Assessment of Selected Heavy Metals in Water, Sediments and Fish Species in Twin Lake, Unizik Golf Course, Awka, Anambra State, Nigeria

Abstract

This study assessed some heavy metals in water, sediments and fish species from Twin Lake, UNIZIK Golf Course, Awka, Anambra State, Nigeria. Three samples each of water, sediment and fish were collected at three different locations in each lake (Lake 1 and 2) for analysis of some selected heavy metals: Zinc (Zn) Mercury, (Hg), Arsenic (As), Cadmium (Cd) and Lead (Pb) to determine the extent of pollution in these lakes. Samples were collected in June, July and August 2024. The heavy metals were determined by atomic absorption spectrophotometry (AAS). The results revealed that the heavy metal concentrations in water were found to be in the order: Zn>Cd>Pb>Hg>As. The highest concentration (0.76 ±0.00ppm) was obtained in Zn in the month of June in Lake 1 and lowest (0.00±0.03ppm) in As in the month of June in Lake 1. In the sediments, the heavy metal concentrations were found to be in the order: Zn>Cd>Pb>Hg>As, the highest concentration (5.72 ±0.51ppm) of heavy metal in the sediment was obtained in Zn in the month of August in Lake 2 and lowest (0.01±0.00ppm) in As in the month of June in Lake 1. While in the fish species (Oreochromis niloticus), the heavy metal concentrations were found to be in the order, Zn>Cd>Pb>Hg>As, the highest concentration (8.94 ±1.08ppm) of heavy metal in fish samples was obtained in Zn in the month of June in Lake 2 and lowest (0.01±0.00ppm) in As in all the sampling months in both lakes. However, the heavy metal concentrations were found to be higher in Lake 2 compared to Lake 1. All the heavy metals levels determined were below the maximum permissible limits set by FAO/WHO in both lakes. The water quality parameters indicate that the Twin lakes are suitable for aquatic life. It is therefore recommended that there should be continuous surveillance and monitoring of the pollution levels of the lakes to provide adequate information necessary for its effective management and conservation of the aquatic resources Moreover, practices that increase the heavy metal load such as indiscriminate dumping of refuse, agricultural fertilizer effluents as well as laundry and bathing activities along the lake course should be discouraged.