Many studies have shown that plastics and especially microplastics are present in all environmental compartments, including sediment, soil, water column and surface layers, in marine/freshwater and terrestrialecosystems.Wherever we look, we have the possibility of encountering plastic.Some of the most probable sources of plastics are mismanaged plastic wastes, microbeads, textile fibers, car tires etc.
The microplastics are divided into two main groups according to their origin. These are primary and secondary microplastics. The distinction between primary and secondary microplasticsis based on whether the particles wereoriginallymanufactured to be that size (primary) or whetherthey have resulted from the breakdown of larger items(secondary).
1) Primary Microplastics
Primary microplastics are plastics produced directly in microplastic form. This type of microplastics include industrial ‘scrubbers’ used to blast clean surfaces, plastic powders used in moulding, micro-beads in cosmetic formulation, and plastic nanoparticles used in a variety of industrial processes. In addition, spherical or cylindrical virgin resin pellets, typically around 5 mm in diameter, are widely used during plastics manufacture and transport of the basic resin ‘feedstock’ prior to production of plastic products.
2) Secondary Microplastics
Secondary microplastics are plastics that are formed as a result of fragmentation of large sized plastic materials by various factors (physical, chemical, biological). Fragmentation can happen during the phase of products such as textiles, paint and tyres, or once the items have been released into the environment.