Nav: Home

Do kitchen items shed antimicrobial nanoparticles after use?

November 08, 2018

Because of their antimicrobial and antifungal properties, silver nanoparticles measuring between one and 100 nanometers (billionth of a meter) in size, are being incorporated outside the United States into a variety of kitchen products known as food contact materials (FCMs). Among the nanosilver-infused FCMs now on the market overseas are spatulas, baby mugs, storage containers and cutting boards. However, the use of these items raises concerns that the nanoparticles in them will migrate into foods and the environment, and in turn, whether this poses risks to human health.

To address these issues, government bodies around the world have published guidance documents, set policies and considered regulations. These have been largely based on research that examined nanosilver release from new, unused consumer products or laboratory surrogates, but not actual FCMs during and after use. In a new paper, scientists from the U.S. Food and Drug Administration (FDA), the National Institute of Standards and Technology (NIST) and the U.S. Consumer Product Safety Commission (CPSC) describe how they simulated knife motion, washing and scratching on nanosilver-containing cutting boards to see if consumer use practices affect nanoparticle release.

Using a test method developed at NIST, five different "use scenarios"--each simulating a different type and level of wear commonly seen with human use--were conducted by moving three abrasive surfaces back and forth across samples of nanosilver-enabled cutting board material.

The researchers hope their test method will help regulatory bodies identify if any safety or health risks exist from silver nanoparticles in food contact materials, and if so, find ways to deal with them appropriately before they are approved for sale in the United States.

"A custom-designed razor blade replicated knife cuts, a piece of scrubbing pad mimicked normal dishwashing conditions and a tungsten carbide burr imitated scratching by metal utensils," said NIST physical scientist Keana C.K. Scott, one of the authors on the paper published in the journal Food Additives and Contaminants: Part A. "The washing and scratching scenarios were done at one or two levels of abrasion; for example, 500 and 5,000 cycles for the scratching simulation."

After the abrasion runs, the NIST researchers used sticky tape to see if loose silver nanoparticles were present and could be removed from the worn cutting-board samples. Scanning electron microscopy (SEM) at NIST and inductively coupled plasma mass spectrometry (an incredibly sensitive method for detecting metal ions) at the FDA showed that bits of cutting board polymer were released by abrasion and that some of these contained embedded silver. However, free silver nanoparticles were not found on the SEM-examined tape.

FDA scientists also determined how much, if any, silver ions and intact silver nanoparticles would migrate away from cutting boards when exposed to water and acetic acid. They found that the concentrations of ionic and particulate silver found in both solutions were very low. In fact, there was no discernable difference in the silver migration observed from the new and unused nanosilver-enabled cutting boards compared with the ones that were cut, washed or scratched.

Based on their findings, the NIST and FDA researchers suggested that future studies should examine whether a combination of use scenarios would increase the amount of silver ions or nanoparticles released. For example, they said, perhaps washing the cutting board after scratching would have a different impact.

"Now that we've shown that the migration evaluation method works, it can be used to help answer this and other questions about what happens when people use FCMs with nanoparticles," said NIST research chemist David Goodwin, another author on the paper. "In turn, those findings should be valuable for the bodies that must determine any health or safety risks."
-end-
Paper: S. Addo Ntim, S. Norris, D.G. Goodwin, J. Breffke, K.C.K. Scott, L. Sung, T.A. Thomas and G.O. Noonan. Effects of Consumer Use Practices on Nanosilver Release from Commercially Available Food Contact Materials. Food Additives and Contaminants: Part A, October 23, 2018. DOI: https://doi.org/10.1080/19440049.2018.1529437.

National Institute of Standards and Technology (NIST)

Related Nanoparticles Articles:

Chemists perform surgery on nanoparticles
A team of chemists led by Carnegie Mellon's Rongchao Jin has for the first time conducted site-specific surgery on a nanoparticle.
Nanoparticles remain unpredictable
The way that nanoparticles behave in the environment is extremely complex.
Gold standards for nanoparticles
KAUST researchers reveal how small organic 'citrate' ions can stabilize gold nanoparticles, assisting research on the structures' potential.
Lipid nanoparticles for gene therapy
Twenty-five years have passed since the publication of the first work on solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) as a system for delivering drugs.
Nanoparticles hitchhiking their way along strands of hair
In shampoo ads, hair always looks like a shiny, smooth surface.
Better contrast agents based on nanoparticles
Scientists at the University of Basel have developed nanoparticles which can serve as efficient contrast agents for magnetic resonance imaging.
Gentle cancer treatment using nanoparticles works
Cancer treatments based on laser irridation of tiny nanoparticles that are injected directly into the cancer tumor are working and can destroy the cancer from within.
Radiation-guided nanoparticles zero in on metastatic cancer
Zap a tumor with radiation to trigger expression of a molecule, then attack that molecule with a drug-loaded nanoparticle.
Nanoparticles can grow in cubic shape
Use of nanoparticles in many applications, e.g. for catalysis, relies on the surface area of the particles.
Nanoparticles deliver anticancer cluster bombs
Scientists have devised a triple-stage 'cluster bomb' system for delivering the chemotherapy drug cisplatin, via tiny nanoparticles designed to break up when they reach a tumor.

Related Nanoparticles Reading:

Nanoparticles: From Theory to Application
by Günter Schmid (Editor)

Nanoparticles - Nanocomposites – Nanomaterials: An Introduction for Beginners
by Wiley-VCH

Computational Nanotechnology: Modeling and Applications with MATLAB® (Nano and Energy)
by Sarhan M. Musa (Editor)

Bio-Nanoparticles: Biosynthesis and Sustainable Biotechnological Implications
by Om V. Singh (Editor)

Gold Nanoparticles for Physics, Chemistry and Biology
by Catherine Louis (Author), Catherine Louis (Editor), Olivier Pluchery (Editor)

Magnetic Nanoparticles
by Sergey P. Gubin (Editor)

Engineered Nanoparticles: Structure, Properties and Mechanisms of Toxicity
by Ashok K Singh (Author)

Magnetic Nanoparticles: From Fabrication to Clinical Applications
by CRC Press

Nanoparticle Superheroes Defeat Evil Microbes
by Anna Rutkowski (Author)

Nanoparticles Synthesis, Stabillization, Passivation and Functionalization (ACS Symposium Series)
by Ramanathan Nagarajan (Editor), T. Alan Hatton (Editor)

Best Science Podcasts 2018

We have hand picked the best science podcasts for 2018. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Unintended Consequences
Human innovation has transformed the way we live, often for the better. But as our technologies grow more powerful, so do their consequences. This hour, TED speakers explore technology's dark side. Guests include writer and artist James Bridle, historians Yuval Noah Harari and Edward Tenner, internet security strategist Yasmin Green, and journalist Kashmir Hill.
Now Playing: Science for the People

#499 Technology, Work and The Future (Rebroadcast)
This week, we're thinking about how rapidly advancing technology will change our future, our work, and our well-being. We speak to Richard and Daniel Susskind about their book "The Future of Professions: How Technology Will Transform the Work of Human Experts" about the impacts technology may have on professional work. And Nicholas Agar comes on to talk about his book "The Sceptical Optimist" and the ways new technologies will affect our perceptions and well-being.