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This study examines toxic metal concentration and bacteriological characteristics of effluents in some parts of southwestern Nigeria. Fourteen wastewaters were analyzed for their trace metal content using Inductive coupled plasma optical emission spectrometry (ICP-OES) while 72-samples were examined for the presence of bacterial load using Standard Microbiological methods (THC-Total viable count and TCC-Total coliform count). Isolates identities were confirmed with relevant biochemical tests. Elevated concentrations of Cu-0.299µg/l, Pb-0.10µg/l, Zn-4.62µg/l, Cr-0.20µg/l, As-0.3µg/l, Ni-0.192µg/l, Cd-0.02µg/l, Se-0.02µg/l, Co-0.099µg/l, V-1.71µg/l, U-0.50µg/l, Sr-1.81µg/l and Ba-0.82µg/l were observed in the cassava market/industry wastewater: signifying this as the most contaminated water in the area. Fe-24.8mg/l in the school wastewater may be geogenically sourced; indicating high degree of weathering with the presence of ferromagnesian minerals while Cu and As in cassava waste-water might be compositional based through bioavailability uptake/sources. Bacteriological analysis revealed Enterobacter spp. and Escherichia coli across all sampled sites; these were consistently present in the wastewaters and are primarily considered as indicators of faecal pollution capable of affecting human health via contamination of surrounding drinking water sources. These species have been associated with several clinical conditions such as pus formation, pneumonia, rheumatic fever and infections in immune compromised inhabitants while others cause severe illness such as respiratory and urinary tract infections in humans. Concentration of toxic metals in the cassava market/industry wastewater should be controlled or monitored and the wastewater made less toxic by constant treatment with adequate remediation facilities to remove the toxic constituents before discharging them to surface water bodies. [ABSTRACT FROM AUTHOR]

Geophagy clay has been used in tropical regions as gastrointestinal protector for adsorbing toxins in human body, but it was rarely used in adsorbing heavy metals contaminants in water. This study determines elemental concentration of geophagy clay and evaluates its adsorptive capacity in removing Cd2+ and Pb2+ in water. Fifteen clay samples were randomly collected from three layers in the space of one meter apart from Amawom clay deposit in Ikwuano local government, Southeast Nigeria. Elemental analysis was carried out using the inductively coupled plasma mass spectrophotometer (ICP-MS), and chemical characterization was performed with Fourier transform infrared spectroscopy (FT-IR) and X-ray diffractometer (XRD). The adsorptive capacity of Cd2+ and Pb2+ on the clay samples was evaluated using standard solutions of the metal ions. The result of the elemental analysis in mg/kg (Pb ≤ 12.4, Zn ≤ 2.75, Co ≤ 1.50, Ni ≤ 1.47, Mn ≤ 15.0, Cd = 0.01, Ca ≤ 300, Al ≤ 3466, Na ≤ 13.3, and Hg = 0.02; P ≤ 40.0) revealed that the concentrations of most of the studied metals in the three layers are statistically similar and fall below the permissible recommended safety levels. The presence of functional groups (hydroxyl, amine, and carboxylic/ester) and minerals (kaolinite, goethite, and quartz) provided evidence of the good adsorptive properties of the clay samples. The adsorption of Cd2+ and Pb2+ unto the clay samples increased with increase in pH, concentration, time, and temperature, and the equilibrium data for the adsorption fitted well into Langmuir isotherm. The study, therefore, concluded that geophagy clay possesses the capacity to adsorb Cd2+ and Pb2+ for water treatment. [ABSTRACT FROM AUTHOR]

Efforts to monitor groundwater qualities in conjunction with its interaction with rocks and minerals are still in continuous process. The role of joints and fractures in the natural filtration process which aid the enhancement of underground water quality need to be examined. Therefore, the sub-surface structures together with the anisotropic properties of fractures and direction of underground water flow in the bedrock of four (4) emerging communities within Ibadan metropolis was investigated. One hundred and fifty seven (157) groundwater samples were collected, analyzed geochemically using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) while square array method was adopted for investigating the structures. The pH values in the study area vary from 6.65-7.90 suggesting near neutral to alkaline nature of the water. The electrical conductivity (EC) vary from 107 μscm-1 to 551 μscm-1 this falls between the permissible level of World Health Organization. Higher carbonates-432 mgl-1 values than the WHO-340 mgl-1 standard indicate water hardness derived from carbonates mineral in the migmatite/gneissic rock. Total hardness a common property in Ibadan waters signifies water that is hard in terms of soap consumption and harsh in taste. The highest observed concentration for the TH is 563 mgl- 1 which is above desirable limit (119 mgl-1) of WHO-2004 for total hardness. Fractures orientation correlated adequately with the measurements of joints and fractures obtained during mapping exercise. These directions might have a connection to the direction of underground water flow it may also increase the vulnerability influence of the water to CO32- and hardness. In conclusion, a reasonable hygienic culture and cleaning management should be imbibed in order to ensure safer water devoid of leachates that can be conducted through fractures into groundwater systems. [ABSTRACT FROM AUTHOR]

