Nanos and textiles

Nanos and textiles

By AVICENN Team – Last Added July 2022

Nanos for what properties?

On the net, the discourse extolling the merits of nano-additive textiles is flourishing. Nanomaterials can be found in fabric dyes or in stain-resistant and/or water-repellent textiles¹The NanoSphere® coating from the Swiss company Schoeller, antibacterial and/or anti-odor²See for example:
- First DGCCRF checks on nanosilver textiles in France, EveNanos, June 3, 2022
- Pharma Calcio descends into the arena with the new Ti-energy antibacterial fabric to better protect its athletes, Erreà, June 25, 2020: “The Parma Calcio 1913 club will wear the cross jersey made in a new special high-tech fabric developed by Erreà Sport to act as a barrier to microbes and bacteria. (…) the presence of zinc oxide nanoparticles (permanently encapsulated in the fibres), exerting an antibacterial function (…)”.
- Non-polluting, super-resistant, smart: what will the clothes of the future really look like?, Science & Future, January 2020: “Some fibers are worked with nanomaterials to become antibacterial, and therefore be washed less often. While gold and silver nanoparticles or even graphene oxide, integrated into conventional fibers, have proven their effectiveness in this area, their health and environmental impact and 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 sought – and perhaps ended up finding – the “right recipe” for an antibacterial textile: durable guanidine nanogels. Grafted into cotton or other natural fibers, these have the ability to disrupt the bacterial cell membrane while remaining effective after about fifty washes. », depolluting³See for example:
- IS FRESH – The self-cleaning fabric for permanent purification, Company Trajet-Aunde (France): “It is a new representative of nanotechnology for hygiene and health” (accessed May 2020)
-Non-polluting, super-resistant, smart: what will the clothes of the future really look like?, Science & Future, January 2020
- AVICENN's investigation into IKEA's 'air-purifying' curtains, EveNanos, 2021, Sun Creme⁴In 2017, Italian brand Castelli also replaced Great Britain's Sky team's usual black jerseys and bib shorts with a white version featuring titanium dioxide integrated in order to reinforce sun protection (in the form of nano-thread woven into the polyester shorts and bib shorts and also in the form of dyeing to act as a second layer of protection against the sun) before extending the use of titanium dioxide to amateur clothing, such as Inferno bib 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 outdoors, American 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 condition your skin, Korii, July 19, 2021 and New 'mirror' fabric can cool wearers by nearly 5°C, ScienceMag, July 8, 2021 (general public 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
- Textile coating based on nanomaterials for cooling textiles, Fashion in Textiles, April 28, 2020
- 3D printed clothes that can cool you down, Digital Century, November 15, 2017, mosquito repellent⁷See in particular Investigation and Mathematical Analysis of Avant-garde Disease Control via Mosquito Nano-Tech-Repellents, COST, July 11, 2017 or fireproof⁸Dupont has thus developed nanomaterials for textiles intended for firefighters, the military and law enforcement (cf. Alpex expands into technical textiles with the Italian NT Majocchi, Les Echos, April 21, 2022). See also, in French: Nanotechnology in Fire Protection—Application and Requirements, Rabajczyk A et al., Materials,  14(24): 7849, 2021, perfume diffusers, even connected (T-shirts with carbon nanotubes are developed for example to allow athletes to monitor their heart rate in real time⁹See Flexible carbon nanotube fibers woven into clothing gather accurate EKG, heart rate, Phys.otg, August 2021), Etc.

How do you know which textiles contain nanos?

In the field of textiles as in others, it is difficult to distinguish the "promises" still in the state of research & development from the nano applications actually marketed.

Unlike cosmetics or packaged food products subject to a labeling obligation [nano], regulations does not oblige manufacturers or brands to indicate the substances applied to the textiles nor to report their nanometric scale.

In the French register r-nano, only about twenty declarations of nanoparticle substances relate to textiles, without it being possible to identify the products concerned.

In 2018, Avicenn had nevertheless spotted the American company Nanotex, which supplies more than 100 brands in the field of clothing, interior decoration and household linen, including Calvin Klein, GAP, Hermès, Intersport, Nike, O'Neill, etc.

In 2022, more than 600 textile products are listed in the NanoDatabase, a database created ten years ago in Denmark to identify products containing nanomaterials: sportswear, gloves, hats, jackets, socks, shoes, underpants and bikinis, anti-covid masks. “Among the brands, as many small players little known to the general public as heavyweights like Patagonia, Reebok, Hanes, Burton or Adidas”¹⁰See “When the dressing room intoxicates us”, Dorothée Moisan, Kali, No. 2December 2021.

