The results of MN frequencies found in fish from the
different sampling sites were shown in Table 4. Fish from
agriculture drain, showed the lowest MN frequencies.
The highest MN frequencies were found at El Moheet
drain site. Values were statistically different among sites.
The results of this study confirmed the usefulness of
the erythrocyte micronucleus as a powerful monitoring
tool for detecting genotoxic agents in an aquatic
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environment. The detection of micronucleus (MN) in fish
helps us to know the status of water quality, the health of
species and potential risk [50]. Although there are a large
number of genotoxicity assays, only a relatively small
number have been used for field evaluation of domestic,
agricultural and industrial effluents on aquatic
ecosystems [51]. Pacheco et al. [52] noted that only field
studies based on the capture of wild specimens could
provide a definitive indication about the environmental
state and the ichthyic population’s health. MN test in fish
has the potential for detecting clastogenic substances in
aqueous media. Since teleost erythrocytes are nucleated,
MN has been scored in fish erythrocytes as a measure of
clastogenic activity. Various studies showed that the
peripheral erythrocytes of fish display a high incidence of
MN after exposure to different pollutants under field and
lab conditions [53].