mikroplastiks

Microplastics are plastic particles smaller than five millimeters in size. They are typically divided into primary microplastics, manufactured at small sizes such as microbeads used in cosmetic products and plastic pellets, and secondary microplastics, produced by the breakdown of larger plastic items through weathering and abrasion.

Environmental presence and fate: Microplastics have been detected in oceans, rivers, soils, sediments, and even the atmosphere. They are transported by water currents, wind, and animal movement and can accumulate in ecosystems. They can also adsorb hydrophobic pollutants and metals, potentially transferring contaminants to organisms.

Sources: Major sources include primary microplastics such as cosmetic beads and plastic pellets; synthetic textile fibers shed during washing; tire wear from road traffic; litter and improper waste management; and fishing gear. Wastewater and stormwater systems are routes for microplastics to enter the environment.

Biological and health aspects: Many marine and freshwater organisms ingest microplastics, which can cause physical harm or reduce feeding and energy intake. The fate and effects of microplastics in humans are not fully established; exposure occurs through seafood, drinking water, and air, but health risks are still under investigation.

Measurement and regulation: Researchers report concentrations as particles per liter or per kilogram of material; unit choices and methods vary, complicating comparisons. Methods include microscopy, spectroscopy, and pyrolysis-based approaches. Policy responses include reducing plastic use, improving waste management, filtering out microplastics from washing and wastewater, and restricting microbeads in cosmetics; many jurisdictions have adopted such measures.

Knowledge gaps: Standardized sampling and analysis, long-term ecosystem and health effects, and fate in soils and air require further study.