Get Ready For Nanotech Food

NANOSCALE MATERIALS have the potential to improve the taste, color, flavor, texture, and consistency of food. Innovators in the food industry are using them to encapsulate dietary supplements to increase the absorption and bioavailability of nutrients. And they're adding these new materials to food packaging to create a stronger mechanical barrier, kill microbes, detect chemical and microbial contamination, and facilitate the traceability of foods.

Despite the promises of nanotechnology for food applications, a growing number of people are beginning to question whether government oversight and consumer awareness are sufficient to prevent the kind of public backlash that occurred with genetically modified foods and food irradiation.

At a daylong public meeting in September, the Food & Drug Administration called upon stakeholders to help the agency better understand concerns related to the safety and effectiveness of nanoscale materials in FDA-regulated products, including food, food packaging, and dietary supplements.

In July 2007, FDA released its Nanotechnology Task Force Report, which addressed the scientific and regulatory challenges associated with nanoscale materials (C&EN, July 30, 2007, page 44). The report recommended that FDA develop guidance for manufacturers and researchers who are creating nanotech-based products that fall under FDA's jurisdiction. The September meeting was part of FDA's effort to get information to help the agency establish that guidance.

"Nanoscale materials present challenges similar to those that we've come across with other emerging technologies in the past. But the fact that size influences efficacy and safety can complicate the challenge," Richard A. Canady, senior science policy analyst in FDA's Office of Science & Health Coordination, noted at the meeting.

Among the concerns raised by FDA in the 2007 report and discussed at the September meeting are the adequacy of current approaches for testing the safety, efficacy, and quality of nanotech products; the lack of standards for characterizing nanoscale materials; and the need for better detection and measurement tools to understand how nanoscale materials interact with biological systems. FDA is collaborating with other agencies such as the National Institute of Standards & Technology, the National Cancer Institute's Nanotechnology Characterization Laboratory, the National Toxicology Program, and the Organization for Economic Cooperation & Development to address these issues, Canady noted.

THUS FAR, FDA has approached nanotechnology on a case-by-case basis, Mitchell A. Cheeseman, deputy director of FDA's Office of Food Additive Safety, told the audience during a meeting breakout session focused on nanotech food additives and dietary supplements. The agency is looking for help in identifying which nanotech food ingredients or packaging components raise unique safety concerns, Cheeseman said. In addition, he said, FDA wants input related to "circumstances under which a product's regulatory status might change due to the presence of nanoscale materials."

For example, FDA is looking for feedback on whether a substance that is designated by the agency as generally recognized as safe (GRAS) at the macroscale should also be considered GRAS at the nanoscale and therefore be allowed to forgo safety testing and premarket approval. Several meeting participants stepped up to offer FDA input on this issue.

"What this really boils down to is acknowledging that a nanoscale particle that has novel properties should be deemed a new substance for purposes of safety evaluation," said Michael R. Taylor, a research professor at the George Washington University School of Public Health & Health Services and a former FDA staff lawyer and assistant to the FDA commissioner. It is incumbent on FDA to provide guidance on this issue, he emphasized.

Consumer advocacy groups pushed FDA to abandon GRAS status for all nanoscale materials. "We urge FDA to recognize that nanoscale particles exhibit novel properties and behaviors compared to their larger counterparts and raise unique safety concerns," said Michael Hansen, senior staff scientist at Consumers Union, the nonprofit organization most known for its publication Consumer Reports. Hansen recommended that FDA require separate safety assessments on all nanoscale materials before they are used in any food or food packaging applications.

Friends of the Earth (FoE), an environmental group, took it a step further and recommended that FDA establish a moratorium on nanoscale materials in all food products until specific safety laws are on the books. Major players in the food industry are investing in nanotech R&D, and many of them already have nanotech-based products on the market, warned Ian Illuminato, FoE's health and environment campaigner. Examples of such products include a nutritional supplement drink for children that contains iron nanoparticles, McDonald's hamburger containers, Cadbury chocolate bar wrappers, and Miller Lite beer bottles, he noted. Illuminato estimated that the nanotech food industry would be worth $6 billion by 2010.

The Project on Emerging Nanotechnologies, a nonprofit partnership between the Woodrow Wilson International Center for Scholars and the Pew Charitable Trusts, keeps an inventory of consumer products that contain nanotechnology. To date, the database contains more than 800 products that were self-identified by the manufacturers as containing nanotechnology.

