INCHEM, 2012) can be explained by the extraction method
used. The highest frequency of damage was observed after
72 h, although a similar extent of damage was observed after
24 h. Argentin and Cichetti (2004) applied the MN test
to cultured mammalian cells treated with nicotine and observed
rapid induction of DNA damage in samples treated
for up to 72 h, with maximum levels observed after 24 h of
exposure. Nicotine caused a concentration-dependent increase
in DNA fragmentation, as assessed by the Comet assay,
in mini-organ cultures of human nasal epithelium,
indicating a direct genotoxic effect (Sassen et al., 2005);
similar findings have been reported for lymphatic tissue of
palatine tonsils and peripheral lymphocytes (Kleinsasser et
al., 2005).