure on the scale of 1-100-nanometres”.
A second definition – which focuses on “intentionally-produced materials in the order of 100-nanometres or less” - is included in the latest draft of the revised Novel Food Regulation, which also calls for nanomaterials to be labelled on food packaging, something many manufacturers oppose.
Nano labels
However, agreeing on a legal definition that satisfies food manufacturers, regulators, enforcement bodies and consumers is proving very challenging.
Food manufacturers and retailers are concerned that too broad a definition could prompt widespread 'nano' labelling and alarm consumers unnecessarily.
In a recent debate on nanotechnology hosted by the Food Standards Agency (FSA), Unilever R&D director, regulatory affairs, consumer confidence and sustainability, Charles-Francois Gaudefroy said: “We support [nano] labelling provisions where they provide meaningful specific information to consumers.”
Former FSA chairman Lord Krebs also expressed concerns about the value of ‘nano labels’ in a recent debate in the House of Lords: “We did not see an advantage in labelling foods that contain nanomaterials, as we could not see what consumers would do with such information when shopping.”