Investigation on the Genotoxicity of Mercuric Chloride to Freshwater
Clarias gariepinus
Shahid Mahboob*, Hmoud Fares Alkkahem Al-Balwai,
Fahad Al-Misned and Zubair Ahmad
Department of Zoology, College of Science, King
Saud University, P.O. Box 2455, Riyadh-11451, Saudi Arabia *Corresponding author:
shahidmahboob60@hotmail.com
Abstract
The cytogenetic effect of heavy metal was studied
in Clarias gariepinus using the
micronucleus test, chromosomal aberrations and sister chromatid exchange. The
fish were kept separately and treated with four different concentrations of
mercuric chloride for a period of 7 days. For the micronucleus test blood
samples were obtained from the caudal vein. The mean micronuclei frequencies
were recorded as 0.20, 0.25, 0.50, 0.65 and 0.79 in controls and 1.0, 2.0, 4.0
and 6.0 ppm in groups treated with mercuric chloride, respectively. Kidney
tissues were used for in vivo chromosome preparation. The mean
frequencies of cells with chromosomal aberrations were 0.21, 0.32, 0.49, 0.70
and 0.97 in the control and 1, 3, 5 and 7 ppm in groups treated with mercuric
chloride, respectively. Similarly, the mean frequencies of sister chromatid
exchange were recorded as 0.10, 0.28, 0.47, 0.58 and 0.64 in controls and 1, 3,
5 and 7 ppm in groups treated with mercuric chloride, respectively. The findings
of present experiment suggest that HgCl2 caused genotoxic effects in
fish.