Adsorption behavior of ZIF-67 to bisphenol compounds affects combined toxicity on Photobacterium phosphoreum.

ZIF-67, as a typical MOF material, is considered a new type of high-potential adsorbent due to its ample surface area and tunable surface chemistry, which has the potential to interact with other contaminants in unforeseen ways, resulting in combined toxicity. To further elucidate this possibility, we chose typical bisphenol compound (BP) which is widely used in commercial manufacturing, to explore the combined toxicity with MOF. MOF showed a high adsorption capacity for BPAF (> 80 %) and the weakest adsorption capacity for BPA (< 10 %), and DFT confirmed the different interaction strengths of MOF for BPs. The difference in adsorption capacity for BPs resulted in different amounts of free BPs, contributing to combined toxicity. Based on flow cytometry and TEM, the results showed that membrane damage was reduced and the ability of ZIF-67 to enter the cell was decreased in the low-concentration ZIF-67 mixing group, and the ability of ZIF-67 to enter the cell was increased in the high-concentration ZIF-67 mixing group, and the membranes were severely damaged. RT-PCR and biochemical indicators measurements helped to explain the underlying toxicity mechanism. This study is of practical significance for the development of environmental guidelines for mixed contaminant effects and accurate risk assessments.