Nanos and textiles

Nanos and textiles

By the AVICENN team – Last updated July 2022

Why are there nanos in textiles?

On the internet, talks praising the merits of nano-additive textiles is flourishing. Nanomaterials can be found in fabric dyes or in textiles that are stain and/or water repellent¹The NanoSphere® coating from the Swiss company Schoeller, antibacterial and/or anti-odor²See for example:
– First controls of the DGCCRF on nanosilver textiles in France, VeilleNanos, June 3, 2022
– Pharma Calcio enters the arena with the new antibacterial fabric Ti-energy to better protect its athletes, Erreà, June 25, 2020 : “Parma Calcio 1913” will wear the jersey with the cross realized in a new special high-tech fabric developed by Erreà Sport to barrier microbes and bacteria. (…) the presence of zinc oxide nanoparticles (permanently encapsulated in the fibers), exerting an antibacterial function (…)”.
– Non-polluting, super-resistant, smart: what will the clothes of the future really look like?“, Sciences & Avenir, January 2020 : “some fibers are worked with nanomaterials to become antibacterial, and thus be washed less often. If gold and silver nanoparticles or graphene oxide, integrated into conventional fibers, have proven their effectiveness in this area, their health and environmental impact as well as their high cost do not make them viable solutions. Polymer-based nanomaterials, which are cheaper and greener, also have antibacterial properties, but for a limited time, due to their unfortunate tendency to trap bacteria in the fiber over time. Thus, researchers from the College of Textiles and the Institute of Textiles at Donghua University have been looking for – and perhaps finally found – the “right recipe” for an antibacterial textile: the durable guanidine-based nanogels. Grafted into cotton or other natural fibers, these have the ability to disrupt the bacterial cell membrane while remaining effective after about 50 washes.”, depolluting³See for example:
– IS FRESH – The self-cleaning fabric for permanent purification, Société Trajet-Aunde (France): “It is a new representative of nanotechnology for hygiene and health” (accessed in May 2020)
–Non-polluting, super-resistant, intelligent: what will the clothes of the future really look like, Sciences & Avenir, January 2020
– AVICENN survey on IKEA’s “air purifying” curtains, VeilleNanos, 2021, anti-UV⁴In 2017, the Italian brand Castelli also replaced the usual black jerseys and shorts of the British Sky team with a white version with titanium dioxide integrated in order to reinforce the solar protection (in the form of nano-filament woven into the polyester of shorts and leggings and also in the form of dye to act as a second layer of protection against the sun) before extending the use of titanium dioxide to amateur outfits, such as the Inferno shorts and Climber’s 2.0 jerseys. Source: How titanium dioxide protects cyclists from the sun, TDMA, March 2018, warming⁵See for example:
–A high-tech textile to stay comfortable outdoorsAmerican Chemical Society, May 5, 2021: researchers “made a layered fabric made of porous fibrous polymers. To trap warmth in the cold, they coated the heating side in zinc and copper nanoparticles to absorb solar energy and keep in thermal radiation from the body”.
– Flexible material shows potential for use in fabrics to heat, cool, Laura Oleniacz, Phys.org, July 2, 2020 or on the contrary refreshing⁶See for example:
– This textile reflects light to cool your skin, Korii, July 19, 2021 and New ‘mirror’ fabric can cool wearers by nearly 5°C, ScienceMag, July 8, 2021 (mainstream article) and Hierarchical-morphology metafabric for scalable passive daytime radiative cooling, Zeng S et al, Science, 2021 (scientific article)
– Flexible material shows potential for use in fabrics to heat, cool, Laura Oleniacz, Phys.org, July 2, 2020
– Nanomaterial-based textile coating for cooling textiles, Mode in Textiles, April 28, 2020
– 3D printed clothes that can cool you down, Digital Century, Nov. 15, 2017, anti-mosquito⁷See in particular Investigation and Mathematical Analysis of Avant-garde Disease Control via Mosquito Nano-Tech-Repellents, COST, July 11, 2017 or fireproof⁸Dupont has developed nanomaterials for textiles for firefighters, the military and law enforcement (see Alpex expands in technical textiles with Italian NT Majocchi, Les Echos, 21 April 2022). See also: Nanotechnology in Fire Protection-Application and Requirements, Rabajczyk A et al, Materials, 14(24): 7849, 2021 Flexible carbon nanotube fibers woven into clothing gather accurate EKG, heart rate, Phys.otg, August 2021), scented or even connected (T-shirts with carbon nanotubes are being developed, for example, to enable athletes to monitor their heart rate in real time ⁹Cf. Flexible carbon nanotube fibers woven into clothing gather accurate EKG, heart rate, Phys.otg, août 2021), etc.

Which textiles contain nanos?

In the field of textiles, as in others, it is difficult to distinguish between “promises” still in the research and development stage and nano applications that are actually commercialized.

Unlike cosmetics or packaged food products that are subject to [nano] labeling requirements, the regulations do not require manufacturers or brands to indicate the substances applied to textiles or to mention their nanoscale.

In the French r-nano register, only about twenty declarations of nanoparticles concern textiles, but without the possibility to identify the products concerned.

By 2018, however, Avicenn spotted U.S.-based Nanotex, which supplies more than 100 brands in clothing, interior decoration and household linen, including Calvin Klein, GAP, Hermes, Intersport, Nike, O’Neill and others.

In 2022, more than 600 textile products were listed in the NanoDatabase, a database created ten years ago in Denmark to identify products containing nanomaterials: sportswear, gloves, hats, jackets, socks, shoes, boxers and bikinis, anti-covid masks. “Among the brands, as many small players little known to the general public as heavyweights such as Patagonia, Reebok, Hanes, Burton or Adidas”¹⁰Cf. “When the dressing room intoxicates us”, Dorothée Moisan, Kali, n°2, December 2021.

