Decoding the interactions between microplastics, polyfluoroalkyl substances, and endocrine disruptors: sorption kinetics and toxicity

Abstract

Microplastics (MPs) present a direct threat to aquatic organisms while functioning as vectors for the mobilization of organic contaminants within aquatic environments. Furthermore, due to their extensive usage, per- and polyfluoroalkyl substances (PFAS) and endocrine-disrupting chemicals (EDCs) have emerged as significant global concerns due to their pervasive presence and substantial accumulation in aquatic ecosystems. Research to date has primarily focused on these contaminants in isolation, leaving the interactions and cumulative effects among MPs, PFAS, and EDCs (trifecta) relatively unexamined. We elucidate the probable interaction mechanisms among these three categories of contaminants and to analyze their combined toxicity, as well as the existing regulatory frameworks and policies applicable to them. Our findings indicate that the sorption of EDCs and PFAS onto MPs is predominantly governed by hydrophobic and electrostatic forces and is sensitive to various environmental parameters, including pH, salinity, temperature, and dissolved organic matter. The interactions among these contaminants are intricate, encompassing mechanisms such as cation-π bonding and biofilm formation, all of which influence the dynamics of sorption. The synergistic effects of MPs in conjunction with co-contaminants, such as PFAS and EDCs, exacerbate toxicity, promote bioaccumulation, and elevate health risks for both aquatic organisms and mammals, typically contingent upon factors such as exposure duration, dosage, and environmental conditions. In conclusion, we underscore that while significant advancements have been achieved, considerable efforts are still required to address regulatory deficiencies and to advance legislation aimed at mitigating the impact of persistent pollutants.