The Comet assay detects recent lesions
that can be repaired, such as breaks and alkali-labile
sites, while the MN test detects non-repairable damage,
such as clastogenic and aneugenic lesions (Villela et al.,
2007). Our findings show that the compounds present in tobacco
leaves were genotoxic and mutagenic in H. aspersa.
The slight time-dependent increase in DNA damage (seen
in the Comet assay) in untreated snails can be explained by
animal stress. Other reports have described similar results
for controls (Villela et al., 2007). Since the frequency of
MN seen here in the control group was within an acceptable
range, our results can be considered reliable.