Nano in the Construction Industry (NanoTrust Dossier No. 032en – August 2012)

In the construction industry and in architecture, nanotechnology and nanomaterials provide new opportunities. “Nano-products” for construction purposes are currently found in four main sectors: cement-bound construction materials, noise reduction and thermal insulation or temperature regulation, surface coatings to improve the functionalities of various materials, and fire protection. At the present time, nanomaterials – and therefore “nano-products” – remain considerably more expensive than conventional alternatives due to the required production technology, and the technical performance of many products remains to be demonstrated. Both industry workers as well as end users can come into contact with nanomaterials when using a “nano-construction material” and need to be protected from potential health hazards. Information on which nanomaterial is found in which form and concentration in a product is often unavailable, particularly to end users. Once a nanomaterial is solidly embedded in a matrix, for example in concrete or in insulation material, then the probability of exposure is very low or non-existent according to current knowledge, as long as the product is not destructively worked or processed. When workers spray a nano-surface layer or mix mortar at a construction site, for example, they are subject to a potential health hazard by inhaling the dust or tiny droplets of liquid (aerosols). As “nano-construction products” currently play a subordinate role on the market, the current environmental threat due to nanomaterials appears to be low. Nonetheless, virtually no data are available on exposure, so that no comprehensive risk assessment can currently be undertaken for any nanomaterial