Nanos in the construction industry

Nanos in the construction industry

By the AVICENN team – Last updated September 2022

The construction industry is one of the top users of nanomaterials¹ See the number 1 sector according to the report Industrial realities in the field of nanomaterials in France – Analysis of the reality of the weight of nanomaterials in the industrial sector concerned, D&Consultants for the General Directorate for Competitiveness, Industry and Services (DGCIS, of the Ministry of Productive Redress), June 2012 . A list of nanomaterials used in the construction industry is available in the annual reports on the mandatory declaration of nanomaterials, prepared by the French National Health and Safety Agency (ANSES) and published by the Ministry of Ecology²Cf: https://www.ecologie.gouv.fr/nanomateriaux#e3.

In which construction products are nanomaterials found?

Self-cleaning windows, stained wood, cement and concrete³See in particular:
– Fracture toughness of one- and two-dimensional nanoreinforced cement via scratch testing, Akono AT, Philosophical Transactions of the Royal Society A., 379, 2203, August 2021
– Strengthening cements by incorporating nanomaterials, Techniques de l’ingénieur, September 10, 2021
– Nanos in concrete, Mathieu Porchet, Founding Partner at prllx, June 16, 2020, paint⁴See in particular:
– Pigments: The oldest nanomaterials in human history facing modern day challenges, Eurocolour & VDMI, Nanopinion, EUON, June 2020
– How about a little thought to lower the air conditioning bill, batiactu, February 2019: “a white ceramic nanoparticle paint for flat roofs can lower the air conditioning bill for large buildings”
– List of nano-pigments on the EU market: More than 80 nano-sized pigments have been identified on the European market in 2018 by the European Chemicals Agency (ECHA) (particularly so-called “depolluting” cements and paint, whose benefit-risk ratio is not currently positive⁵See in particular: Paint to purify ambient air, CEA Liten, November 2020), varnishes, insulation materials, tiles and joints, switches, air ducts, sidewalks and roads⁶These are nanocoatings of concrete slabs designed by the University of Twente, in the Netherlands, which are supposed to break down nitrogen oxides (harmful urban pollutants) marketed in France by the company URBAPT. Cf. “Titanium: promises and risks of a depollutant” in La civilisation des nanoproduits, Jean-Jacques Perrier, éditions Belin, September 2017, nanomaterials are increasingly used in the building and construction industry.

However, there is no legislation requiring the labeling of products used in construction and public works, as is the case in cosmetics, biocides and food.

The R-nano register does not identify precisely the products concerned.

Nanomaterials do not (or very rarely) appear in the Environmental and Sanitary Declaration Sheets (ESDS for construction and decoration products) nor in the safety data sheets (SDS for substances and mixtures) despite the obligation, in force since 2021, to include information on nanoforms in SDS.

It is therefore necessary to cross-reference sources ⁷A few documents can help you, including:
Nano Pigments Inventory, ECHA, 2018: more than 80 nano-sized pigments identified on the European market
-The nanoshop.com website allows to find nanomaterials used in construction (glass, metal, …).
– Elcosh NANO – Construction Nanomaterial Inventory, Center for Construction Research and Training (CPWR): 400 products as of September 2014
–Aide au repérage des nanomatériaux en entreprise, INRS, June 2014
–Sheet to help identify nanomaterials (construction and public works), Direccte Bretagne, October 2013 , and interview manufacturers and suppliers, but with no guarantee of being be able to identify nanomaterials in finished products – except through laboratory testing.

What are they used for?

Nanomaterials are used in the construction industry for their new or enhanced properties compared to conventional materials, structured at the milli- or micrometer scale:

• the Amorphous silica fumes, 100 times smaller than cement grains, have a very high surface area, from 15 to 30 m²/gram. As with the carbon nanotubes, they confer properties of fluidity or increased mechanical resistance, for “very high performance” concretes or nano-structuring repair mortars
  
