Bio-Accumulation of Heavy Metals in Aquatic Organism in Otamiri River in Owerri, Imo State, Nigeria

Abstract

Depending on a number of variables, heavy metals from both natural and anthropogenic sources may accumulate in fish bodies and heads in aquatic environments. This study intends to evaluate the degree of heavy metal bioaccumulation in Tilipia fish from the Otamiri river. A sample of dry tissue weighing around one gram was weighed, placed into polyethylene tubes, and treated with 8 ML of nitric acid and 4 ML of perchloric acid. An atomic absorption spectrophotometer was used to determine the presence of heavy metals in the fish tissues. The amount of heavy metals present in fish sections was listed as follows: Lead varies from 32.00-7.23mg/kg, and the greatest value was found in the fish head that was caught in the Otammiri River. Zinc ranges from 16.75 mg/kg to 17.13 mg/kg, with the highest value recorded in the fish head. Copper concentrations range from 1.50 to 5.43 mg/kg, and iron concentrations range from 67.25 to 90.58 mg/kg, with the greatest value found in fish heads. Nickel ranges from 5.78 to 13.90mg/kg and cadmium ranges from 1.38 to 3.68mg/kg; the fish head has the highest concentration of these elements. The region of the fish's head was discovered to have the highest concentration of all the heavy metals. This is due to the fact that the fish's gills are the first organs to be exposed to heavy metal exposure and are a significant site for heavy metal intake. However, when the levels of heavy metals in the fish from this Rivers was compared to the WHO's tolerable standard, the concentrations were significantly higher, raising serious concerns because, by all accounts, the Otammiri River is highly contaminated and these fish could have a negative impact on human health if consumed. Therefore, steps should be done to prevent additional River contamination.