Are silver nanoparticles harmful

Are Silver Nanoparticles Safe? Consequences for health, the environment and microbial resistance

Because of its antibacterial properties, silver is often used in medical products and consumer goods because, unlike other bactericides, it has a broader spectrum of activity and is less toxic. More and more products are using silver as nanoparticles because it has better bactericidal activity and therefore smaller amounts can be used. Are these nanoparticles safe for your health and for the environment? Could microorganisms become resistant to the effects of silver?

What are “nanoparticles”?

So-called nanoparticles are materials and components that have at least one dimension in the size range 1 - 100 nanometers (a nanometer is a billionth of a meter). Due to their size, these materials can particularly interact with human body cells and tissues. Assessing the potential impact of nanoparticles on human health is an ongoing process.

What types of consumer goods contain nanosilver?

Food packaging, dietary supplements (if not expressly approved, currently not approved in the EU), textiles, electronics, household appliances, cosmetics, medical devices, water disinfectants and room sprays are just a few examples of products that contain nanosilver. At present, products containing nano-silver are difficult to find because they are sold under numerous brand names. In addition, current labeling regulations - with a few exceptions - do not require an explicit listing of nanomaterials as a component.

What are the health effects?

The toxicity of silver, including silver nanoparticles, is generally low to humans. Skin contact with clothing containing silver is one of the most important ways in which these nanoparticles are exposed. In general, consumer products release only small amounts of silver that do not have significant health consequences.

What are the effects on the environment?

Silver in the environment comes from its many uses in industry, medicine, water disinfection and in consumer products. Silver as a nanoparticle makes up only a fraction of the total amount of silver that gets into the environment. However, silver in this form could be more easily absorbed by some genera, which is a potential problem.

In Europe, silver compounds from textiles and cosmetics have the highest environmental exposure when the washing or rinsing water is treated in sewage treatment plants. Subsequent silver releases from these sewage treatment plants into soil or surface waters are classified as low. However, silver releases in concentrations that are toxic to some aquatic organisms are possible but unlikely.

What are the consequences for microbial resistance?

Some research suggests that in some cases (in vitro studies, but not confirmed in situ studies) bacteria could become generally resistant to the antibacterial effects of silver. However, it is currently impossible to assess whether the use of silver nanoparticles increases antimicrobial resistance or not. This significant knowledge gap needs further research.

With the widespread and increasing use of products containing nanosilver, both consumers and the environment are exposed to new sources of silver. Although there have not yet been any clear adverse effects associated with exposure to silver, side effects caused by the use of nanosilver particles cannot be ruled out and should be further assessed.

This fact sheet is based on the opinion of the Independent Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR):
"Nanosilver: safety, health and environmental effects and role in antimicrobial resistance" ’