Challenges for evaluating the safety of food nanomaterials
Evaluating the safety of nanomaterials in foods presents multiple challenges, according to speakers at the fifth IFT International Food Nanoscience Conference. Attracting nearly 100 attendees, the one-day conference took place on Saturday, July 17, just prior to opening of the IFT Annual Meeting & Food Expo®.
One of the challenges is determining the validity and objectivity of nanoparticle safety studies. To address this challenge, Bernadene Magnuson, Ph.D., Senior Scientific & Regulatory Consultant, Cantox Health Sciences International, announced a two-step approach utilizing the Klimisch scoring system (K1–K4 reliability) and particle characterization properties to communicate the strengths, weaknesses, and limitations of various studies examining the toxicity of food and food-related nanomaterials.
Both Magnuson and Paul C. Howard, Ph.D., National Center for Toxicology Research, U.S. Food and Drug Administration, discussed the importance of particle characterization, which affects biological activity. Critical particle parameters include agglomeration, aggregation, chemical composition, crystal structure/crystallinity, particle size/size distribution, purity, shape, surface area, surface charge, and surface chemistry (including composition and reactivity).
Another challenge is that nanoparticles interfere with detection methods and analytical techniques. Stefan Weigel, Ph.D., Senior Project Manager, RIKILT – Institute of Food Safety, Wageningen University & Research Center, discussed analytical tools for the detection (presence) and characterization (identity and concentration) of nanoparticles in complex food matrices. “Electron microscopy is a suitable tool for the imaging of nanoparticles in complex matrices, and HDC-ICP-MS is a viable technique for the analysis of inorganic nanoparticles, such as silver,” noted Weigel. Sample preparation is also key.
In January 2010, a European collaborative research project was launched to validate analytical methods for engineered nanoparticles in food matrixes, explained Weigel. The project will run for three years and will examine inorganic nanoparticles (e.g., silver, silica, titanium dioxide) and organic nanoparticles such as encapsulates. It will also develop reference materials for engineered nanoparticles in food. The project will launch a Web site—www.nanolyse.eu—in August 2010.