Distribution of Heavy Metals in Fish Organs,water and Sediments from Ureje Reservoir

Heavy metal contamination in aquatic ecosystems has become a significant environmental and public health concern due to increasing industrial, agricultural, and urban activities. Hence,this study investigated the distribution of heavy metals in fish organs, water, and sediments from Ureje Reservoir, Ado-Ekiti, Nigeria. The samples were collected, digested and analyzed using Atomic Absorption Spectrophotometry. Also, fish species were identified as Oreochromis niloticus, Sarotherodon melanotheron and Oreochromis aureus. The biometric measurements of the fish was measured and the condition factor (K) for Oreochromis niloticus, Sarotherodon melanotheron and Oreochromis aureus ranged from (1.8-2.2 , 1.8-1.9 and 1.9 respectively). The results revealed varying concentrations of arsenic, cadmium, chromium, iron, and lead. Fish gills exhibited the highest accumulation of heavy metals (1.24 ppm), reinforcing the impact of direct waterborne exposure, followed by the muscles (0.83 ppm) and liver (0.80 ppm), while sediment samples contained the highest concentrations of iron (84.39 ppm). Heavy metal levels in fish remained within the WHO permissible limits, bioaccumulation over time could pose a significant threat to aquatic organisms and humans who consume fish from the reservoir. Water samples exceeded WHO permissible limits for Cr and Pb (0.05 ppm and 0.01 ppm, respectively), raising concerns about bioaccumulation and human exposure risks. Sediment analysis also confirmed the presence of heavy metals, suggesting long term environmental contamination from external sources. The heavy metal concentration in the samples were in the order gill>sediment>liver>water>muscle. The findings suggest that continuous pollution from anthropogenic sources is affecting water quality and aquatic life. The presence of toxic metals in fish tissues raises potential health hazards for consumers, necessitating urgent intervention. This study highlights the need for stringent pollution control measures, regular environmental monitoring, and public awareness to mitigate the impact of heavy metal contamination. Proper waste management and water treatment strategies should be implemented to ensure the safety of aquatic life and human populations dependent on the reservoir.