Assessment of Potential Ecological Risk of Heavy Metals in Soils from Waste Dumpsites in Military Formations in Makurdi, Nigeria

Abstract

Chemical fractionation of toxic metals (As, Cd and Zn) along the soil profile at waste dumpsites in military formations for dry and wet seasons using Tessier's sequential extraction procedure was determined using AAS techniques. The order of yield across the fractions was mainly: exchangeable (F 1 ) < carbonate-bound (F 2 ) < Fe/Mn oxide-bound (F 3 ) < organic matter-bound (F 4 ) < residual (F 5 ). Statistical analysis (p < 0.05) indicated that there was no significant variation between the values of results obtained from dumpsites A and B of each sampling station. However, the variation between the dumpsites and control was significant (p > 0.05) in most stations. The pollution index was assessed using the degree of contamination (C d ), the modified degree of contamination (mC d ), potential ecological risk and mobility factor. The C d indicated that NFB top soil was considerably contaminated (16.3) while the soils (20 -40 and 40 -80 cm) recorded moderate (13.6) and low (5.60) contaminations respectively. Top soil of NSM was moderately contaminated while the contamination status of NPS, NFB and SFB waste dump soils across the depths was "low". The mC d index for NFB dump soil was "moderate" (2.33) and subsoils (20 -40 and 40 -80 cm) were "low" (1.94) and "Nil to very low" (0.800) respectively. The mC d for the other three dumpsites was "Nil to very low" except the top soil of NSM which was "low". The order of the toxic metals mobility in the studied soils using the Mobility factor (M f ) for dry and wet seasons was Cd > As > Zn and Zn > Cd > As respectively.

Impact of Seasonal Variations and Oil Activities on the Total Concentrations, Geochemical Fractions, And Human Health Problems of Trace Metals in Soils Within the Oil-Bearing Communities of South-South Region of Nigeria

“…Consequently; higher mean RI values were obtained in the dry than in the rainy season. The higher mean RI values in the dry season reported agree with the results obtained by Nwankwo et al (2019). This could be credited to the dilution and leaching of metal concentrations in soil during the rainy season and the concentration of metal concentrations by evaporation in the dry season.…”

“…This could be credited to the common source of metal contaminants (oil and oil-related activities) at all the studied communities (Ayenimo et al, 2005;Lu et al, 2010). However, the mean values of Cdeg of the different studied locations during the dry and wet seasons demonstrated some variations as reported by Nwankwo et al (2019). This could be credited to the disparity in the atmospheric deposition, runoff, and soil properties among the different sites investigated between the dry and wet seasons (Gunawardena et al, 2013;Biswas et al 2018;Gunes, 2022).…”

Level of Heavy Metals and Potential Ecological Risks in Irrigated Horticultural Farms in the Vicinity of Lake Ziway, Central Ethiopian Rift Valley Region

“…CF is an index applied to assess the pollution level of a single heavy metal and shows site-specific soil contamination by the targeted heavy metal. CF is calculated using the following equation [ 17 , 18 ]: where C s = the mean metal concentration of the specific metal at the sampling site and C r = concentration of a given element in the reference/baseline or background. There were no data on the heavy metal concentrations at the study site or the national level in Ethiopia.…”

“…CF is an index applied to assess the pollution level of a single heavy metal and shows site-specifc soil contamination by the targeted heavy metal. CF is calculated using the following equation [17,18]:…”

Effects of Bio-Slurry and Chemical Fertilizer Application on Soil Properties and Food Safety of Tomato (Solanum lycopersicum Mill.)

“…Te CF was used to express the level of contamination of soil by heavy metals [36]. Tis method has been developed further in soil analysis [37,38]. It was calculated as a ratio between the measured concentration of the heavy metal in soil and the preindustrial reference value of the same metal as follows:…”