Hydro-chemical and microbial assessments of water resources around cassava mills in a sedimentary formation of Ilaro, Southwest Nigeria

Abstract

AbstractThe use of water resources from hand-dug wells, boreholes and streams around cassava processing mills within Ilaro metropolis, Ogun State Nigeria for domestic and industrial activities had led to the assessments of water resources in the vicinities of Ekueme, Olorungbogo, Double Crown, Olalandu and Akewe cassava mills. Eleven water samples were collected and taken to the laboratories for physiochemical, heavy metals and microbial analyses. The values obtained were compared with the WHO standards for drinking water. The pH (4.68–7.41) revealed acidic water with relatively low temperatures (24.7–29.2 ℃). The EC (79.80–221.00 mS/cm) indicated very high level of dissolved ionic salts, TU (0.200–0.684 mg/L) revealed the presence of particulate matters, and TH (15.10–22.70 mg/L) showed moderate water hardness. The anions NO3−, PO43− and Cl− concentrations indicated contaminations ranging from 65.42–110.80, 7.210–8.310 and 195.25–427.00 mg/L, respectively. Cations Na+, Ca2+ and Mg2+ had relatively low concentrations ranging from 14.49–20.96, 4.30–11.29 and 10.50–11.50 mg/L, respectively. The concentrations of Fe, Ni, Cd and Pb were high and ranged from 3.87–5.10, 1.27–2.82, 0.07–2.69 and 0.03–0.96 mg/L, respectively. The microbial counts in for total bacteria, fungi, E. coli and total coliform were also high ranging from 1.0–93.0, 0.1–1.3, 0.1–9.2 and 0.1–9.3 (106 CFU/ml), respectively. All these parameters indicated statistically significant difference between their concentrations at p = 0.000 and between the physiochemical and microbial results at p = 0.006. The qualities of the water resources around the study areas had been highly compromised and are not suitable for domestic activities.