How are microplastics formed?

Primary microplastics include microbeads, nurdles and fibres. These are manufactured as microplastics, that is as particles of 5mm or smaller ... Secondary microplastics are formed because of larger plastics breaking down. UV rays, wind and wave action causes plastic to fragment into millions of smaller pieces.

Microplastics are found especially in the marine environment they are usually less than about 5 mm in size.

The action of the following contributes independently or maybe collectively to it's formation;

UV radiation, plastic weathering from larger plastic products of cloths and nurdle, transportation, physical stress, fluctuating temperatures, salinity, littering of plastics, production spills, landfill waste choice, chemical formation of microbeads, wave actions ...