Abstract: OBJECTIVE: A chromosomal aberration (CA) screening test was established using eight-well chamber slides without adopting complicated procedures and chemical agents in the traditional chromosomal aberration test in vitro. The validation of the protocol was conducted using several genotoxic chemicals with various mechanisms of action and non-genotoxic compounds. METHODS：Optimized conditions for the test procedure in which cells were treated with cyclophosphamide (CP) for 6 h (for the +S9 condition) and mitomycin C (MMC) for 24 h (for the -S9 condition) were investigated. And then five known genotoxic chemicals including benzo(a)pyrene[B(a)P]，2-aminoanthracene(2-AA)，methyl methanesulphonate (MMS)，ethyl methansulfonate(EMS)，etoposide(Eto) and two non-genotoxic chemicals including ampicilin sodium salt(AS) and sodium chloride(SC) were used in the sensitive and specific validation research under these conditions. RESULTS：The CA percentage of CP (6 h，+S9) and MMC (24 h，-S9) showed dose-dependent accumulation. In the validation tests，B(a)P and 2-AA were positive only in (6 h，+S9) condition while MMS，EMS and Eto showed positive results in both +/-S9 conditions. AS and SC were negative in both +/-S9 conditions. CONCLUSION： The chromosomal aberration test using eight-well chamber slides could be considered as a simple，rapid and effective method，which could be used in genotoxicity screening in the early research phase of drug development.

Key words: eight-well chamber slide, chromosomal aberration, screening