Joined: 16 Mar 2004
|Posted: Thu Feb 01, 2007 10:05 am Post subject: Food fight on a tiny scale
|Food fight on a tiny scale
by Vivienne Parry
Food companies are exploring the use of nanotechnology. It could trigger a GM-style war.
Could nanotechnology be the next food battleground? Five out of ten of the world’s largest food companies, including Heinz, Nestlé, Unilever and Kraft, are aggressively exploring the potential of nanotechnology for better packaging, improved food safety and better nutritional content.
The food industry is moving faster than any other sector to embrace nanotechnology — the manufacture of objects so small that they cannot be seen even with a conventional microscope — and it is estimated that it will be incorporated into $20 billion (£11 billion) worth of food products by 2010.
But do the public want their food engineered? The experience with genetically modified (GM) food would suggest not. Although no nanotech food products are available in Britain, a handful are in the US where there are already demands from lobby groups for “nanohazard” labelling. Could a GM-style nano war be breaking out? Things are moving fast and, next week, many of the issues relating to the use of nanotechnology in food and agriculture are being aired at an Institute of Nanotechnology conference in Amsterdam. The conference will showcase many of the applications of nanotechnologies to the food and healthfood industries in Europe.
Many of the applications of nanotechnology as applied to food are not controversial. The use of “nanofilters” is already ensuring that viruses and bacteria are removed completely from liquids such as milk, improving safety and giving longer shelf life. Equally, there is little controversy over new techniques of attaching nanoscale-sensing devices to food products and packaging, so that the sources of food ingredients can be traced back to origin ; something that food campaigners have long been demanding.
There is also much excitement around the potential of nanotechnology to make food safer. Campylobacter, for example, is a bacterium that does not harm chickens but causes illness in human beings and even death in the vulnerable. A nanoparticle to go into chicken feed is being developed at Clemson University, South Carolina, which would latch on to Campylobacter, ensuring that it is excreted by chickens, so making the bird safer to eat.
And nanoscale silica spheres filled with molecules of a fluorescent dye have been developed to go into meat packaging, where they will detect the presence of the deadly E. coli 0157 bacteria. The surface of the spheres are covered with antibodies that search out and stick to the antigens found on the surface of the E. coli bacteriuma. When contact is made, the spheres literally light up, resulting in a change in packaging colour. Nanomaterials added to PVC films can also prevent spoilage by UV light.
Could nanomaterials migrate from packaging into food? If so, what might their impact be? No one knows yet, although it is the subject of research sponsored by the Food Safety Agency (FSA). So that is one area where future controversy may lie.
But more likely by far to provoke public concern is the interest that food manufacturers are showing in adding nanomaterials directly to food. Because nanotechnology is such a new science, the consequences of them entering the human body is an under-researched area.
Dr Kees Eijkel, of Nano4Vitality, a consortium of small business and researchers based in the Netherlands, and one of the speakers at the forthcoming Amsterdam conference, has concerns. “If you are adding something nanoscale to food, you shouldn’t do it without proper testing and regulation,” he says.
One of the reasons food manufacturers are taking such an interest in nanoscale products is that they can cross cell membranes. Encapsulating nutrients in nanoscale spheres could enhance the biological activity of dietary supplements — or “nutraceuticals” as they are sometimes called — by feeding them directly into cells. A dozen or so dietary supplements of this sort are on the market in the US and have been embraced enthusiastically by health and fitness enthusiasts.
Dr Qasim Chaudhry leads the nanotechnology team at the Central Science Laboratory, an agency of Defra (the Department for Environment, Food and Rural Affairs), and is undertaking the FSA-sponsored research on nanotechnology. He points out that such products may have unanticipated effects, far greater absorption than intended or altered uptake of other nutrients, but little, if anything, is known currently.
Another potential use of nanotechnology directly in food is to use it to improve emulsification, meaning that products such as mayonnaise don’t separate out even if they have a low-fat content. Creating lower-fat products that still have the same mouth-feel and taste as full fat is a big challenge for the food industry. Another area of interest is encapsulation technologies, which allow non-water-soluble products to disperse evenly through water, rather than settle, or which allow liquids to remain clear, rather than turn cloudy when other products are added.
The Woodrow Wilson International Centre at the University of Minnesota has been running the Project on Emerging Nanotechnologies and assessed its anticipated applications in agriculture and food production.
It points out that the food industry is moving faster than almost any other sector to realise the benefits of nanotechnology, while also being reluctant to reveal what is in the development pipeline. This makes it difficult to make an accurate assessment as to whether products are likely to pose a risk.
It could, of course, be that nanomaterials pose no risk at all. After all, human immune systems are configured to deal with nanoparticles in the form of viruses and allergens that we eat and breathe in every day.
Nanoscale salt particles are inhaled when we walk on the beach and sniff the ocean breeze. Nanoparticles are found in combustion products from fires and engines and city dwellers breathe in millions, if not billions, each day on busy streets. As Anthony Seaton, a Professor Emeritus at Aberdeen University and a member of the Royal Society working party on nanotechnology, points out: “Human beings have been exposed to nanoparticles ever since they first started lighting fires.”
Nevertheless, the Royal Society working party has been at pains to point out the dearth of research relating to the impact of nanomaterials on the body and on the environment.
The Project on Emerging Nanotechnologies could, for instance, find no research at all on the impact of nanoparticles on the gut, although this should be of huge interest to the food industry. Also of concern is research revealing that inhaled nanoparticles can later be found in brain tissue, having got through the normal barriers created by blood vessels.
This might be of no importance to human health whatsoever, but it should be noted and appropriate risk assessments instituted on a case-by-case basis.
The Government has recently announced £5 million additional funding for nanotechnology risk assessment. But while the Government claims that it is proceeding with nanotechnology using an evidence-based approach, the truth is that, in such a new area, there is a distinct lack of evidence to go on. The Government needs a more active approach, pushing studies ahead.
The real concern is that when materials are shrunk, they no longer have the same properties. Everything you know about a material in terms of its safety profile has to be torn up. A completely different point of reference may be needed for future safety studies. For instance, weight may no longer be a defining value for toxicity — the more of a toxic substance there is, the greater the risk. Factors such as surface area may be more important for nanomaterials.
Lynn Frewer, a professor of food safety and consumer behaviour at the University of Wageningen in the Netherlands, says consumer views need to be made more of a starting point. “You need to look at what consumers want,” she says. “It has to be voluntary exposure. People want to make their own decisions.” She points to the Starlink controversy in the States, where a brand of GM corn approved only for animal consumption ended up in human food. There was no suggestion that it could harm human health but the frequent use of the phrase “GMO-contaminated” (meaning that it has been in contact with a genetically modified organism) and the realisation that regulation had not prevented unintended mixing was immensely damaging to the food industry.
“If something goes wrong with one nanotechnology, then it goes wrong for all of nanotechnology,” she says.
It’s a sobering thought. It would be a tragedy if the many benefits of nanotechnology were to be denied to the world because the lessons of GM about the introduction of new technology have not yet been learnt.
This story was first posted on 23th October 2006.