- Nanotechnology involves structures as small as molecules, with new and unexpected properties that could make them hazardous to health.
- Nanofoods may already be on supermarket shelves without us knowing — and without violating current Australian food regulations.
- CHOICE wants nanofoods better regulated to ensure they are both safe and properly labelled.
Please note: this information was current as of February 2009 but is still a useful guide today.
What is nanotechnology?
Broadly speaking, nanotechnology involves manipulating matter at the nanoscale to create new materials, structures and devices. The nanoscale is usually taken to mean structures ranging in size from one to 100 nanometres, about the size of individual molecules. One nanometre (nm) is a billionth of a metre and to put this in perspective, a human hair is about 80,000nm–100,000nm thick, while a single molecule of the protein haemoglobin (which carries the oxygen in our blood) is about 4nm across.
At this tiny scale, materials can have different properties from their bulk form because of the larger relative surface area (making them potentially more reactive) and new quantum effects that can take over from the usual laws of physics.
Consumer products range from invisible sunscreens (with nanoscale titanium dioxide and zinc oxide) to shirts that don’t stain. In medicine, progress is being made in areas such as disease diagnosis and drug delivery targeted at specific sites in the body (making cancer treatment, for example, potentially more effective), and in other non-domestic situations, nanotechnology is being applied in the fields of environmental protection for water and air purification, pollution detection and harnessing solar energy.
What's the food industry doing?
”Nanofoods” refers to all foods to which manufactured nanoscale food components have been added and/or packaged in materials to which manufactured nanoparticles have been added. Nanotechnology certainly offers exciting possibilities for the future, such as safer food that can be conveniently stored for longer periods without deterioration. Other possibilities include foods fortified with healthy ingredients such as vitamins, antioxidants or omega-3 fats, encapsulated so that they are delivered exactly where they are needed in your body.
Some of the food giants, including Kraft, Nestlé and Unilever, are exploring the use of nanotechnology, but so far keeping very quiet. There are, however, plenty of potential food applications of nanotechnology being openly canvassed.
Food additives Ingredients are processed to form nanostructures or nanotextures to enhance taste, texture and consistency of food. One example of this might be the development of ice-cream with a lower fat content that retains a fatty texture and flavour.
Food processing equipment Knives and chopping boards can be coated with antibacterial silver nanoparticles. These products are already on the market, despite evidence suggesting that nanosilver may be toxic and is already of definite environmental concern. When products treated with nanosilver are washed, nanoparticles are released into waste water treatment facilities and can destroy beneficial bacteria.
Food quality Nanosensors (integrated with packaging) may increase the shelf life of food by detecting spoilage bacteria or the loss of food nutrients, possibly releasing antimicrobials, flavours, colours or nutritional supplements in response.
Food packaging Nanomaterials are already added to packaging to keep food fresher for longer; for example, blocking UV light using nanoscale zinc oxide and antibacterial films that contain silver nanoparticles.
What CHOICE wants
The main issue around regulation is not the small size of nanoparticles as such, rather their novel properties. We’ve always been exposed to naturally occurring nanoparticles, but never before to nanoparticles specifically manufactured to influence food properties. We simply do not yet know enough about how they could affect human health; no one predicted, for example, that carbon nanotubes could cause cancer (see Nanotubes — The new asbestos?).
Regulation definitely warrants a precautionary approach; lack of evidence of harm isn’t evidence of safety. CHOICE would therefore like to see all nanofoods considered as “novel” and as such trigger rigorous case-by-case safety assessments, as required for all novel foods under the Food Standards Code. Specifically, we would like to see the following safeguards:
- A definition of “nano” incorporated into the Food Standards Code.
- Safety assessments carried out by FSANZ to specifically address the new potential risks posed by nanomaterials.
- All food containing manufactured nanoparticles to be specifically labelled.
- All manufactured nanoparticles to be treated as new chemicals and subject to rigorous new safety testing – even those previously used in bulk form. For example, chocolate with nanotitanium dioxide (added to improve its appearance) should not be allowed on the market without undergoing any safety assessment simply because titanium dioxide in its bulk form is a permitted additive.
Without these changes, there’s a very real possibility that nanofoods will appear legitimately on the shelves without having undergone any safety testing — with the potential for serious consequences.