Microplastics in aquatic environments: a growing, unresolved concern

The global rise in plastic demand and production, combined with the significant amount of plastics found in municipal solid waste, has led to the ubiquitous occurrence of microplastics (MPs) in the aquatic environment. This review examines the existing information on the origin, behaviour, fate, and effects of MPs on living organisms and the environment. In aquatic ecosystems, the reported high concentrations of MPs potential threat to the exposed organisms, causing blockage of the intestinal tract, alterations in feeding and digestive habits, injury, and death. Both fresh and aged MPs interact with different components of the aquatic ecosystem, leading to changes in their behaviour and bioavailability. Additionally, MPs often serve as vectors for sorbed pollutants and the chemicals leaching from their polymeric chains, enhancing the transportation of contaminants within the aquatic environment and to predators. With the current rate of plastic production and use coupled with the lack of proper waste management policies in many countries, the worries about environmental MPs have increased in recent years. Hence, a better understanding, continuous monitoring, and plastics management methods and waste control plans are crucial to address the issue of MPs in the environment.