Nanoplastics are particles that comprise various polymers (e.g. PET – Polyethylene terephthalate, PS – Polystyrene). Depending on the definition used they are less than 1 μm or less than 100 nm in size, respectively. Thus, the term nanoplastics does not describe a uniform material. It is important to distinguish between primary and secondary nanoplastics.
Primary nanoplastic particles are intentionally produced and used in various products, such as cosmetics, washing powders, as well as in research and diagnostics. They are often of a defined size or size distribution and usually consist of only one polymer type for a given application.
Secondary nanoplastics are formed in the environment, especially in rivers and oceans, by fragmenting larger pieces of plastic. These are released through the improper disposal of waste into the environment where they are decomposed by the influence of sun, wind and waves into even smaller pieces. After so-called meso- and microplastics emerged from the large pieces, these particles disintegrate into even smaller nanoplastics. Depending on the composition of the waste, nanoplastics consist of a mixture of different polymers.
