Hard on the heels of the microplastic beads being identified as dangerous — and hopefully banned world-wide in cosmetic products within a year or two — comes news of yet another type of highly egregious micro material.
This time it is inhaled rather than being eaten and diffuses directly from the nose into brain tissue. The warning comes from Prof Barbara Maher and her research team at Lancaster University after analysing the brain tissue of 37 people aged from 3 to 85 who lived and died in Mexico City — a notorious air pollution hotspot — and some other high traffic places including Manchester.
These microbeads are of iron oxide — particles burned away from the steel inside petrol and diesel engines. Maher’s lab has established that there are millions of these particles in every gram of brain tissue. These are dangerous not only because of the ‘gritting’ effect mentioned yesterday but also because they are magnetic. What effect may they be having on the electronic transmission of brain neurons? Could this form of pollution be implicated in Alzheimer’s or other neurodegenerative diseases?
No one knows the full effect yet but this is why an admittedly small sample has already been given prominence by publication in the Proceedings of the National Academy of Sciences. We can be sure that further funding for such important research is already being laid on. Quite besides the known, and rising, effects of ignition engines — deaths from asthma particularly — all this is yet more reason why land transport must be electrified as soon as possible.