The pollution of river water and sediments by heavy metals has assumed serious problems due to their toxicity and accumulative behaviour globally and locally. This research paper aim at mapping heavy metal contamination in urban rivers in Ibadan metropolis, Nigeria namely; Ona and Omin using GIS techniques. Systematic method of sampling stream sediments along the drainage channels was adopted. In all, fifty-eight (58) samples were collected and analyzed for heavy metals such as As, Cd, Cu, Pb, Zn etc using inductively coupled plasma-optical emission spectrometry (ICP-OES) at ACME in Canada. The concentration of the heavy metals was compared with water quality standard prescribed by WHO, BIS, ICMR, FAO, SQG-TEC and PEC. Geochemical maps of heavy metal distributions were produced using Arc GIS 10. However, general assessment shows that Ona and Omin rivers are polluted. It is therefore recommended that urgent management steps be taken to arrest future deleterious effects and sustainability of these water bodies for human consumption. [ABSTRACT FROM AUTHOR]

A combined geological and geophysical evaluation was made of the groundwater potential of the Ajana, Remo North area in south-western Nigeria: the geology and other structural features of the rocks there strongly influenced and correlated the aquifers' storability and transmissivity. Geological mapping revealed that the area was made up of granite, quartzite and varieties of gneiss, some of which have good secondary porosity and permeability. Ten vertical electric soundings (VES) stations were established using a Schlumberger electrode array. Five geoelectric layers consisting of topsoil, sand, clayey-sandy, fractured/weathered basement and flesh bedrock were delineated. The aquifer layers were the 38.3m thick 283 ?m resistivity sand/sandy clay and 55-518 ?m resistivity fractured/weathered basement. Other geoelectric parameters used in evaluating the area's hydrogeological potential included curve type, anisotropy coefficient and reflection coefficient -- The QH curve type was predominant in the area. The anisotropy Coefficients suggested VES stations having high groundwatcr potential ranging from 1.4 -- 1.56; while the reflection coefficients for the area ranged from 0.21 -- 0.99. The overall results showed that VES stations 8, 9 and 10 could be possible groundwater sources having high expected yield. [ABSTRACT FROM AUTHOR]

Geophagy clay has been used in tropical regions as gastrointestinal protector for adsorbing toxins in human body, but it was rarely used in adsorbing heavy metals contaminants in water. This study determines elemental concentration of geophagy clay and evaluates its adsorptive capacity in removing Cd 2+ and Pb 2+ in water. Fifteen clay samples were randomly collected from three layers in the space of one meter apart from Amawom clay deposit in Ikwuano local government, Southeast Nigeria. Elemental analysis was carried out using the inductively coupled plasma mass spectrophotometer (ICP-MS), and chemical characterization was performed with Fourier transform infrared spectroscopy (FT-IR) and X-ray diffractometer (XRD). The adsorptive capacity of Cd 2+ and Pb 2+ on the clay samples was evaluated using standard solutions of the metal ions. The result of the elemental analysis in mg/kg (Pb ≤ 12.4, Zn ≤ 2.75, Co ≤ 1.50, Ni ≤ 1.47, Mn ≤ 15.0, Cd = 0.01, Ca ≤ 300, Al ≤ 3466, Na ≤ 13.3, and Hg = 0.02; P ≤ 40.0) revealed that the concentrations of most of the studied metals in the three layers are statistically similar and fall below the permissible recommended safety levels. The presence of functional groups (hydroxyl, amine, and carboxylic/ester) and minerals (kaolinite, goethite, and quartz) provided evidence of the good adsorptive properties of the clay samples. The adsorption of Cd 2+ and Pb 2+ unto the clay samples increased with increase in pH, concentration, time, and temperature, and the equilibrium data for the adsorption fitted well into Langmuir isotherm. The study, therefore, concluded that geophagy clay possesses the capacity to adsorb Cd 2+ and Pb 2+ for water treatment., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 T. M. Osobamiro et al.)