2007 Volume 30 Issue 6 Pages 309-315
In this study, we determined the concentrations of 29 polynuclear aromatic hydrocarbons (PAHs) and related oxidants (four kinds) in river, drinking and heated water samples. The composition of PAHs in drinking water differed from that of PAHs in river water, and the concentrations of dibenzofuran, fluorene, 9-fluorenone and antraquinone in drinking water were higher than those in river water. The total concentration of PAHs in drinking water in the neighborhood around a water purification plant was the same as that of PAHs in river water (the main stream). However, the total concentration of PAHs in drinking water supplied from water purification plants was higher in distant areas than in the neighborhood around the water plant. From to the concentrations and detection frequencies of PAHs in drinking water, those of dibenzofuran, fluorene, 9-fluorenone and antraquinone were the highest, whereas the PAHs showing the second highest concentrations and detection frequencies were naphthalene, biphenyl and phenanthrene. Furthermore, the total concentration of PAHs peaked during summer at 200-300 ng · l-1 and showed a trough at 10-30 ng · l-1. The total concentration of PAHs in drinking water collected from a specific district in the Tokyo metropolitan area was about 200 ng · l-1 during summer. Compared with unheated drinking water, the concentrations of individual PAHs, total PAHs and PAH oxidation products are decreased in drinking water that has been heated using an electric pot or a kettle. The daily intakes of total PAHs are estimated to be 20-60 ng during winter and 200-600 ng during summer for people who drink only 2000 ml of tap water, and 15-45 ng during winter and 150-450 ng during summer for people who drink 1000 ml of tap water and 1000 ml of heated water.
