Assessment of Pollutants in Water and Sediment Samples in Lake Chad, Baga, North Eastern Nigeria

Abstract

The purpose of this research is to determine the levels of some physicochemical parameters in water and sediment sam-ples from Kwantan turare in Lake Chad, Baga, Borno State, Nigeria. Water samples were collected from five point des-ignated as S 1 to S 5 for the determination of biochemical oxygen demand (BOD), chemical oxygen demand (COD), dis-solved oxygen (DO) total dissolved solid (TDS), total suspended solid (TSS) anions and trace element. Sediment sam-ples were also collected for the determination of heavy metals and total organic carbon (TOC). These parameters were determined using approved standard procedures. The levels of heavy metals in the water and sediment samples were determined using atomic absorption spectrophotometer (AAS). The concentrations of DO, BOD, COD, TSS, TDS, TOC, nitrite, nitrate, Phosphate, Sulphate, and Chloride in the water samples from the five sampling point were higher than the WHO limits for the protection of fish and other aquatic life. The concentrations of Fe, Mn, Cu, Cd, Pb, Ni and Co in the water samples were higher than the WHO guideline limits, indicating severed pollution of this portion of Lake Chad. This high level of heavy metals in the water samples is expected owing to runoff of wastewater from agricultural activities within the study area. However, the concentrations of all the metals in the sediment samples were higher than the recommended values stipulated by WHO; indicating that the sediment samples from this portion of Lake Chad were also polluted by heavy metals. Results of Analysis of variance (ANOVA) revealed that the concentrations of all the pa-rameters studied were statistically significant among the sampling points. The prolonged presence of heavy metals in the water and sediment samples from this portion of Lake Chad give course for concern with time. The results of the study implies that continuous monitoring has to be carried out to ascertain the long-term impact of anthropogenic inputs to take remedial measures so as to ensure the health of aquatic life.