Cytogenetic Analysis of Zebra Fish (Danio rerio) Exposed to Water Samples collected from Different Areas of Pampanga River

Toxicity in different bodies of water is widespread due to the presence of both genotoxic and cytotoxic components such as heavy metals that originate from different sources, in which anthropogenic factors play a major causative role. Due to these problems, biomonitoring was developed to keep things in check and to know firsthand the danger of these toxic substances in living organisms. This study aimed to assess the level of toxicity of water samples collected from Pampanga River. Three specific stations were chosen: Macabebe (T1), Sulipan (T2) and Candaba (T3). Zebra Fish ( Danio rerio ) were exposed to these collected water for seven (7) days along with three other controls: T0 (Zebra Fish exposed to Purified Water), T+1 (Zebra Fish exposed to water with 1ppm Copper) and T+2 (Zebra Fish exposed to water with 1ppm Lead). Three zebra fish were exposed to different treatment for 7 days. Gills were collected from the specimen and subjected to cytogenetic procedures to acquire c-metaphase cells. Cytogenetic analysis revealed the occurrences of chromosomal abnormalities such as Ring Chromosome, Chromatid Gap, Chromatid Break, Endoreduplicated Chromosome and Chromosome fragments in c-metaphase. Analysis of variance revealed the significant occurrence of chromosomal abnormalities in each station. Duncan multiple range test shows that the two positive controls (T+1 and T+2) produced the highest means of chromosomal abnormalities followed by the three sampling stations (T1, T2 and T3). The (T0) negative control did not produce any occurrence of chromosomal abnormalities. Based on the results T+2 (7.667) has the highest occurrence of chromosomal abnormalities followed by T+1 (6.667), T3 (3.33), T1 (2.333) and lastly, T2 (2.000). Results suggest that the water samples from the three stations are able to produce chromosomal abnormalities indicating the presence of DNA intercalating agents in Pampanga River.