THE SOS-CHROMO-SPOTTEST - EVALUATION OF A SHORT-TERM TEST FOR THE DETERMINATION OF GENOTOXIC COMPOUNDS IN CONTAMINATED ENVIRONMENTAL-SAMPLES

To evaluate the sensitivity of the SOS-Chromo-spottest towards genotoxic compounds 5 reference chemicals (4-nitroquinoline-1-oxide (4-NQO), methylmethansulfonate (MMS), 2,4,7-trinitro-9-fluorenone (TNF), sodium azide (SA) and daunomycin (DM) were tested by 3 different agar plate media (STA-plates: synthetic media containing Xgal, B-plates: synthetic media containing 1% lactose and bromocresolpurple, C-plates: 1% lactose bromocresolpurple media containing complexe nutrients). Even 1 ng of 4-NQO showed genotoxic effects by using STA-plates. The threshold value for MMS was 80 nl, for TNF 160 ng and for DM 80 ng. Similarly the spottest with B-plates gare positive results, but the sensitivity of this test procedure was 80 to 250 times lower than the STA-plate test. The C-plate test only reacted with high amounts of 4-NQO (1000 ng). Therefore, the SOS-chromo-spottest with STA-media described by Quillardet and Hofnung seems to be a sufficient procedure to detect genotoxic compounds in contaminated environmental samples directly without previous extraction procedures. The simpler B-plates can be used to examine the genotoxicity of certain compounds like industrial or household chemicals where the genotoxicants can be expected to be present in high doses.