Health Risks of Potentially Toxic Metals (PTMs) in Soil and Water of Agbara Industrial Estate

Abstract

The presence of potentially toxic metals (PTMs) in soil and water is of great concern to the public health, agriculture and environmental health because of their toxicity. This study was carried out to examine the concentration of ten PTMs (Mn, Fe, Zn, Ni, Se, Cd, Co, Cr, Cu, Pb) in soil and water within Agbara Industrial Estate. The samples were analysed for PTMs concentration using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The analysis revealed that the mean concentration of the analysed PTMs in water vary in the following order: Fe > Zn > Se > Mn > Pb > Ni > Cr > Co > Cu > Cd. The concentration of Mn, Cu, Ni, Se, Co, Pb and Cr in water samples were above the WHO set limit while the concentration of Fe, Zn and Cd were below the set limit. The concentration of the heavy metals in soil ranges from 6.097 to 40.676 mg/kg for Mn, 242.91 to 317.87 for Fe, 0.272 to 1.014 for Cu, 0.337 to 30.551 for Zn, 0.060 to 0.289 for Ni, 0.257 to 0.989 for Se, 0.098 to 0.341 for Co, 0.074 to 15.644 for Pb, 0.105 to 0.378 for Cd to 13.74mg/kg. The estimated daily intake (EDI) peaked at 5.1 x 10^-8 and 2.5 for Fe in soil and water samples respectively, and minimum of 1.2 x 10^-11 (Ni) and 0.003 (Pb) in soil and water samples respectively. The EDI from the soil samples falls at extremely low risk level and are therefore within acceptable range. The EDI for water samples however is at the extremely high-risk level, implying quick solution to avoid any health hazards. The minimum carcinogenic risk of 0.0099 was observed for Cd in the water samples and 1.9 x 10^-12 for Ni in soil samples, with the maximum risk of 10.4 and 10 x 10^-9 recorded for Fe in water and soil samples respectively. The carcinogenic risk from the soil samples is at extremely low risk level and are therefore within acceptable range. The mean carcinogenic risk from water samples for Mn, Fe, Cu, Zn, Ni, Se, Co and Cr falls within the high-risk level which requires immediate attention for proper action. The carcinogenic risk from water samples for Cd and Pb are within the extremely high-risk level which implied that fast action be taken to avoid health hazards. The study revealed that water from the Agbara Industrial Estate is associated with potential health risk and may not be suitable for consumption which calls for immediate attention and thereby recommend prompt sensitization of the people within this study area on the hazard level.