Perfluorinated compounds (PFCs) in Yodo River system,Japan

摘要

There is increasing concern about occurrences of perfluorinated compounds (PFCs) in thenenvironment due to their persistent, bioaccumulation, and potentially toxic effects. Weninvestigated contamination of 11 PFCs (C4-C12) in the Yodo River system, which is a major sourcenof drinking water for more than 11 million people of Kansai region in Japan. PFCs were detectednin higher concentration even exceeding more than 1000 ng/L in some cases. Composition profilenof total PFCs concentration showed that PFOS, PFHxA, PFOA, and PFNA were occurringndominantly in the river system. PFOS and PFOA concentration were nearly proportional to anprevious study in the same river system, indicating continuous sink of the compounds into thenriver system. Although discharge of PFCs from wastewater effluents at upstream could be one ofnthe major point sources, concentration did not exceed 29.4 ng/L at the downstream of main YodonRiver, possibly, due to dilution effects. Total mass load of PFCs in mainstream of Yodo River wasnestimated 451.7 g/d based on observed river discharge and PFCs concentration. Results showednthat Yodo River system could have a unique upstream-downstream linkage of PFCs contaminationnand the river could be a continuous pathway of PFCs exposure to the people of Kansai region.