Abstract
The existence of linear alkylbenzene sulfonates (LAS), fatty acids and fats was investigated in the surface water and sediments of several Japanese rivers (the Tama, Ta, Kinu and Tenpaku River). The determination of LAS was carried out by Abbot's methylene blue method and reversed-phase high performance liquid chromatography (HPLC) with a fluorimetric detector. Fatty acids and fats were measured, after prelabelled of fatty acids (or fatty acids in fats) with 4-bromoethyl-7-methoxycoumarine (BMC), by a reversed phase HPLC with a fluorimetric detector. Methylene blue active substances (MBAS) were detected in all river water and sediments samples, while LAS was not able to be determined without the Tama and Ta River. The concentrations of LAS detected in the river water and sediments of the Tama River were trace-0.38 mg El-1 (trace-0.82 mg El-1 of MBAS) and 2.79-10.72 ppm (6.23-31.6 ppm of MBAS), respectively. The concentrations of fatty acids in river water and sediment were 0.005-0.052 mg El-1 and 7.7-426 ppm, respectively, and river sediments contained 8-19 ppm of fats. These fatty acids and fats were estimated to be derived from organisms such as algae and bacteria.
