We see plastic litter on beaches and streets, but much of the plastic problem is made of pieces you don’t notice at first glance. When bottles, tires, paint, or synthetic clothing break down, they fracture into fragments that behave very differently from the original object: some sink into sediments, some float and travel long distances, and the smallest particles can move through air and pass into living tissue. How small are we talking? Microplastics are generally defined as fragments smaller than 5 millimetres (5,000 microns) and extending down into microscopic and nanoscale sizes; many researchers call particles smaller than 1 micron “nanoplastics.” To give that some weight: an average human hair is about 70–80 microns across and a grain of table salt is roughly 60 microns, so the tiniest particles scientists measure are dozens to thousands of times smaller than items you touch every day. The visualization below, created by VisualCapitalis , shows how small microplastics ar...
Exploring the Planet & Ourselves