Microplastics are plastic particles smaller than 5 millimetres. Primary microplastics are manufactured at that size, such as microbeads and industrial pellets. Secondary microplastics form when larger plastic items break down in the environment.
Sunlight, heat and abrasion slowly fragment littered and dumped plastic into ever smaller pieces, which spread through soil, rivers, oceans and the air, and have been found in food, drinking water and the human body. Other major sources are tyre wear and synthetic textile fibres. Plastic that is collected and recycled does not get the chance to fragment in the open, so effective waste management is one of the most direct ways to reduce microplastic pollution, along with preventing losses of pellets and flakes during handling.