After the first concerns regarding nanosilver in textiles…

Many articles of sportswear appear to be treated with nano silver. In 2018, Svenskt Vattens, the Swedish water and wastewater union alerted on antibacterial and anti-odor silver from sports textiles¹¹Cf. Adidas continues to sell clothing treated with toxic silver despite the risk to aquatic environments, Svenskt Vattens, December 17, 2018. It is the largest known source of silver in water treatment plants, a threat to our lakes and seas, and a risk for the spread of antimicrobial resistance. Brands and retailers are asked to stop selling clothing treated with silver to protect water (Adidas was singled out as the worst performer).

A recurring question on women’s forums and social networks: do menstrual panties contain silver nanoparticles¹²Again, it is difficult to know-See for example “Nanoparticles in our panties?” in La culotte menstruelle : une vraie révolution?, ChEEk Magazine, November 2017? In 2019, the NGO Women’s Voices for the Earth expressed concerns about the use of nanosilver in menstrual pads and underwear¹³Cf. Concerns About Nanosilver in Period Products, WVE, April 2019, due to health AND environmental risks .
As is the case for food or cosmetic products, some brands use the “nano-free” mention as a selling point, like for some menstrual panties¹⁴See for example:
– A periodic panty: 12 hours of serenity, Réjeanne: “it is made in France, without silver nanoparticles and its fabrics are certified Oekotex 100” (page consulted in June 2020)
–Discover FEMPO, the French menstrual panties brand!”, Madmoizelle, May 2018: “EMPO emphasizes that the panties do not contain silver or copper nanoparticles, unlike other brands.”.

In March 2020 in the United States, several associations protested against the authorization by the U.S. Environmental Protection Agency (EPA) of a nanosilver-based product intended to be applied to textiles, in view of the health and environmental risks that it could entail.

… other concerns about the use of nanoparticles of titanium dioxide or zinc oxide in textiles

In June 2020, the Italian brand Erreà Sport announced that its jersey worn by the club Parma Calcio 1913 would contain zinc oxide nanoparticles (“permanently encapsulated in the fibers”), with antibacterial properties¹⁵Cf. Pharma Calcio enters the arena with the new antibacterial fabric Ti-energy to better protect its athletes, Erreà, June 25, 2020 : “Parma Calcio 1913” will wear the jersey with the cross realized in a new special high-tech fabric developed by Erreà Sport to barrier microbes and bacteria. (…) the presence of zinc oxide nanoparticles (permanently encapsulated in the fibers), exerting an antibacterial function (…)”.. In July Avicenn asked Oeko-Tex if they had certified these T-shirts and what policy they had in place regarding nanoparticles / nanomaterials. OekoTex replied that these nanoparticles were not allowed.

What is the benefit/risk ratio?

As early as 2014, the Global Organic Textile Standard (GOTS) certification banned from its standards the use of any deliberately added nanoparticles. It looks like an exception to the rule…

It is still too rare to see real benefit/risk assessments¹⁶Some exceptions:
–Health and safety concerns of textiles with nanomaterials, Almeida L & Ramos D, IOP Conf. Ser.: Mater. Sci. Eng. 254: 102002, 2017
–ECOTEXNANO: “Safe use of nanomaterials in the textile finishing industry” (2013-2016), European project. Antimicrobial applications in the medical field¹⁷See for example:
– Metal and metal oxides nanoparticles in healthcare and medical textiles, in Medical Textiles from Natural Resources, The Textile Institute Book Series, 341-371, 2022
– Medical textiles, Morris H & Murray R, Textile Progress, 52(1-2), 2020
– Hospital: embedding small copper particles in doctors’ scrubs to reduce the spread of infection, Why Doctor?”, February 17, 2018
– Textile medical devices impregnated with active ingredients, Note de veille, CETIM, April 2012 for example, can be justified (provided that they have proven their effectiveness in real conditions and are subject to adequate waste management in particular) but what about consumer textiles?

In 2020, Avicenn had IKEA’s “air purifying” curtains tested. These were found to be covered in titanium dioxide nanoparticles… and have since been withdrawn from the market (IKEA realized also that they were not as depolluting as expected).

Most “intelligent” textiles seem to bet on nanomaterials¹⁸See for example:
–Printed flexible electronics – one step closer to smart clothing, University of Oulu, 2020
–Non-polluting, super-resistant, intelligent: what will the clothes of the future really look like, Sciences & Avenir, January 2020
–Smart and comfortable new nanocomposite textiles for high-tech clothing, Nanowerk (University of Bayreuth), February 2018
–Innovative textiles: the intelligence is in the design, Up Magazine, June 2013 but for what actual positive (or negative) effects? This should be something worth considering.

June 2022: first controls of the DGCCRF on nano silver in textiles in France

On June 3, 2022, the Directorate General for Competition, Consumer Affairs and Fraud Control (DGCCRF) announced that it would conduct an investigation in 2021 on so-called “technical” textiles,¹⁹Technical textiles: between innovation and overbidding, DGCCRF, June 3, 2022 highlighting an overkill in the use of commercial claims (resistance, anti-fire, anti-stain, anti-UV, etc.) and a tendency to exaggerate the real benefits provided by the products. In particular, two of the six antibacterial or “anti-odor” products analyzed were treated with silver nanoparticles, which are being classified because of their risks… and without this information being made available to consumers, which is contrary to the Biocides Regulation.

Following the DGCCRF’s investigation, the two operators marketing these two products withdrew them from the market.

To our knowledge, these are the first controls by the French public authorities on the presence of nanoparticles in textiles.

To be continued…