Abstract
We measured Perfluorocarboxylates (from C5 to C14) and perfluorosulfonates (CS4, CS6, , CS7, CS8 and CS10) in the tap water collected in 2011( from August to September) from six points in Osaka and Hyogo. The results were compared with the data of tap water collected in 2007. These results of the tap water were also related to those of the river water sampled in 2010 and 2003. In the tap water collected in 2011, C5~C12, and CS4, CS6, CS7 and CS8 were detected. Among them, the geometric mean concentrations were more than 1 ng/L for C8, C9, CS8 and C6, and they were 6.0, 4.1, 3.6, and 2.0 ng/L respectively. In the tap water from 6 points in Osaka and Hyogo collected in 2007, C8, C9, CS8,C7 and C6 showed high concentrations and the mean concentrations of these PFAA were 9.3, 2.1, 1.5, 1.1 and 0.58 respectively.
Thus, the C8 concentration decreased to 65%, and C6 increased about 3.4 times during this 4 years.
The national average concentrations of C8, CS8 and C9 in the tap water collected in 2007 were about 20% of the corresponding concentrations in the river water collected in 2010, while that of C6 was 3.4%. The average concentration of C6 in Kinki was about fifteen times as high as the national average, and the concentration ratio of C6 between the tap water and river water in Kinki was as low as 2.3%.
These results suggest that the release of C6 began recently.
