DIT researchers are studying the impact of man-made nanoparticles on human cells, writes Dr Claire O'Connell
The science of the very tiny is the latest big thing, an approach that is transforming our ability to make smaller and smarter products. But we need to assess the potential safety issues around nanotechnology, according to experts.
A group at Dublin Institute of Technology (DIT) is looking at safety, how man-made nanoparticles affect human cells. Their work suggests we need fresh thinking about how to assess the impact of the nano-revolution.
It is a hot topic in the electronics, energy and biomedical industries and already nanoparticles are used in consumer products such as sunscreens and anti-scratch car paints.
"In terms of public funding, Ireland is up there with the big guns of Japan and the US, and there are plenty of companies here who are using nanotechnology," says Dr Maria Davoren, a post-doctoral researcher at DIT's Radiation and Environmental Science Centre. "So it just seemed right for us to start looking into nanotoxicology."
There is growing concern that man-made nanoparticles need to be appropriately assessed for health and safety as part of basic research, says Dr Davoren. "It's important for everyone that the technology is safe and sustainable. It's no good retrospectively saying 'we didn't see that' and closing the stable door once the horse has bolted."
A major issue is that an agent's physical and chemical properties can change profoundly at the nanoscale because of increased particle number and surface area, explains Dr Davoren. "If the bulk material is safe then we shouldn't just accept the nanoparticle will be safe too," she says.
Her interdisciplinary group is currently working with nanoparticles called single-walled carbon nanotubes. Each one is a hollow, cylindrical structure like a drinking straw, but with a diameter of mere billionths of a metre.
It has been suggested that airborne nanotubes could be inhaled deep into the lungs and that our body's defence mechanisms would find it difficult to clear these needle-shaped foreign objects.
To address this issue DIT looked at the impact of nanotubes on human cells in the lab, a project funded through its internal team research scheme.
PhD students Eva Herzog and Alan Casey grew human lung cells in the lab and exposed them to varying doses of carbon nanotubes, looking at the physical and chemical inter-reactions. But the nanotubes were so reactive that they interacted with protein in the liquid food in which the cells were growing. The nanotubes also mopped up the organic dyes that the scientists were using to assess the healthiness of the cells.
When the DIT group corrected their experiments to allow for the playfulness of the nanotubes, they found the news was good. Realistic exposure doses of the carbon nano-particles did not appear toxic to the lung cells, according to Dr Davoren. In addition, the electron microscope indicated that the nanotubes did not enter the cells. "I'm glad to report we found very little toxicity," she says.
Her group has now started looking at the potential environmental impact of various nanomaterials on cells from freshwater species in the lab. So far, the results are again showing little toxicity, Dr Davoren says.