Nanotechnology and food: what should we worry about?

The potential use of nanotechnologies in food gives rise to two distinct types of issue. There’s a narrow issue, about whether engineered nanoparticles are entering the food chain, and if so, whether this leads to any dangers to human health. But there’s also a rather broader set of issues that arise from the fact that we are now able to alter the nanoscale structure of food with much greater control and purpose than before. Of course, we should balance the positive benefits of such interventions against any potential risks. But this assessment will necessarily take place in a context which goes well beyond the technical issues that surround nanotechnology, and takes in people’s deeply held instincts about our proper relationship with our food.

The key worry about engineered nanoparticles was that, because approvals for food additives didn’t typically specify size, a nanoscale version of an existing additive, which might have new problems of toxicity, might slip through the regulatory net. In Europe, at least, this potential problem seems to have been headed off by last year’s amendment of the Novel Food Regulation, making clear that any food containing or consisting of engineered nanoparticles will need mandatory pre-market assessment and approval. There are still issues relating to the precise definition of a nanomaterial to be sorted out here; nanomaterials created from natural food substances will be a particular point of contention. Nonetheless, there is progress here – one welcome and concrete sign of this is that it seems no longer possible to buy nano-silver “food supplements” from health food shops, following a recent ruling by the European Food Safety Authority.

What about the broader applications of nanotechnology in food? In my evidence to the House of Lords inquiry, I picked out three key potential areas of food nanotechnology:

• Food science at the nanoscale. This is about using a combination of fairly conventional food processing techniques supported by the use of nanoscale analytical techniques to achieve desirable properties. A major driver here will be the use of sophisticated food structuring to achieve palatable products with low fat contents.
• Encapsulating ingredients and additives. The encapsulation of flavours and aromas at the microscale to protect delicate molecules and enable their triggered or otherwise controlled release is already widespread, and it is possible that decreasing the lengthscale of these systems to the nanoscale might be advantageous in some cases. We are also likely to see a range of “nutriceutical” molecules come into more general use.
• Water dispersible preparations of fat-soluble ingredients. Many food ingredients are fat-soluble; as a way of incorporating these in food and drink without fat manufacturers have developed stable colloidal dispersions of these materials in water, with particle sizes in the range of hundreds of nanometers. For example, the substance lycopene, which is familiar as the molecule that makes tomatoes red and which is believed to offer substantial health benefits, is marketed in this form by the German company BASF.

The key issues here aren’t so much about safety. For some, there will be an instinctive recoiling from the idea of manipulating our food at such a fundamental level, while others will regard these methods as no different in principle from more traditional cooking and food processing. Some people will argue that, rather than using nanotechnology to make food less fattening and more nutritious, we should just eat more fresh fruit and vegetables. Countering this, others will say that the reality of the way people live now dictates that pre-prepared and processed food will be increasingly important in people’s diets, so food manufacturers have a moral obligation to use available technology to make their products as healthy as possible. As is the case for many debates that centre on nanotechnology, it will be values as much as safety that people argue about.