Simulation of Transport Fate of PFOS and Precursors in the Yangtze River Delta
Perfluorooctane sulfonate acid(PFOS)is of great concern as a new contaminant.In this study,CoZMo-POP 2 fugacity model was used to simulate and calculate emission,fate distribution,and transfer processes of PFOS,N-EtFOSA,N-MeFOSA,N-EtFOSE and N-MeFOSE in Yangtze River Delta during 1988-2022.The results showed that cumulative emissions of PFOS,N-EtFOSA,N-MeFOSA,N-EtFOSE and N-MeFOSE in the study area were about 26t,2.5 t,0.16t,7.8 t and 5.9 t,respectively.The model reliability was verified by fact that residuals of modeled and measured concentrations of PFOS in soil,freshwater,and sediment were within 1 log unit.According to the result of sensitivity analysis,temperature and partitioning coefficients were key parameters affecting pollutant concentrations.When environmental system reached equilibri-um,the largest sink of PFOS was coastal water,accounting for approximately 79%of total amount remaining in the system.The transfer from fresh water to estuarine water and estuarine water to coastal water were the main PFOS transfer routes between media,accounting for 53%of total transfer.Flow to the outside is most important output pathway for PFOS.The largest sink of N-EtFOSA,N-MeFOSA,N-EtFOSE and N-MeFOSE were soil,accounting for approximately 99%,98%,91%and 97%of total amount remaining in the system,respectively.Degradation was the main output pathway for N-EtFOSA,N-MeFOSA,N-EtFOSE and N-MeFOSE.This study simulated the transfer and fate of PFOS and PreFOS in the environmen-tal multimedia of Yangtze River Delta,which could provide a scientific basis for its pollution control and ecological risk assessment.
perfluorooctane sulfonate acid(PFOS)Yangtze River Deltafugacity modeltransfer and fate