What Does the “Trojan Horse” Carry? The Pollutants Associated with Microplastics/Nanoplastics in Water Environments

Plastic additives are intensively used in the plastic industry. Namely, plasticizers, flame retardants, stabilizers, and antioxidants have raised significant environmental concerns. These additives, characterized by relatively high toxicity and bioaccumulation rates, pose substantial risks to human health. When plastics break down into smaller fragments (i.e., micro/nanoplastics (MNPs)), these additives can be released into aquatic environments, where they may interact with other pollutants through various mechanisms, and multiple factors can affect such interactions. This can influence the occurrence of MNP-associated pollutants in water environments and further impact the environment and human health. Although MNP additives and their associated pollutants pose significant risks, research on their behavior and impacts remains limited. This review maps out the current understanding of MNP additives and associated pollutants, and identifies critical knowledge gaps, setting a foundation for future research directions that will further unravel the complexities of MNPs in water environments and their broader implications.