Are nanoparticles a threat to public health? Two recent studies reveal unexpected downstream effects of these new and little-researched ingredients
Many in the food and supplement industry are excited about the potential of nanotechnology: to make food colorings more stable, to distribute taste more seamlessly so the amount of fat or salt in processed foods may be reduced, to make nano-sized nutrients more bioavailable, and much more.
But for me, two studies published this summer raise serious concern about the silent and growing use of these little-researched manufactured nanomaterials (MNMs). And unfortunately—with a back-story that’s eerily familiar to that of GMOs—MNMs have been fast-tracked into our foods and food packaging, cosmetics and sunscreens, and many other products without the courtesy of a label that informs consumers what’s in the products we buy, use and consume daily.
This month, scientists at UC Santa Barbara's Bren School of Environmental Science & Management announced research showing that zinc oxide, a common sunscreen ingredient, and cerium oxide, a fuel ingredient, when present in soil as MNMs, affect the yield and quality of soybean plants.
(Outside the lab, these particles end up in agricultural soil when they concentrate in biosolids—a basically unregulated wastewater treatment end product that’s used as fertilizer. Cerium oxide MNMs also enter air and soil via exhaust or leaked fuel.)
In the study, soybean plants grown in soil containing zinc oxide MNMs bioaccumulated zinc throughout the plant, including the beans, affecting food quality, said Senior Author, Professor Barbara Holden. In soil with cerium oxide MNMs, plant growth was stunted due to changes in the root nodules, where symbiotic bacteria normally help naturally fertilize the plant. Holden theorized that more synthetic fertilizers may be needed where MNMs accumulate in soil.
In the other study, published in the journal Nanomedicine in June, scientists linked exposure to carbon MNMs and other new types of airborne pollutants with the development of autoimmune diseases such as rheumatoid arthritis. In two parallel studies, mice and human cells that line airway passages were exposed to carbon MNMs, causing identical responses—changes in amino acids in the body which can trigger autoimmune processes.
In April, the FDA released sets of proposed rules for companies working with nanotechnology—and the USDA awarded a $400,000 grant to a University of Massachusetts Amherst food scientist to study how to make natural nanoparticles for delivering oil-soluble vitamins and other nutrients in food products.
If nano-engineered food substances have new properties, the FDA report says, "it may be necessary to further examine the effects of a change in these properties, including any effects on the bioavailability of the food substance and its transport across the gut.” An extremely vaguely worded and flaccid recommendation follows, stating that in such cases, “studies to support the safety of food substances… should have been appropriately validated for these materials.”
I don’t know about you, but I am not at all reassured. In my conversations with health experts, I hear more and more about novel proteins crossing from the gut into the bloodstream and contributing to obesity, allergies and sensitivities, and other modern-day health woes. Chances are, you are already eating foods and using products with MNMs. Referencing a nano-silver antibacterial toothbrush he saw at Whole Foods, Natural Vitality president Ken Whitman says, "These tiny particles can permeate the skin and who knows how many other layers. Would nano particles penetrate the blood-brain barrier? Where else can they travel?"
I am dismayed to learn that yet another Pandora’s Box (read GMOs) has been opened without adequate prior study, without safety protocols in place, and without informing consumers. I want to know what’s in the food and supplements I give my family—and what effect these new particles may have on our soil, air and water.
What do you think about nanotechnology? Share your thoughts in the comments.
And for more information about nanotechnology in food, check out www.understandingnano.com.