Background 
 
For centuries, Silver has been recognised as a natural antibiotic. Understanding that Silver helped to keep spoiled food from making them ill, the Romans ate with Silver knives, forks and spoons, Today, it still sits at the core of most antimicrobial technology, serving as the most effective inhibitor of bacteria, viruses and fungi. That’s why you’ll find it in everyday products, from medical devices to clothing & footwear. 
 
However, a dark cloud is now gathering over the use of Silver in commercial products, with the prospect of it being banned in certain EU countries. That said, it’s not the wholesale use of Silver that’s under scrutiny, but the specific use of Nano Silver (that’s used in over 400 consumer products at the last count), as opposed to Micro Silver. 
 
The issue is compounded by a lack of education and mixed messaging which has resulted in creating a common misconception that all Silver is harmful. This blog aims to present the facts - substantiated with research-based evidence, and to dispel the misinformation surrounding the application of Silver-based antimicrobial solutions in commercial products. 
 
Nano Silver and Micro Silver: 
The Differences 
 
Nano Silver is much smaller in particle size than the Micro Silver that’s used in Micro-Fresh® products* for instance, and as a result it can be absorbed through the skin and major organs in mammals. By contrast, Micro Silver, by nature of being much larger than Nano Silver, sits on the surface and can’t be absorbed. Thus, it’s usually washed away when showering or bathing. 
 
Nano Silver in consumer products that are laundered will slowly rub off at varying rates over time. This will depend on the concentration of Nano Silver in the material, and the strength at which it’s bonded. The industry standard for an antimicrobial solution to be effective in textiles is 50 washes.¹ However, some research suggests that Nano Silver can leach from certain products within the first few washes.² 
 
So what are the implications of this for health and the environment? 
Nano Silver Risks 
 
There is notable research to suggest that Nano Silver could pose a number of risks to human health. Potential harm comes from the fact that because Nano Silver is so minute it can find its way into tiny spaces. Minute also means extensive surface area; the more surface area, the more chemical reactions, some of which can be harmful. 
 
Research has highlighted that Nano Silver may cause mild skin and eye irritations. Of more concern, it points to Silver Nanoparticles being absorbed through the skin, lungs and intestines and into the body’s circulation. As a result, it may subsequently reach the brain, heart, liver, kidneys, testes and spleen. This leads to the area of most concern - that Silver Nanoparticles may actually be genotoxic to mammalian cells, with adverse effects being found in the reproduction of experimental animals. A neurotoxic effect that affects cognitive functions, specifically the impairment of short-term and working memory function, has been linked to exposure to Silver Nanoparticals.³ 
 
Further studies have highlighted that Nano Silver seems to be toxic to particular tissues, especially immature blood cells in bone marrow. Researchers saw the same type of damage in the bone marrow of mice that leads to blood cancers in people. Both mice and humans form blood cells in bone marrow.⁴ 
 
A study in Denmark examined human intestinal cells, which they considered to be the most likely to come into contact with Nano Silver due to food ingestion.⁵ Their conclusion was that Nano Silver leads to the formation of harmful free radicals in cells. A large number of serious diseases are characterised by the overproduction of free radicals in cells. They also saw that there were changes in the form and count of proteins. Despite the fact that the research was conducted on human cells in a laboratory and not on living people, the researchers still concluded that, “This worries us”. 
Micro Silver is Safe 
Like gold, silver is a noble metal, and both are known equally for their low chemical reactivity. 
 
Micro Silver, and its use specifically as an antimicrobial solution, is actually a very recent innovation. In fact, it’s only become commercially available since circa 2005. During this time there’s been extensive research on Silver per se. With Nano Silver, there’s increasing evidence that it can cause potential harm - as we’ve seen earlier in this blog. By contrast, Micro Silver continues to be lauded for being beneficial to health & wellbeing, with antimicrobial, antiviral, anti-irritation, antibacterial and anti-fungal properties. It’s safe, and has never been proven otherwise. 
 
What about the Environment? 
As a closing note it’s important to convey that Micro Silver hasn’t been shown to be harmful to the environment either. The manufacture of Micro Silver doesn’t generate any environmental waste. Once in application, a small amount gets into waterways once washed away, but free silver ions in wastewater are very short lived. On formation they bind with proteins that are present, which neutralises them. The result is that the risk to organisms in the wastewater is eliminated. 
 
The bottom lines is that whilst the debate continues on the potential risks of using Nano Silver in consumer products, Micro Silver remains to be a safe-to-use antibacterial solution for commercial applications. 
 
 
Author: Chris Mellor-Dolman, Head of Marketing & Business Development 
 
References: 
¹ Source: Bernd Nowack of the Swiss Federal Laboratories for Materials Science and Technology 
² Source: Benn TM, Westerhoff P. Nanoparticle Silver Released into Water from Commercially Available Sock Fabric. 
³ Source: Świdwińska-Gajewska AM, Czerczak S. Nanosrebro - szkodliwe skutki działania biologicznego [Nanosilver - Harmful Effects of Biological Activity. 
⁴ Source: P. Kovvuru et al. , Nanotoxicology, 2015 
⁵ Source: Thiago Verano-Braga, Rona Miethling-Graff, Katarzyna Wojdyla, Adelina Rogowska-Wrzesinska, Jonathan R. Brewer, Helmut Erdmann, Frank Kjeldsen. Insights into the Cellular Response Triggered by Silver Nanoparticles Using Quantitative Proteomics. ACS Nano, 2014 
 
*Products marketed under the Micro-Fresh® brand all contain active components with an average out-of-nano-range (1-100nm) particle size dispersion. Hence, all Micro-Fresh® products without exception are micro-structured. 
Share this post:

Leave a comment: 

Our site uses cookies. For more information, see our cookie policy. Accept cookies and close
Reject cookies Manage settings