Evaluation of the Effects of (NO3)2Pb on Oreochromis niloticus (Pisces, Cichlidae) by Means of Cytogenetic Techniques

Abstract

SummaryWater sources contamination is a major concern subject, as well as the environmental presence of a widely diffuse pollutants, as lead. Evaluation of xenobiont effects on genetic material have as a main objective to determine the relationships between genotoxicity and initiation of neoplasic and teratogenic events and genetic diseases. This evaluation can be done by means of several bioassays. Fishes are suitable bioindicators for the detection of aquatic pollution. In this study Oreochromis niloticus specimens were exposed to 2 different concentrations of (NO 3 ) 2 Pb. Chromosome alterations in structure and number, micronucleus test and nuclear morphology alterations were analysed in chromosome preparations and blood smears of exposed and unexposed fishes. Results showed significant differences in the frequency of micronucleus and chromosome alterations between distinct treatments. These data suggest a genotoxic effect of (NO 3 ) 2 Pb.

DNA damage in the kidney tissue cells of the fish Rhamdia quelen after trophic contamination with aluminum sulfate

“…In fish, different CA types have been described following exposure to metal contaminants, such as lead and tributyltin ( Cestari et al , 2004 ; Ferraro et al , 2004 ., Ale et al , 2004 ; Ramsdorf et al , 2009a ), leading us to suggest that the decondensation of the telomeric regions of the chromosomes may have occurred due to structural modifications to the proteins involved in DNA compaction, thus making the DNA more susceptible to breaks. This may have also caused the chromatid breaks.…”

“…In fish, the hematopoietic tissue found in the kidney is customarily used to obtain mitotic chromosomes ( Bertollo et al. , 1978 ) and also to assess chromosomal abnormalities when evaluating genotoxicity ( Ale et al , 2004 ; Cestari et al , 2004 ; Ferraro et al , 2004 ; Ramsdorf et al , 2009a ).…”

Study of the frequencies of erythrocyte abnormalities as in situ biomarkers of genotoxic risk of chemicals in special fish stock in water supply reservoirs

“…Manson's solution was used to detect basophilic stippling, and Perl's Prussian blue staining was used to determine the pigment content and Feulgen stain to identify chromosomal material or DNA. For each individual, erythrocytes were examined under 1000× magnification and scored into categories, most of which were evaluated for their use as pollution bioindicators using the MNT and the nuclear erythrocyte abnormalities test in erythrocytes (Ale et al., 2004; Ali et al., 2008; Al‐Sabti, 1986a, 1986b; Anbumani & Mohankumar, 2011; Azevodo et al., 2012; Baršienė et al., 2006; Braham et al., 2017; Carrasco et al., 1990; Das & Nanda, 1986; Gomes et al., 2015; Göney & Gazeloglu, 2020; Hussain et al., 2018; Ivanova et al., 2016; Jiraungkoorskul et al., 2007; Kousar & Javed, 2015; Matsumoto et al., 2006; Metcalfe, 1988). The criteria for scoring MN and binuclei (BN) were adapted from Fenech et al., 2003; the diameter of MN should be less than one‐third of the main nucleus.…”