A Review of Organophosphate Esters with Different Functional Groups: Focusing on Microbial Degradation

Organophosphate esters (OPEs), characterized by diverse chemical substituents, have emerged as widely used flame retardants and plasticizers, replacing polybrominated diphenyl ethers (PBDEs) under global regulatory actions. However, due to their environmental persistence, bioaccumulation potential, and multiple toxic effects, OPEs are now recognized as emerging pollutants and have attracted extensive research attention. This review systematically compares structurally distinct OPEs in terms of their environmental occurrence, physicochemical properties, mobility, and biodegradation fate. We place special emphasis on recent advances in microbial degradation and enzymatic transformation pathways under both aerobic and anaerobic conditions, with a focus on key degrading strains, metabolic intermediates, and underlying mechanisms. Furthermore, factors influencing biodegradation rates (including compound structure, microbial community composition, and environmental variables) are comprehensively examined. By identifying critical research gaps and proposing future directions, this review aims to provide a scientific foundation for sustainable management and effective risk assessment of OPEs in the environment.