Abstract
Main objective of this study was to understand the occurences of total organic fluorine (TOF), the component perfluorinated compounds (PFCs) and their formation potentials (PFC-FPs) in the Lake Biwa – Yodo river basin. Total of 68 water samples (9 lake water samples, 45 river water samples and 9 wastewater treatment plant (WWTP) effluents) were collected during August to October 2016. TOF was analyzed by Combustion Ion Chromatography and PFCs and PFC-FPs were analyzed by LC-MS/MS. As a result, 1) TOF concentrations in 67 samples were detected at more than limit of detection (32 ng-F/L). 2) The ratios of Σ15 PFCs in TOF concentration were not significantly different among each water sample type (lake water, river water and WWTP effluent) and average value was 22%. 3) TOF concentrations were detected higher in the order of WWTP effluent, river water and lake water on average (748, 458, 175 ng-F/L, respectively) in the Lake Biwa – Yodo River basin while it was detected at 115,138 ng-F/L in effluent from a single WWTP (N-WWTP) in the Ai river basin, suggesting that there was a specific point source. 4) TOF and PFC-FPs loading from N-WWTP were calculated as 30,740 g/day and 8,807 g/day respectively, which were 2.2 and 3.2 times higher than the loading at the downstream of Yodo river where the flowing water flux was 47 times higher. It was suggested that unknown PFCs relatives were discharged from N-WWTP.
