Perfluorinated Compounds in Tamagawa River Basin -Trend of Contamination and Mass Flow

Abstract

13 kind of Perfluorinated compounds (PFCs) in the mainstream of Tamagawa River and its inflows (tributaries, and effluents from Sewage Treatment Plants) were analyzed, and the loads of PFOS, PFOA and other 4 compounds were evaluated. The concentrations of PFOS and PFOA were found to be much lower than those of 2005 since 2009. This result indicates that the Stockholm Convention on Persisitent Organic Pollutants (POPs) and 2010/2015 PFOA Stewardship Program are effective. The cumulative load of PFCs that was accumulated in the inflows sequentially from Nagata Bridge, as the uppermost point in this study, closely resembled the measured load at each sampling point in Tamagawa River. These results indicate that PFCs were scarcely degraded, volatilized, during flow down the river. The ratio of PFCs with longer chain length such as PFUnDA and PFTrDA in sediment samples were much higher than those of water ones.