Ultra durable and self-sensing cement are some of the inventions made possible by nanotechnology. So what’s stopping some businesses from investing in it?


The use of nanomaterials joins a list of innovations touted to be the next big thing for the construction industry.

Nanotechnology is not new – stained glass windows and ceramics all used nanomaterials during the 14th and 15th centuries – but what is relatively new is the ability to manipulate nanoparticles to create ‘smart’ products and durable materials.

Microscopic nanofibers, for instance, is the latest innovation that has got construction businesses excited. Added to concrete mix, carbon nanofibers create crack-free concrete, reinforcing the strength of buildings.

Even more impressive, is its self-sensing potential. Piezoelectric materials such as nanofibers have the capability to accumulate electrical charge by responding to applied mechanical stress. Such materials could thereby be used as ‘sensors’, converting motion into electric signals that record or detect motion or ‘actuators’, which convert electric energy into mechanical work.

Adding to the list of innovative pros, nano-scale materials have been used to create self-cleaning glass, removing the need for detergent. This has been made a reality with the use of microcrystalline titanium oxide – a nanoparticle also used in food, toothpaste and sun creams – which coats the glass. The particles react to daylight, breaking down any dirt on the glass and, when rainwater hits it, the filth slides off.

On building sites, accidents have been reduced because workers no longer need to access hard-to-reach glass to clean it.

Like any new development, however, nanotechnology comes with risks.

City University London photonics lecturer Arti Agrawal says: “The thing about nanotechnology is that we are manipulating it, but we don’t understand it fully. People are worried about hazards to human beings. So if you have small nanoparticles in fabrics or in medicines or in food, for example, will that go into the human body and cause diseases? We don’t know that. Or will it lead to a lot of pollution and hazardous waste? Those are some of the worries.”

As Agrawal pointed out, the biggest concern is that there has been no conclusive research into the risk of nanotechnology to human health, the environment and financial stability.

The National Institute for Occupational Safety and Health (NIOSH) in the US, however, has chosen to vie on the cautionary side, recommending that airborne exposure to nanomaterials, such as nano titanium dioxide, is limited to 0.3 mg/m3. This is significantly lower than what is advised for non-nano titanium, at 2.4mg/m3.

It also raised concern around the use of carbon nanotubes “which can have asbestos-like effects due to their needle-like shape and bio persistence”, putting the airborne limit of this particular material to of 0.001g/m3.

Scientists agree that when nanoparticles are bound – contained on a computer chip or a mobile phone, for example – the risk is much lower than when the particles are airborne.

Although the cons list paints an inconclusive picture of the threats, risk aversion is a barrier to innovation. And that in itself is a risk.