Better knowledge needed about handling of nanomaterials

Her research is about understanding how nanoparticles are generated and released into our environment. What happens to the particles in the air? And, for example, how high are the health risks for those working with production and handling of nanoparticles? Today, the number of application with nanomaterials are rapidly such as graphene, titanium and carbon nanotubes.

Nanoparticles are structures in extremely small sizes, less than 100 nanometres in diameter, which are used to make other materials stronger, increase their conductivity and improve their water-repellent or absorbent properties, among other things.

Investigations in workplaces producing nanomaterials

Christina Isaxon, a researcher at Ergonomics and Aerosol Technology at LTH who works in the strategic research area Nanolund, has measured the proportion of nanoparticles in the air and investigated various work processes in companies that produce nanoparticles. She has also run measurements in workplaces producing materials that contain nanoparticles.

‟We have observed that if you can keep the process and those working with it separate, for example by using fume hoods, as well as personal protective equipment in case a leak should occur in the fume hood, you can minimise the risk of exposure. In general, there is a high level of awareness among staff, particularly in processes where you can logically understand that there is an emission risk. That is really positive.”

It is more difficult to protect oneself when the production of nanoparticles or of material containing nanoparticles requires the use of large machinery, according to Christina Isaxon. A large machine cannot easily be placed under a fume hood, for example. Another factor is that work processes not included in the daily production chain, such as cleaning and maintenance of machines or fume hood filter replacement, are easily forgotten in attempts to chart exposure risks.

‟If you don’t know how dangerous something is, you should always apply the precaution principle, that is, to handle the material as though it were toxic and ensure exposure is minimised at all stages.”

Lack of knowledge

When it comes to nanoparticles, there are still major gaps in knowledge as to their toxicity. Although we know that certain particles are harmful to health, especially if they are biopersistent and fibre-shaped, there is a lack of comprehensive knowledge about how nanoparticles affect us over time and in what concentrations they constitute a health risk. Another parameter is the extent to which manufactured nanoparticles can leak out in nature from other materials, for example when consumers handle the material or if it ends up in a landfill.

Waste management and the safe and sustainable by design concept

This is precisely why Christina Isaxon has extended her research to include questions investigating what happens further on in the lifecycle of a material, when it is crushed, sanded or, at a later stage, sorted in waste management facilities. She is also working with the safe and sustainable by design (SSbD) concept, which is about supporting companies in the production of safer nanoparticles that would still retain their desirable properties. For example, reducing the length of carbon nanotubes makes it easier for the body to break them down if they end up in the lungs. Choosing soluble nanomaterials can also have a positive impact. The air we inhale is humid, which means that soluble particles would be more easily dissolved. In that case, only the chemical effect remains; it can also be harmful but is easier to understand and manage. Soluble particles would not accumulate in nature either, should they end up there.

“Nanomaterials are increasingly used in the construction industry, which may not have the same level of safety awareness as a factory specialized in producing nanoparticles. What happens if a carpenter or a painter is sanding paint containing nanomaterials? Are there nanoparticles in the paint dust? And what happens when concrete with for example carbon nanotubes is crushed at a waste management facility?”

Construction industry to be the next research area

In order to get answers to these questions, Christina Isaxon has started a new interdisciplinary project to investigate nanoparticles in the construction industry. She has also run measurements at waste management facilities to find out which particles are released into the air when processing discarded electronics containing nanoparticles. Early results have shown that nanoparticles can be found in the dust that arises when crushing concrete – but whether they occur in higher concentrations for certain particle sizes in the crushed material is not yet known, nor how the dust containing nanomaterials affects our health. Other studies, on sanding of paint containing nanoparticles, have shown that it seems to be the emulsifying agent in the paint that causes toxic effects rather than whether the sanding dust contains nanoparticles. The manufactured nanoparticles do not seem to be released as completely free particles either; they are mixed with the material in which they were contained.

“We should absolutely not need to fear nanoparticles. That is why it is important to inform yourself about the current status of knowledge. The more we know about the circumstances in which nanoparticles can affect us and our environment, and how, the better we can become at producing safer nanomaterials and handling the materials without risk of exposure.”

Because nano is the future, without a doubt.

“I completely believe that nanotechnology is one of the absolutely best tools we have to solve several of our sustainability challenges, such as cheap and accessible energy or clean water. But, in that case, we must work proactively to produce new knowledge as a basis for safety recommendations and continue to develop concepts such as safe and sustainable by design”, Isaxon concludes.