After the first questions about nano-silver in textiles…

A lot of sportswear would processed at nanosilver. In 2018, Svenskt Vattens, the Swedish Water and Wastewater Union warned about antibacterial and anti-odor silver coming from sports textiles¹¹See 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, as well as a risk of spreading antimicrobial resistance. Brands and distributors are asked to stop selling silver-treated clothing 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 nanoparticles?¹²Here again, difficult to know See for example “Des nanoparticules dans nos culottes? » in Menstrual panties: a real revolution?, ChEEk Magazine, November 2017? In 2019, the NGO Women's Voices for the Earth is concerned about the use of nanosilver in menstrual pads and underwear¹³See Concerns About Nanosilver in Period Products, WVE, April 2019 , due to risks for health AND for the environment.
It is possible that, like food or cosmetic products, some brands, on the contrary, play the "nano-free" card, such as some menstrual panties¹⁴See for example:
- Period panties: 12 hours of serenity, Rejeanne:  » it is made in France, without silver nano-particles and its fabrics are certified Oekotex 100″ (page consulted in June 2020)
-Discover FEMPO, the French menstrual panty 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 have mobilized against the authorization by the US Environmental Protection Agency (EPA) of a product based on nano-silver intended to be applied on textiles, in view of the health and environmental risks that it would be likely to train.

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

In June 2020, Italian brand Erreà Sport announced that their shirt worn by the club Parma Calcio 1913 should contain zinc oxide nanoparticles ("permanently encapsulated in the fibers"), exerting an antibacterial function¹⁵See Pharma Calcio descends into the arena with the new Ti-energy antibacterial fabric to better protect its athletes, Erreà, June 25, 2020: “The Parma Calcio 1913 club will wear the cross jersey made in a new special high-tech fabric developed by Erreà Sport to act as a barrier to microbes and bacteria. (…) the presence of zinc oxide nanoparticles (permanently encapsulated in the fibres), exerting an antibacterial function (…)”.. In July Avicenn asked to Oeko-Tex if it had certified these T-shirts and what policy this organization had put in place concerning nanoparticles / nanomaterials. OekoTex replied that these nanoparticles were not authorized.

What is the benefit/risk ratio?

Since 2014, GOTS (Global Organic Textile Standard) certification has banned from its standard the use of any nanoparticle deliberately added. But this is a priori an exception to the rule…

It is still too rare to see real benefit/risk approaches¹⁶A few exceptions:
-Health and safety concerns of textiles with nanomaterials, Almeida L & Ramos D, IOP Conf. Ser.: Mater. Science. Eng., 254:102002, 2017
-ECOTEXNANO : “Safe use of nanomaterials in the textile finishing industry” (2013-2016), European project. Antimicrobial applications in the medical environment¹⁷See for example:
- Metal and metal oxides nanoparticles in healthcare and medical textilesin 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: incorporating small copper particles into doctors' gowns to reduce the spread of infections, Why doctor?, February 17, 2018
- Textile medical devices impregnated with active ingredients, Watch note, CETIM, April 2012 for example can be justified (subject to having demonstrated their effectiveness in real conditions and to being subject to adequate management of waste management in particular); but what about consumer textiles?

In 2020, Avicenn had IKEA's 'air-purifying' curtains tested who turned out covered in titanium dioxide nanoparticles… and which have since been withdrawn from the market (IKEA realized that they were not as depolluting as expected!).

A counter-example to ponder… both the field of “intelligent” textiles seems to bet on nanomaterials¹⁸See for example:
-Printed flexible electronics – one step closer to smart clothing, University of Oulu, 2020
-Non-polluting, super-resistant, smart: what will the clothes of the future really look like?, Science & Future, 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– for what real effects (beneficial… or negative)?

June 2022: First DGCCRF checks on nanosilver textiles in France

On June 3, 2022, the Directorate General for Competition, Consumer Affairs and Fraud Prevention (DGCCRF) announced that it had conducted a survey in 2021 on so-called “technical” textiles¹⁹See Technical textiles: between innovation and one-upmanship, DGCCRF, June 3, 2022 highlighting an escalation in the use of commercial claims (resistance, fire-retardant, stain-resistant, anti-UV, etc.) and a tendency to exaggerate the real benefits provided by the products. In particular, two of the six antibacterial or “anti-odour” products analyzed were treated with silver nanoparticles, currently being classified due to their risks… and without this information being brought to the attention of consumers, contrary to what is required by the Biocides regulation.

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

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

To be continued ...