The risk to humans posed by the use of nano wires remains a hot topic that’s generating fierce discussion between scientists and physicians. I believe that nano wires could present some potentially dangerous health risks if they are inhaled. There isn’t any conclusive evidence yet as to whether or not they are dangerous. But when it comes to industrial health hazards, it’s best to proceed with extreme caution.
Researchers at Lund University in Sweden have successfully performed experiments involving the injection of nano wires into brains—rat brains, that is. In the future, scientists say, it will be possible to insert nanoscale electrodes into the brain to study learning and memory functions as well as to treat patients suffering from chronic pain, depression, and diseases such as Parkinson’s.
But what would happen if one of the nano wires broke from its connections and drifted into the brain? The scientists at Lund University investigated this worst-case scenario by injecting nano wires into rat brains. Astonishingly, the results showed that certain brain cells called microglia took care of the wires.
“We studied two of the brain tissue’s support cells: on the one hand, microglia cells, whose job is to ‘tidy up’ junk and infectious compounds in the brain, and, on the other hand, astrocytes, who contribute to the brain’s healing process,” said researcher Nils Danielson. “The microglia ‘ate’ most of the nano wires. In weeks six and 12, we could see remains of them in the microglia cells.”
So it does seem that in the case of rodents, the brain does have some protection mechanisms against the infiltration of nano wires. While nano wires and nano tubes offer enormous potential in electronics, I still maintain that people working with nano products could be at risk of inhalation-related disease that can in some circumstances take years to present itself.
Particularly relevant to this viewpoint is the size, shape, weight, and airborne characteristics of nano material. If a particle does enter the lungs, it is unlikely that the macrophages—the protective cells that remove unhealthy tissue in the lungs—would be able to deal with it once it had penetrated the lung surfactant.
So whereas it was good to read that microglia cells in rat brains were able to deal with infiltrating nano products, research has to go a lot further before we are assured that organs in the human body can follow the rats’ example.