Danger Dust

Tiny shards of plastic called microplastics have been detected accumulating in human brains, but there is not yet enough evidence to say whether this is doing us harm, experts have said.

These mostly invisible pieces of plastic have been found everywhere from the top of mountains to the bottom of oceans, in the air we breathe and the food we eat. They have also been discovered riddled throughout human bodies, inside lungs, hearts, placentas and even crossing the blood-brain barrier.

The increasing ubiquity of microplastics has become a key issue in efforts to hammer out the world's first plastic pollution treaty, with the latest round of UN talks being held in Geneva next week.

The effects that microplastics and even smaller nanoplastics have on human health is not yet fully understood, but researchers have been working to find out more in this relatively new field.