PHYSIOCHEMICAL

This study assessed the physicochemical parameters and heavy metals content in sediments from Orhiomwon River, Edo state, Nigeria. A total of nine (9) sediment samples were collected from the sampling stations from May, 2025 to July, 2025. Physicochemical parameters of sediments were analysed following standard laboratory procedures while selected heavy metals were determined following the method of the association of analytical chemistry. The average mean concentration of physicochemical and heavy metals parameters of sediments were 5.03±0.20 (pH), 43.67±10.44 (EC), 1212.61±165.52 (Ca), 287.33±93.92
(Mg), 297.91±81.39 (K), 161.62±32.71 (Na), 0.05±0.01 (N), 0.51±0.16 (TOC), 92.18±2.39 (sand), 5.94±2.38 (clay), 1.88±0.03 (silt), 2366.74±817.55 (Fe), 18.92±4.58 (Cu), 69.20±19.63 (Zn), 0.04±0.06 (Cd), 6.66±1.48 (Pb), 33.55±23.38 (Mn), 1.49±0.47 (Cr) and
27.24±10.41 (THC) respectively. Heavy metal concentrations followed the order: sand, silt and cadmium showed no significant differences (p > 0.05) across the three stations. On the other hand, pH, electrical conductivity (EC), calcium, magnesium, total organic carbon (TOC), clay, manganese, chromium, and total hydrocarbon content (THC) exhibited significant differences (p < 0.05) while potassium, nitrogen, sodium, iron, copper, zinc and lead showed a high significant difference (p<0.01) among the sediment samples from the different stations of Orhiomwon River. Fe>Zn>Pb>Cu>Mn>Cr>Cd. The results obtained in
this study showed that natural geochemical processes remained the dominant influence on Orhionmwon River sediments as signs of human activity especially from anthropogenic activities are evident.

Water is one of the elements and the necessity that most major global to the daily life. The physico-chemical properties of the upstream, midstream and downstream of Udu River in Delta State, Nigeria were investigated in this work. The properties
were compared to the World Health Organization (WHO). The physico-chemical properties considered and their average values are pH (7.06 ± 1.01), temperature (31.33 ± 0.58℃), turbidity (10.22±1.10 NTU), alkalinity (8.77±0.68 mg/L), electrical conductivity (140.03±62.50 𝜇S/cm), dissolved oxygen (2.67±0.25 mg/L), biochemical oxygen demand (1.65±0.35 mg/L), total dissolved solids (79.82±35.61 mg/L), total suspended solids (0.87±0.56 mg/L), nitrate (5.19±0.51 mg/L), chloride (6.67±2.96mg/L), bicarbonate (2.51±0.27 mg/L), sulphate (1.13±0.32 mg/L), chemical oxygen demand (16.00±5.29 mg/L), phosphate (8.06±4.34 mg/L), total hardness (15.61±2.13 mg/L), iron (0.77±0.12 mg/L), zinc (0.01±0.01 mg/L), Chromium (0.18±0.07 mg/L), manganese (0.07±0.06 mg/L), copper (0.03±0.00), sodium (0.70±0.00 mg/L) and potassium (0.82±0.00 mg/L). The values of the
physico-chemical properties in comparison with the WHO standards of portable water indicate that Udu River needs to be constantly monitored in order to preserve its quality for safe consumption.