Nanoparticles can be bad for you, but so too is lots of other stuff, and it can be incredibly difficult if not impossible to determine exactly what does what to cells in the body. This is the honest answer to research questions posed by Finnish and American physicists looking at how carbon-based nanoparticles may adversely affect health.
I shall not comment on the detail of the research carried out by Emppu Salonen, Ilpo Vattulainen, Pu-Chun Ke and others. I have not yet read their journal paper beyond the abstract, and in any case it is not the point of this article. What strikes me is a particular comment made by the scientists in the press release covering their work.
The first paragraph of the press release is designed to grab the attention of busy science journalists, referring as it does to the need for more research into the health and safety consequences of engineered nanomaterials, and the fact that the European Union chemicals directive REACH does not even mention nanomaterials. Then there is the concern that engineered nanoparticles may become the asbestos of the 21st century. So far, so good; a hundred words in and your average bleary-eyed hack is probably still reading this story in his email digest of the day’s science press releases from around the globe.
Only around 80 words of the press release are devoted to the work done by the Finnish-American team. What we learn is that the cages of carbon atoms known as fullerenes (e.g., “buckyballs”) can cause cell death, but only when present in a cell culture at the same time as gallic acid. Now that is a very interesting result, and it could do with reporting in more depth. Just don’t expect that from me, as I have neither the time nor the inclination to do that here. And don’t expect it either in a brief press release. It cannot be done adequately in so few words, believe me!
It is the penultimate paragraph of the Tampere University announcement that stands out for me:
“The research demonstrates how difficult it is to map out the health effects of nanoparticles. Even if a certain nanoparticle does not appear toxic, the interaction between this nanoparticle and other compounds in the human body may cause serious problems to cell functions. The number of possible combinations of nanoparticles and various biomolecules is immense. Thus, it is practically impossible to research them systematically.”
What this is saying in effect is that the ‘nano’ aspect to the materials is only one small part of it, and it is little different from any other toxicology question in which problems arise from complex combinations of chemicals in the environment. It is, as the researchers say, “practically impossible” to study all possible combinations in a systematic manner.
No-one in their right mind would, based on the limited data we have to hand, make firm predictions regarding the health and safety consequences of engineered nanomaterials that have yet to find widespread use outside the laboratory. We will no doubt discover in time that certain materials and combinations of materials lead to problems. But, as with any other novel materials, this will take time, and it makes no sense to damn nanomaterials as especially hazardous.