News Section: Environment
E Investigates the Nanoparticles in Our Food
The November/December 2012 issue of E - The Environmental Magazine (now posted at: www.emagazine.com) features a package of articles devoted to the increasing presence of nanoparticles in our food supply.
On the surface, nanoparticles seem to offer many potential benefits: By adding them to foods and food packaging, they can help deliver nutrients, act as thickening agents, enhance taste or flavor or ensure longer freshness of food. But these tiny microscopic versions of silver, zinc, titanium dioxide and other metals and nutrients, largely because of their microscopic size, may cause adverse health impacts.
The problem is that scientists are still determining the health and environmental impacts of these tiny particles, even as industry is forging ahead. Each of these nanoparticles has a distinct way of reacting with the human body, and there is little research to assure us that ingesting these microscopic materials is safe. Even more alarming, there is no information readily available to consumers alerting them as to which products contain nanoparticles, and the U.S. Food and Drug Administration (FDA) does not keep records on the matter.
E Magazine asked a spokesperson at the FDA: "Where are the nanomaterials most often found within food products?" He answered: "FDA does not maintain a list of food products that contain nanomaterials, so we cannot reliably answer this question."
Foods Containing Nano
Despite lack of a comprehensive listing, we know that nanoparticles are in the food supply, and have been for at least a decade. Recent research found that foods with caramelized sugar, including bread and corn flakes, contain carbon nanoparticles. Many nutritional supplements -- or "nanoceuticals" -- come equipped with copper, silver or iron nanoparticles. Nanoparticles can be used to purify water, as anti-caking and gelatin-forming agents, and in packaging to protect against UV light, prevent the growth of microbes or detect contamination. And titanium dioxide lends white pigment to most toothpastes and many processed foods, including Mentos, Trident and Dentyne gum, M&Ms, Betty Crocker Whipped Cream Frosting, Jello Banana Cream Pudding, Vanilla Milkshake Pop Tarts and Nestle Original Coffee Creamer.
Nanoparticles also enter the food supply unintentionally. Biosolids from wastewater treatment plants that are used as fertilizer contains zinc oxide nanoparticles from sunscreens and other products. Research has found that soybeans grown with this fertilizer take up the nanoparticles in their leaves, stems and beans.
And nanoparticles in food wrappings, used to protect the food from contamination, could be contaminating our bodies instead. "We know that there's nanosilver in food wrapping and food packaging," says Jennifer Sass, a senior scientist with the Natural Resources Defense Council (NRDC). "That nanosilver releases ions, so those ions could be getting into the food. The ions are toxic, they are the antimicrobial part of the silver."
Because companies are not required to label their products as containing nanomaterials, and only do so voluntarily, it is primarily the companies that make supplements, who wish to tout their copper, silver or iron nanoparticles, that give consumers a clue as to what's inside.
What's the Worry?
Nanoparticles, whether in consumer goods or in the food supply, are being treated as though they are equivalent to their larger counterparts. In other words, the government considers silver and nano-silver to be essentially the same. But their tiny size means they function quite differently within the body, the full ramifications of which are still coming to light. In 2011, researchers discovered that silver nanoparticles, when inhaled, cause lung toxicity or inflammation in exposed mice.
Similarly, inhaled copper nanoparticles increased the risk of pulmonary infections in mice. Carbon nanotubes, used in super-strong plastics and for computer chips, have presented a particular worry, when research found in 2008 that the particles can damage lungs in a similar fashion as asbestos, which the particles resemble in shape and size.
Ingesting nanoparticles may cause more subtle health problems than inhalation. The particles, due to their small size, can pass into the bloodstream and then accumulate in organs. Once there, writes the American Society of Safety Engineers, they can "disrupt and impair biological, structural and metabolic processes and weaken the immune system."
And recent research discovered that when chickens consumed large quantities of polystyrene nanoparticles, approved for human consumption, they blocked the animals' ability to absorb iron. Cornell researcher Gretchen Mahler, one of the authors of the study, says: "The nanomaterials that are being developed all have very different reactivity with human tissues. This means that you can't apply results with one type of nanoparticle to all other nanoparticles -- you have to test them all individually."
Brita Belli is an editor for E - The Environmental Magazine. To subscribe: www.emagazine.com/subscribe. Free Trial Issue: www.emagazine.com/trial.