A search of this database finds four products that fall under the food and beverage category. They include a nanotea that claims to increase selenium supplement function by 10 times; a cooking oil with nanosized droplets, or micelles, that inhibit cholesterol from entering the bloodstream; plastic beer bottles lined with a nanotech nylon material that scavenges oxygen to keep the beer fresher longer; and a chocolate shake with "NanoClusters" that "offer enhanced flavor without the need for excess sugar."

Despite the growing number of nanotech food products on the market, consumers aren't aware of them. The public comment part of the food additives session at the FDA meeting was surprisingly silent; only a handful of preregistered individuals spoke out.

The lack of significant public input was not a surprise to social scientists who say that the public does not know that nanotech food products already are on store shelves. "Consumers have no information about nanotechnology in food," said Christine M. Bruhn, an expert on consumer attitudes about food and director of the Center for Consumer Research at the University of California, Davis. "They do not know about the benefits or the risks," she told C&EN.

ONE REASON consumers don't have information on food-related nanotech is simple: Food and food packaging do not require labels to indicate that nanoscale materials have been added. Consumers, therefore, have no way of knowing which products contain nanotechnology. To remedy this situation, FoE and other advocacy groups are pushing FDA to require labeling of nanotech products. "Consumers want to make the choice. No labeling takes this freedom away from them," Illuminato emphasized.

In addition to labeling, critics are calling for more public education about nanotech. After all, most observers say, the potential benefits of nanotechnology in food applications are huge, but they also acknowledge that for the technology to be successful, the public has to be comfortable with it.

To get a feel for what consumers are willing to accept, Michael Siegrist, professor of risk analysis at the Institute for Environmental Decisions at the Swiss Federal Institute of Technology, Zurich, surveyed 337 randomly chosen people in Switzerland about the risks of nanotechnology in various food applications. The results were published in July in the journal Appetite (2008, 51, 283).

Siegrist found that acceptance for nanotechnology in food packaging was relatively high. However, consumers were considerably more critical of nanotechnology-based ingredients in food. Even so, the potential for migration of nanoscale materials from food packaging did not emerge in the survey as a big concern.

Migration from food packaging was also discussed at the FDA meeting. According to Raymond David, manager of toxicology at BASF, the public has little to worry about. "Exposure from food packaging can be controlled based on the size of the nanoparticles," he said, explaining that the larger the particle, the less likely it is to be released. Nanoparticles can also be impregnated into a matrix rather than just applied to a surface to make them less likely to migrate, he added.

Many people at the meeting called for standard methods for testing the safety of nanoscale materials, similar to those under development by the newly formed International Alliance for NanoEHS Harmonization (C&EN, Sept. 15, page 5). The EHS in the name stands for environment, health, and safety. "FDA needs to provide guidance on testing methods. Divergent testing protocols will lead to limited comparability of tests and lower confidence in nanotechnology," said Jo Anne Shatkin, managing director of CLF Ventures, a nonprofit affiliate of the environmental advocacy group Conservation Law Foundation.

"Existing frameworks for assessing risks and establishing safety levels need to be updated" to address nanoscale materials, Shatkin stressed. She recommended a life-cycle approach—one that takes into account cumulative exposures—to assess the risks of nanotechnology.

Others, such as BASF's David, said that current risk assessment approaches should be adequate for nanoscale materials. What are needed, he said, are new in vitro tools for predicting how nanoparticles move in the body. The shelf life and stability of products that contain nanoscale materials should also be examined, he suggested.

MEANWHILE, as U.S. manufacturers move forward with nanotechnology in food products, countries in Europe are taking a more cautious approach. For instance, the Food Safety Authority of Ireland recently reported that more research on the risks of nanotechnology is needed before nanotech food products should be allowed in the Irish market.

A decade ago, industry's bravado in bringing genetically modified foods into the market elicited emotional public outcries with GM products derided as poorly tested "frankenfoods" that should not have a place in the diet. That is why those entering the nanotech food arena expect public attitudes to be mixed. Nearly everyone at the FDA meeting agreed that transparency and broad public engagement are needed to provide the knowledge that presumably will preempt consumer fear. Otherwise, they said, nanotech food products won't have much of a chance for success.