Introduction (summary)
Heavy metals are known to cause abundance of effects on all living organisms including fish (olsson,1996, Sorenson,1991).
The overall objective of study is to ascertain the level and quantum of genotoxic effects of cadmium chloride and arsenic trioxide  as compared to DW treated controls and also to find out if certain antioxidants like AA and ocimum can nullify the oxidative metabolism of these chemical by producing electrophilic metabolites.
Methodology
Somatic chromosomes were prepared as the conventional colchicine citrate flame drying technique( khudabukhsh ,1979) for both control and treated series.
For micronuclei  testing , the procedure of Schmidt(1976) was followed.
For sperm head anomaly, procedure of Manna and Biswas was followed, further followed by microscopic analysis.
Experimental set up was provided by taking
18 to 22gms fish, collected from local pond and then acclimatized in concrete vats maintained under similar conditions.
Conclusion
Maximum amelioration have been found at 48hr interval for cadmiumchloride  and arsenic trioxide induced genotoxicity, when treated conjointly with either ocimum or with ascorbic acid, in tilapia.
However both AA  and ocimum showed certain amount of genotoxicity when treated individually in the fish specimens.
The dose at which maximum amelioration could be found was noted, which was 0.02 percent for AA and 0.5 percent for ocimum.
The antioxidative property is mainly due to phenolic acid, flavonoids and anthocyanins present  in vitamin c and basil (ocimum).
Data format
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