1993 Volume 30 Pages 227-234
FADU (Fluorometric Analysis of DNA Unwinding) is one of the most simple and sensitive methods to detect DNA strand breaks. We tried to apply this method as a short-term test which detects DNA-damaging environmental agents. An SV40-transformed human fibroblast cell line WI38-VA13 was used, and the oliginal FADU protocol was modified in this study. DNA strand breaks induced by physical and chemical carcinogens such as γ-rays, ultraviolet light, MNNG, 4NQO were detected efficiently by using the modified protocol. We also tried to detect DNA strand breaks caused by the effluent of a waste water treatment plant. About 5.6 strand breaks per 108 base pairs were induced when cells were exposed for 1 hr to water sample which was concentrated 200 fold. This represents DNA damages equivalent to approximately 11.2 strand breaks per average human chromosome. We conclude that the FADU assay using VA13 human fibrobrast cells is useful for detecting DNA damaging substances in the environmental water.
