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Scientists say nanotechnology can help make food manufacturing, processing and transportation more secure by using nanosensors to protect against pathogens and contaminants.

Since nanotechnology operates on the same scale as a virus or disease-infecting particle, it has the potential for very early detection and eradication of pathogens. One possibility is that by operating at such a tiny scale, nanotechnology can activate a “smart” treatment system long before macro symptoms – those that would actually do damage to foods or humans – appear.

One development in this area is the application of nanotechnology to create anti-microbial containers. Through nano-technology embedded in packaging material, these containers can prevent food microbial contamination, and thus facilitate better food preservation, storage and distribution.

Professor Paul Takhistov at the Department of Food Science at Rutgers University is currently designing a packing material that incorporates nano-based biosensors. This packaging uses nano-sensors to detect pathogens and trigger the release of anti-microbials if needed.

“It will allow more functionality for food and packaging,” he says. “[Packaging] could change its properties depending on the properties of the item being packaged.”

Nanotechnology can also help with food security by monitoring products as they move through the supply chain. For example, nano-sized sensors embedded in packaging material could record the historical environmental records of a particular product, noting if it had been exposed to heat or cold – factors that might affect its contents.

Along with detecting environmental factors, nano-sized sensors can assist in monitoring contaminants in food products. One company specializing in this kind of application is NanoSensors Inc. Based in California, NanoSensors is developing a biosensor to detect E. coli and salmonella in foods. CEO Dr. Ted Wong explains the unit’s operation.

“We put on the sensor a host molecule that attracts E. coli, and when there’s an interaction between the two, it creates an electrical charge that is detected [by the sensor],” he said.

The sensor is composed of a disposable housing unit in which it’s mounted, and a separate data acquisition unit. The sensor transmits the electrical signals to the data unit, which then converts them and displays results. The sensor is currently undergoing third party testing, says Wong, that will be completed by the end of the year. He does not know when the product will be commercially available.

“We’re trying to make it a very user-friendly interface, and we hope to get that answer [of whether it is] from our third party testing,” he says.

However, along with the benefits of food safety aspects gained from nano-technology, some researchers point to safety concerns generated by the technology. Since it has only been around for a few decades, researchers are still unsure of long-term effects, and some question whether appropriate tools to measure these effects are available yet. In a report entitled “Down on the Farm: The Impact of Nano-Scale Technologies on Food and Agriculture,” released in November 2004, the Ottawa-based non-governmental organization ETC Group argued that nano-technology must be carefully regulated and government, industry and researchers must engage in a wide discussion of the role of converging nanoscale technologies in food and agriculture. Without public discussion, several commentators have noted that problems of public perception, similar to those experience by the GMO industry a few years ago, may develop as consumers become anxious due to a lack of lack dialogue and information.

“Is it safe to add nanoparticles to foods? The short answer to the question is ‘no one knows for sure’,” ETC Group’s report states. “The issue has yet to be confronted head on by either regulators or the scientific communities.”

The report notes that while ETC Group isn’t in the position to assess the safety of nano-scale food additives, they “want to highlight the regulatory vacuum, where size does not matter and nano-scale formulations do not trigger any special regulatory scrutiny.”

In October 2006, Dr. Qasim Chaudhry, senior scientist at the Central Science Laboratory in the U.K. was quoted as saying that the rapid proliferation of nanotechnology has led to its ever-increasing application in products including foods and drinks, but this widespread use is “largely untested in terms of effects on human health and the environment.”

Nanotechnology is too recent a field to have any regulations applied to it. While organizations like the Environmental Protection Agency and consumer NGOs like the ETC Group, Corporate Watch and Friends of the Earth have all raised concerns, at present there are no regulations on the use of the technology in Europe, the U.S. or Canada.

Dexter Johnson, conference director at U.K.-based research group Cientifica, points out that while his organization’s recent report examined regulation issues, as of 2006 no government had developed a regulatory regime that specifically addressed items at the nano-scale.

“There may be regulations regarding chemical substances, such as TiO₂ in any food ingredient [that is] safe for consumption, but these regulations do not take into account the size of the substance,” he writes in an e-mail interview. “In other words, it may be determined that a certain portion of TiO₂ in any food ingredient is safe for consumption, but we do not know, nor is it regulated, if that TiO₂ is delivered in nanoscale form whether it then poses any health risk.”

Takhistov agrees that the regulation of nanotechnology is a very complicated issue. However, he points to the existence of nanoparticles in nature – in the carbon after a forest fire, for example – and says he hasn’t seen any scientific evidence that nano-sized materials are more toxic than other materials. As well, he notes that the total amount of nano-material being produced is only a few tons or a couple hundred kilos a year. But he still outlines the need for government regulation.

“To ensure proper acceptance of the new technology by the public we need some regulation,” he says. “It’s very difficult to say which way it could go… If all materials pass through standard testing [I can’t see any danger].”