Abstract
A survey study for estrogens, nonylphenol (NP) and its precursors (nonylphenol ethoxylates and nonylphenol ethoxy acetates) was conducted for water and sediment of the Kamo River and its inflow waterways. 17β-estradiol (β-E2), estrone (E1) and 17α-estradiol were detected in river water and sediment up to the levels near their highest concentrations detected in the nationwide surveys. β-E2 concentration in water at almost all sampling sites was higher in winter and spring and lower in summer and autumn, suggesting more active decomposition of β-E2 by microorganisms at high water temperature. E1 showed the largest contribution to estrogenic activity of water among the examined compounds. However, NP accounted for a large part in estrogenic activity of sediment. The average emission loads of β-E2 and E1 estimated in the Kamo River basin were 12 and 75 nmol/cap/day, respectively. These values corresponded to a comparatively high amount estimated in the effluents from sewage treatment plants.
