Seasonal and Spatial Variability of Nitrate Concentration in Aquifers of Makurdi Metropolis and Its Environs, North Central Nigeria (Published)
This study examined seasonal and spatial variation of nitrate concentrations in aquifers of Makurdi metropolis and environs, with implications for drinking water quality. Twenty-five boreholes were purposively selected to represent major settlements and aquifer types, and samples were collected in the wet (September 2024) and dry (April 2025) seasons using the grab method. Coordinates at each sampling point were recorded with GPS, potential pollution sources documented, and samples analysed for nitrate using spectrometric method in line with APHA (2017) and WHO standards. Spatial variability was mapped with ArcGIS 10.8.2 using Inverse Distance Weighted (IDW) interpolation. Results showed seasonal variation, with mean nitrate levels of 24.26 mg/L in the wet season and 22.27 mg/L in the dry season. While most boreholes complied with the Nigerian Standard for Drinking Water Quality (50 mg/L), exceedances were observed in BH5 (54.4 mg/L) and BH11 (52.1 mg/L) constituting 8% during the wet season, and in BH11 (51.1 mg/L) constituting 4% during the dry season. Elevated concentrations clustered in urban and peri-urban zones such as Akpehe, BSU, Logo, and Agan, largely due to agriculture, sanitation lapses, and waste disposal, whereas deeper aquifers (>100 m) generally showed lower levels. The findings highlight localised nitrate risks, underscoring the need for groundwater protection, improved sanitation, controlled fertilizer use, and safe alternative water sources.
Keywords: Groundwater, Seasonal variation, Water Quality, aquifers, nitrate, spatiatil variation
Determination of Phytochemical Properties of Moringa Oleifera Seed Powder as Bio-Coagulant in Wastewater and Groundwater Treatment (Published)
This study was design to assess Moringa oleifera, seed powder as bio-coagulant in wastewater and groundwater treatment. Fresh, healthy and matured seeds of Moringa oleifera, were bought from Ekeonunwa market Owerri and processed into fine powders. Qualitative phytochemicals screening of aqueous extracts of the seed powders were carried out. Physicochemical parameters such as colour, odour, appearance was checked using ten (10) different observers while pH, turbidity, electrical conductivity (EC), total dissolved solids (TDS), biological oxygen demand (BOD), dissolved oxygen (DO) and chloride (Cl-) were assessed according to standard technique. The result revealed the presence of phytochemicals; alkaloids, flavonoid, phenols, tannins, steroids, saponins, and anthraquinonesin M. oleifera, the treatment of groundwater indicates a change in colour, odour, appearance, and pH, which compare favorably with the control while temperature, EC, TDS, DO, BOD and Cl- were statistically the same before and after treatment,while the turbidity increases across the different treatment.
Keywords: Groundwater, Moringa oleifera, Treatment., bio-coagulant, powder, wastewater
Heavy Metal Contamination and Health Risk Assessment of Groundwater Sources to Waste Dumpsites in Port Harcourt (Published)
Heavy metal contamination and health risk assessment of groundwater ingestion in proximal relation to waste dumpsites in Port Harcourt were investigated during the rainy and dry season of 2020. Five (5) sampling points were established and designated as Groundwater (GW) as follows: GW1, GW2, GW3, GW4, and GW5 respectively. The control station used was GW5. Nine (9) heavy metals (Cd, As, Mn, Cu, Hg, Ni, Fe, Pb, and Zn) were assessed during the period using an atomic absorption spectrometer and were compared with National Standard for Drinking Water Quality (NSDWQ) of Nigeria. The Estimated Daily Intakes of Metal (EDIM) of these metals for adult males, females, and children revealed no significant health issues during the wet and dry seasons. However, the Health Risk Index (HRI) for non-carcinogenic revealed that during the wet season Pb in the control station (GW5) had a concentration of 4.000E+0 mg/kg/day that was far higher than unity (HRI<1) for females. The Arsenic (As) values for children at GW1, 2, and 3 were also higher than unity. The pollution index for each heavy metal across sample location showed that Fe in GW1 and 3 during the dry season was high while in the wet season, values for Cu in GW4 was very high, Fe in GW1 and 2, and Mn in GW2 were higher than the unity. The overall pollution index of the heavy metal studied revealed that only Fe exceeded the unity value during the dry season whereas Cu, Fe, Pb, and Mn concentrations were also higher during the wet season. This calls for concern considering the vulnerability of children and women who may have been exposed to groundwater sources via ingestion. The heavy metal contamination as observed in this study may have occurred due to anthropogenic activities superimposed by the unregulated insanitary waste disposal phenomenon.
Citation: Alaye A.S. Bibiye; David N. Ogbonna; Sodienye A. Abere; Augusta Ayotamuno (2022) Heavy Metal Contamination and Health Risk Assessment of Groundwater Sources to Waste Dumpsites in Port Harcourt, International Journal of Environment and Pollution Research, Vol.10, No.2 pp.34-49
Keywords: Groundwater, Heavy Metal, Pollution Index, Waste Management, health risk assessment.