Clastogenicity of Quinoline and Monofluorinated Quinolines in Chinese Hamster Lung Cells

Quinoline and four monofluorinated derivatives of quinoline (FQ's) were tested for their clastogenicity in a Chinese hamster lung (CHL) cell line using chromosomal aberration (CA) and micronucleus (MN) tests. Quinoline and all the fluoroquinolines, 3-, 5-, 6-, and 8-FQ, induced CA in the presence of the metabolic activation system. However, the clastogenic property was altered by fluorine-substitution. 3-FQ showed reduced cytotoxicity and clastogenicity. It was positive only at a higher dose than the other compounds. 6-FQ was as cytotoxic and clastogenic as quinoline when tested in the lower dose range (less than 0.075 mg/ml). 5-FQ and 8-FQ were only moderately clastogenic in the CA test although their toxicity was similar to that of quinoline. The MN test showed almost the same tendency in clastogenicity as the CA test, except that 8-FQ showed a negative result. These results demonstrate that fluorine-substitution can modify the clastogenicity of quinoline, probably through interference of the metabolic activation.