Silver nanoparticles

The (nano)silver particles

By AVICENN Team – Last Added November 2021

What quantities on the market?

Hundreds of tons of silver nanoparticles are produced worldwide every year¹Some estimates of nanosilver production:
– In 2013, a projection bet on a world production of nanosilver between 450 and 542 tons for 2014 (The global nanotechnology and nanomaterials industry – Technology Report No. 68, Future Markets, Inc., 2013)
– In 2011, the production of nanosilver was estimated at 20 tons for the United States alone (Estimating production data for five engineered nanomaterials as a basis for exposure assessment, Hendren CH et al., About Sci Technol, 45:2562-2569, 2011)
– In 2008, the world production of nanosilver had been estimated at 500 tons per year (cf. Mueller NC and Nowack B, Exposure modeling of engineered nanoparticles in the environment, Environmental Science & Technology, 42(12): 4447-4453, Jun 2008.

From 2013 to 2017, less than 10 kg of nanosilver was declared each year as having been produced and/or imported in France as part of the mandatory declaration ; in 2018, for the first time, the reported volume of nanosilver moved into the upper range, including between 10 and 100 kg²SeeThe R-Nano register – The annual declaration of “substances with nanoparticle status” in France, mandatory since 2013,veillenanos.fr.

However, there is much more nanosilver on French soil: this declared "nano-quantity" illustrates the difficulties in understanding the real quantities of nanomaterials present on French soil via the r-nano register and the annual declaration, victim of the “strainer effect”.

What properties?

Silver nanoparticles are used primarily as antibacterial or antifungal in the medical and pharmaceutical sector, in packagings (cardboard, plastic) and plastic films, In cosmetics (deodorants, soaps), in small care equipment (hairbrushes, electric razors, toothbrushes, hair dryers, curling irons, etc.), in the textiles (medical staff gowns, fabrics used in the operating room), on computer and telephone keyboards...

What products?

Many inventories of products containing nanosilver are available online: they list between 200 and 500 products, but are probably far from being exhaustive, given that the labeling obligation is not respected.

The few kilos of nanosilver (less than 10) declared to the R-nano register in 2017 were classified in the following categories³SeeThe R-Nano register – The annual declaration of “substances with nanoparticle status” in France, mandatory since 2013,veillenanos.fr :

• vehicles
• machines, mechanical devices, electrical/electronic items
• laboratory chemicals
• metals and alloys
• biocidal products (e.g. disinfectants, insecticides)
• use as a laboratory reagent
• production of metal powders (wet process)
• formulation [mixing] of preparations and/or reconditioning (except alloys)
• general manufacturing, e.g. ex. machinery, equipment, vehicles,
• other transport equipment
• scientific research and development
• manufacture of fine chemicals

Silver nanoparticles are present in the food additive E174, silver dye used in foodstuffs (mainly decorations for pastries).

Non-approval as a biocide of silver "as a nanomaterial"

In August 2021, the decision not to approve silver as a biocide "as a nanomaterial" has been published in the Official Journal of the European Union (OJEU) for product types 2, 4 and 9.

From a legal point of view, this decision is made due to the absence of a request from an industrialist to obtain an authorization to use nanosilver for biocidal purposes.⁸Indeed, it happens that manufacturers do not submit an authorization application file (or withdraw it or do not renew it) for a biocide which does not meet the stricter requirements of the new biocides regulations (or for which they consider that the cost will be too high to meet it). – and not because of (proven) health and/or environmental risks of nanosilver.

What risks?

Le nanosilver is being classified at European level.

Depending on the uses, the “risk-benefit” balance will be different. If it can be positive for strictly limited medical applications (serious burns for example), it is negative in domestic refrigerators⁹See for example The cost-benefit analysis of the use of nanoparticles in refrigerators, ICSI, Cahiers de la sécurité industrielle, February 2011.