Abstract
Seasonal and basinal variations of direct mutagenicity of Nakdong river in Korea, were investigated by Ames test. Nakdong river is 512.5 km from middle of Korea to Pusan and the river water is the source of water supply of Taegu and Pusan cities. Semiconductor, dye and food plants and domestic wastewater arc inflowed to upper and middle stream of the river. Dissolved substances in water were recovered with XAD-2 resin adsorption method.
The adsorbed substances were eluted with hexane, dichloromethane and methanol in this order. The mutagenicity of each fraction was estimated by Ames test without S9 mix. The samples in May, 1991 showed high mutagenicity with TA98 strain while no mutagenicity with TA100 one, suggesting that Nakdong river is polluted by frame-shift type direct mutagens. To estimate the origin of mutagenicity in this river basin, river waters were taken from 5 stations of Nakdong river, 1 station of Kumho river and 1 station of Jinchun stream, tributaries of Nakdong river, for one year from May, 1995. Similar results to May, 1991 were observed showing pollution with frame-shift type direct mutagen. The present results suggest that wastewater from dye and food plants located in the tributary may contribute to the pollution of direct mutagenicity in Nakdong river.
