Physicochemical and Microbiological Qualities of Water and Soil Samples from Groundnut Oil Producing Industry

Abstract

Triplicate tap and wastewater samples collected from a groundnut oil producing industry in Akure metropolis, Southwest Nigeria were analysed for physicochemical and microbiological qualities using standard procedure. Adjoining soil samples were aseptically collected and serially diluted for total coliform counts using most probable number method. The range of the physicochemical qualities of the tap water and wastewater are as follows: pH (5.7-6.8), colour (4.98-90.0 HU), nitrite (1.6-20.0 mg/l), alkalinity (0.02-52.0 mg/l), BOD (1.79-2.87 mg/l) and TDS (1.59-33.0 mg/l); while for the soil samples, they are as follows: pH (6.7), alkalinity (32 mg/l), nitrate (9.98 mg/l), phosphate (15 mg/l) and total organic carbon (2.74 mg/l). Total coliforms ranged in the order of 104 to 105 cfu/ml and 104 to 105 cfu/g for tap water and soil samples respectively. The bacterial pathogens recovered from the water and soil samples include: Escherichia coli, Klebsiella spp., Pseudomonas spp., Bacillus spp., Proteus spp., Shigella spp., Enterobacter spp., Staphylococcus aureus, Streptococcus spp. and Salmonella spp., while the fungal isolates included Fusarium, spp., Aspergillus spp. and Penicillium spp. We conclude that the groundnut wastewater is important point sources of pollution in surface water with potential public health and ecological risks.