Perfluorooctane sulfonate contamination of drinking water in the Tama River, Japan: estimated effects on resident serum levels.

In a previous study (Saito et al. submitted for publication 2002), we showed that PFOS contamination in surface waters has occurred all over Japan: concentrations were found to be in the range of 0.2-157 ng/L with a geometric mean (geometric standard deviation) of 2.37 (4.13) (n=126), These levels were much lower than those found in the Tennessee River (Hansen et al 2002). However, we found that the middle stream of the Tama River was exceptionally heavily contaminated with PFOS. There could be some concerns about this Tama River PFOS contamination because a drinking water intake site is located in the Tama’s lower stream.