• the nanoparticles of titanium dioxide and zinc oxide nanoparticles are praised for their ability to reduce fouling, under the effect of UV, of materials used in particular in the building works⁸Cf.:
  – “La Cité des arts et de la musique” in Chambéry, inaugurated in 2003, was one of the first buildings whose roofing cement included TiO2; it was soon followed by the police headquarters in Bordeaux and the Mermoz block in Maisons-Laffitte. Other examples of self-cleaning white buildings using titanium dioxide cements are the Italian Pavilion at the 2015 World Expo in Milan and the Jubilee Church in Rome, inaugurated in 2007″: “Le titane : promesses et risques d’un dépolluant” in La civilisation des nanoproduits, Jean-Jacques Perrier, Belin editions, September 2017.
  – Nano-coating to protect buildings against pollution, Youris, September 2017
  – Eco-efficient construction and building materials, Torgal, FP & Jalali, S, Constr. Build. Mater., 25, 582-590, 2011
  – Application of titanium dioxide photocatalysis to create self cleaning materials, Stamate, M.; Lazar, G. Model. Otpim. Mach.Build. Field (MOCM), 13 (3), 280-285, 2007 as cement, ceramics, paints, varnishes
  
• silver nanoparticles are used for their antibacterial or antifungal properties
  
• aluminum oxide increases the scratch resistance of materials
  
• nanofoams (hydro-NM-oxide) and nanostructures provide good thermal and sound insulation.
  

What are the associated risks?

Health and environmental risks

The large-scale use of materials containing nanomaterials is not without risks for the environment and the health of exposed workers.

• In 2012, INERIS intervened publicly on the issue of Nanoparticles and construction materials. The same year, INRS published a specific note on the Use of nanometric titanium dioxide – Special case of the construction industry.
• At the end of 2017, the OPPBTP presented its work and approach on nanos to the ANSES nano dialogue committee.
• Mid-2018, the High Council for Public Health (HCSP) published a report⁹Cf. Protecting workers and people in the vicinity of sites producing or handling titanium dioxide nanoparticles, High Council for Public Health, June 25, 2018 calling for the protection of workers and populations in the vicinity of industrial sites producing or handling nano-TiO2, with a set of practical recommendations for public authorities and industrialists. It recommended the following: “In the specific case of construction and recycling, additional research on the emissivity of street furniture should be conducted because it contains _TiO2 nanoparticles (nano-paving, nano-concrete, self-cleaning glass); their results should be communicated to occupational health services”.

• In 2019, the European Scientific Committee on Health, Environmental and Emerging Risks (SCHEER) ¹⁰Cf. Statement on emerging health and environmental issues, Scheer, 2018 issued an alert on nanoparticles released into the environment by construction materials and waste (during renovation and demolition processes, during recycling, landfill or incineration but also when nanocoatings are not properly fixed, when they degrade). It pointed out that nanoparticles that end up in aquatic systems can have adverse effects on aquatic and marine life and in soils. Essential microbial interactions may be disrupted. It deplored the lack of regulations requiring the labeling or identification of building materials containing nanomaterials, which hinders the necessary identification of the sources and flows of nanomaterials that may be released – as well as the assessment of the risks they may pose.
• In 2019, an LNE webinar presented the risks associated with thermal degradation of nanomaterials in transportation and housing.

Without the possibility of identifying whether nanomaterials are present in the materials used in buildings, how can we be sure of their recyclability? This lack of information on the nature of materials poses a big problem for the circular economy in the building industry.

Economic risks

The risks are not only sanitary and environmental, they are also economic, particularly for the owners. As is the case for asbestos removal, still an issue today and very expensive¹¹in particular 25 years of asbestos: the scandal continues, InfoDiag, Special Edition, September 2022, the authorities could, in the future, order the “denanoparticulation” of buildings, during paint renovation or demolition of a building for example, and the owners would have to bear the costs.

Precautionary measures in the face of risks

Since 2008, the Grand Council of the Republic and Canton of Geneva has advised against the use of TiO₂ nanoparticles on state construction sites and in private companies’ buildings¹²Health: straight into the wall… self-cleaning, Alternative Santé, January 6, 2016 and Report M 1741-A of the State Council to the Grand Council of Geneva, 2008. This decision was based on a study carried out by the Cantonal Service of Industrial Toxicology and Protection against Indoor Pollution which considers that it is “irresponsible to use such a product before even researching the known hazards and assessing their risks”, and deplores “the premature use of these products in Italy, France and Belgium” and wishes “that such carelessness is not repeated in our Canton”¹³Annex 2 of the previous document..

What research is done on this subject?

In France, INRS, INERIS, ANSES, CEA and other research organizations in France and abroad are working to find out more. We relay their publications when we find them.