In October 2010 the National Organic Standards Board recommended that engineered nanomaterials (ENMs) be prohibited from food products bearing the U.S. Department of Agriculture’s coveted Organic label.1 If the department adopts the recommendation, ENMs will find themselves in the same officially taboo category as genetically modified organisms when it comes to organic foods—nanotechnology-enabled innovations like flavor- and texture- enhancing ingredients and shelf life– extending packaging will be off the menu. Prior to issuing its recommendation, the board received thousands of public comments and petition signatures supporting the ban and virtually none opposing it. Although an official decision could take years, supporters are confident the recommendation will be adopted, and it will go down as one of the first lines drawn in the sand when it comes to the reach of this relatively new and potentially transformative technology in the American marketplace. Nanotechnology-enabled products are quietly proliferating on U.S. store shelves, despite nagging questions about the safety of synthetic nanoparticles and the products that contain them. “[I]n our regulation of food and most consumer products, we don’t implement the precautionary principle. Things go to market before we know whether or not they’re really safe for human beings over the long term,” says Alexis Baden-Mayer, a lawyer with the Organic Consumers Association, an advocacy group, who attended the meeting and campaigned for the ban. Baden-Mayer and other observers perceive a distinct lack of public awareness about how common ENMs are becoming in the market-place, and she hopes discussion among consumers of organic products will help change that. “Consumers don’t know much about nanotechnology, and the first time they may hear about it is now when they learn that the organic regulations are going to prohibit [it],” she says. The International Organization for Standardization defines a nanomaterial as a material with any external dimension between 1 and 100 nm.2 (By comparison, a double strand of DNA is about 2 nm thick.) Nanoparticles, which have been the focus of most nanotoxicology studies to date,3 are one subset of nanomaterials. Nanoparticles include structures of various shapes, such as nanotubes, nanowires, quantum dots, and fullerenes. They also occur naturally in substances like air, smoke, and sea spray, and “incidental” nanoparticles are created during processes such as combustion and food milling, churning, freezing, and homogenization. (Naturally occurring and incidental nanoparticles were not included in the National Organic Standards Board’s recommendation to ban ENMs.) Nanotechnology—the deliberate synthesis and manipulation of nanomaterials—began in the 1980s. Today thousands of ENMs are manufactured in a kaleidoscope of substances, shapes, and sizes for use in a wide range of products and industrial processes that take advantage of their novel physical, thermal, optical, and biological properties. These properties may be determined by the ENM’s chemical composition, size or shape, crystal structure, solubility, adhesion (the force that holds the nanoparticle components together), or surface chemistry, charge, or area.3 Industry analysts have been forecasting “game-changing” advances as a result of nanotechnology in renewable energy, computers, communications, pollution cleanup, agriculture, medicine, and more.4 Clothing, sunscreens, cosmetics, sporting equipment, batteries, food packaging, dietary supplements, and electronics are just a few of the types of nanotechnology-enabled goods in use by U.S. consumers. But safety questions arise around the nanoparticles in some of these products. The novel biological and physical properties of some ENMs pose unique challenges to comprehensive safety research, and investigators are working to figure out just how hazardous they might be to people, wildlife, and the environment. Compared with larger particles, nanoparticles’ tiny size means tissues may take them up more readily. It also can give them an unusual ability to travel throughout the body, including into cells and cell nuclei, and across the placenta and the blood–brain barrier, as demonstrated in rodent studies.5,6 No cases of human illness or death have been definitively attributed to ENMs. However, a number of researchers and consumer and environmental advocates have warned that the abundant unknowns make it necessary to proceed with caution lest we repeat the history of asbestos, polychlorinated biphenyls, the insecticide DDT, and other innovations that seemed valuable when they were introduced, proceeded with little oversight, and ultimately caused major health or environmental problems.
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