GENTOXOCITY OF BLUE RAYON EXTRACTS FROM RIVER WATERS USING SISTER-CHROMATID EXCHANGE IN CULTURED-MAMMALIAN-CELLS

Using cultured Chinese hamster lung (CHL) cells, sister chromatid exch ange (SCE) assays were carried out with blue rayon extracts recovered at seven sampling locations from the Katsura, Nishitakase and Kamo Riv ers, tributaries of the Yodo River, in Kyoto City, Japan. The downstre am extracts of wastewater treatment plants showed higher SCE frequenci es than the upstream extracts both with and without metabolic activati on, suggesting that the effluents from wastewater treatment plants wer e the possible pollution sources of genotoxic chemicals in the rivers. The results show the possible use of SCE in CHL cells for the monitor ing of genotoxicity of blue rayon extracts from river waters. In addit ion, simultaneous treatment with sodium thiosulfate significantly redu ced the frequencies of SCE induced by blue rayon extracts.