Multimedia fate and transport simulation of perfluorooctanoic acid/perfluorooctanoate in an urbanizing area

Strong global demand leads to significant production of fluoropolymers (FP) in China which potentially release large quantities of perfluorooctanoic acid/perfluorooctanoate (collectively called PFOA/PFO) to the environment. Modelling the fate and transport of PFOA/PFO provides an important input for human health risk assessment. Considering the effects of urbanization and existing forms of PFOA/PFO, this study used the modified multispecies Berkeley-Trent-Urban-Rural model to simulate the transfer behavior of PFOA/PFO in the Bohai Rim, China. Spatial distributions of PFOA/PFO emissions during the year 2012 for the study area were illustrated. About two thirds of the total amount of PFOA/PFO was estimated to be released into fresh water, and the total releases to rural areas were 160-fold higher than those to urban areas due to the location of fluorochemical industrial parks. The simulations predicted that hydrosphere was the fate of PFOA/PFO, followed by soil and vegetation, which was consistent with field data. The highest PFOA/PFO concentration was modeled in the Xiaoqing River basin with a value of 32.57mug/L. The PFOA/PFO concentrations in urban soils were generally higher than those in rural soils except for grids 1, 3 and 46. In addition, it was estimated that the total flux of PFOA/PFO entering into the Bohai Sea was 24.57 ton/year, 100-fold higher than that of perfluorooctane sulfonates (PFOS).