Organophosphate esters (OPEs) that are widely used as additives in industrial products

have been monitored ubiquitously in environmental media. With the health hazards

and ecological risks caused by OPEs being attracted more and more attention, screening

toxicity mechanism was essential for risk assessment. In this study, Photobacterium

phophorium was employed to test the acute toxicity of OPEs. Integrating toxicity test and

molecular dynamics (MD) simulation, we calculated the binding affinity between OPEs

and n-octanol (C8H18O)/ phospholipid bilayer (DPPC) to further explore the mechanism

of toxicity. Good correlationship between the median effective concentration (EC50)

of OPEs and binding affinity was found. Binding affinity of selected OPEs with the

C8H18O/DPPC presented similar tendency. The mode of action (MOA) for OPEs to Pho

tobacterium phophorium was shown that tris (1, 3-dichloro-2-propyl) phosphate (TDCP)

belonged to reactive mechanism, triphenyl phosphate (TPhP) and tris (2-butoxyethyl)

phosphate (TBEP) belonged to narcosis mechanism. It was proposed a creative method

to quickly evaluate toxicity mechanisms of organophosphate esters by integrating the

toxicity test and MD simulation, which could be an alternative methodology to obtain

toxicity mechanism without using model organisms.