Cornell researchers warn of health hazards from nanoparticles in food and vitamins that are consumed daily by humans. Findings from the scientists show an FDA-approved substance in food additives and vitamins could cause deficiency in the way iron is absorbed in the gut in ways not previously known.
A nanoparticle is a small molecule with at least one dimension less than 100 nm.used to stabilize molecular weight. They're used in food to prevent caking and in vitamins to facilitate absorption. Researchers have been studying the molecules to find ways to deliver cancer drugs directly to tumors. They are added to sunscreens containing titanium dioxide and zinc oxide. Concerns have been raised that the particles applied to the skin can enter the body from inhalation and when applied to the lips, in findings previously reported by Ramona Bates, M.D. for EmaxHealth.
The study, led by Michael Shuler, a professor of Chemical Engineering and chair of Biomedical Engineering at Cornell University, found large doses of polystyrene nanoparticles that are added to food and vitamins affects the absorption of iron in studies conducted on chickens.
The research team used chickens because they absorb iron in the gut in the same way as humans. Chickens are also vulnerable micronutrient deficiencies seen in humans. The results were reported online Feb. 12 in the journal Nature Nanotechnology.
The investigation also included the health hazards from acute and chronic congestion of nanoparticles performed in Petri dishes containing human gut cells. In lab cultures the researchers reported the same results that they found in chickens.
Chronic ingestion of the tiny particles can upset balance in the cell membrane of the gut, leading to over absorption of nutrients as a compensatory mechanism.
Schuler said in a press release, “Nanoparticles are entering our environment in many different ways. We have some assurance that at a gross level they are not harmful, but there may be more subtle effects that we need to worry about.”
Nanotechnology is currently unregulated. Food and vitamin containing nanoparticles don’t require labeling.
The finding shows previously unknown effects from the ingestion of nanoparticles that were not previously known. that have generally been considered safe. The study underscores a potential health hazard found in your vitamins and food from polystyrene nanoparticles that were not previously known.
Nature Nanotchnology: doi:10.1038/nnano.2012.3
"Oral exposure to polystyrene nanoparticles affects iron absorption"
Gretchen J. Mahler, et al.
February 12, 2012
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