Heavy metals such as lead, cadmium, chromium etc are environmental contaminants. They are also known today as human and animal carcinogens. Objectives: The aim of the study was to evaluate the genotoxic and biochemical effect of feeding rat with fish obtained from heavy metal contaminated water bodies in Lagos, Nigeria. Methods: DNA damage was investigated using DNA lading assay, while heavy metals and antioxidants were analyzed from fishes obtained from contaminated water bodies. Results:

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... was fragmentation of blood chromosomal DNA in rats fed with heavy metal contaminated fish, while in the control and zinc supplemented group, there was no fragmentation. Heavy metals were detected in the tissues and serum of exposed rat, while the activity of the serum catalase and reduced glutathione significantly decreased. Conclusion: The consumption of heavy metal contaminated fish resulted in DNA fragmentation and its deposition in the rat tissue. Zinc supplementation prevented the degradation of DNA and potentiated antioxidant activities. Lagos Lagoon in Nigeria is the largest lagoon system in the West African Coast, covering 208km 2 . The Lagoon is an open tidal estuary and it is fed in the North by Ogun River, Majidun , Agoyi and Ogudu Creeks. In the South margin, we have Five Crowries, Badagry Creek while in the East, we have Lekki and Epe Lagoons [19]. Fish Sampling and Analysis Two markets were selected for the purchase of the fish samples: Makoko market-close to Makoko water site of the Lagos Lagoon. Carter Bridge market-close to Carter Bridge site of the Lagos Lagoon. This is also known as Gbogbaniyi market, Lagos. The fish samples (Sarothederon melanotheron) were bought and taken to the laboratory where they were cleaned, identified, weighed, oven dried and grounded to powdery form. Animal Study 2.3.1. Experimental Animals Twenty-one albino Sprague-Dawley rats (190g + 6.27) were obtained from the Laboratory Animal Centre, College of Medicine, University of Lagos, Lagos State, Nigeria. They were randomly divided into four as follows: Group A, B, C and D. Feed:The rats were fed with rat chow and water ad libilum. The commercial rat chow manufactured by Pfizer Livestock Feeds, NIG., PLC, Ikeja, Lagos State, Nigeria, was used for the study.