For a long time, it was thought that the human brain existed in splendid isolation from the rest of the body. The so-called blood-brain barrier, a special layer of cells, protects the brain from all manner of pathogens and harmful substances. However, we now know that the blood-brain barrier can be breached because small plastic particles have been found in the human brain.

New research has suggested that the blood-brain barrier has at least one vulnerable spot where microplastics may be able to get into the brain. This potential entry point was suggested by researchers at the Freie Universität Berlin and the University of São Paulo. It is in the nose, where there are special nerves, the olfactory nerves, that detect smells…

Eight out of the 15 brains studied had microplastics in their olfactory bulbs. However, these eight samples had only 16 microplastic particles between them, which is perhaps some comfort.

Those 16 plastic particles included fragments, spheres and fibres, and were made of polypropylene, nylon and other plastics. Some of the fibres could have come from clothing. This makes sense because laundering clothes made from synthetic fibres is a significant source of microplastics in the environment.