Robert Ikechukwu Uroko; Obioma Uzoma Njoku
Abstract
This study evaluated the impact of heavy metal contents in vegetables grown in a palm oil mill effluents (POME) irrigated farmland on the biomes and well-being of humans that consume the vegetables. In this study, POME, a soil sample from POME irrigated farmland, and selected vegetables were evaluated. ...
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This study evaluated the impact of heavy metal contents in vegetables grown in a palm oil mill effluents (POME) irrigated farmland on the biomes and well-being of humans that consume the vegetables. In this study, POME, a soil sample from POME irrigated farmland, and selected vegetables were evaluated. The results showed high cadmium (Cd), chromium (Cr), lead (Pb), nickel (Ni),) and arsenic (As) and lower zinc (Zn) and copper (Cu) concentrations in POME relative to their respective permissible limits. The soil irrigated with POME had elevated levels of metals, comparable to the control soil, whereas vegetable growing in POME irrigated farmland contained increased amounts of most of the heavy metals above their respective permissible levels in edible vegetables. The plant concentration factors (PCF) of heavy metals detected in the vegetables were less than one except for V. amygdalina with PCF>1 for cobalt. The pollution load index of Cd, Cr, Cu, Co, and As in the POME soil were above 50, while high enrichment factors were obtained for Cd, Cr, Pd, Co, and arsenic. The geoaccumulation index indicated that the POME soil was strongly contaminated by Zn, Fe, Pb, Mn, Ni and extremely contaminated with Cd, Cr, Zn, Cu, and Co. The metals levels ingested daily from the vegetables were low, comparable totheir respective oral reference doses except for Mn in V. amygdalina and As in most of the vegetables. There was a high target hazard quotient for Mn, and As in most of the vegetables with hazard index (H.I.) >1 in each of the vegetables and increased cancer risk for Cd, Cr, Pb, Ni and As toxicity coupled with very high total cancer risks. These findingsshow that irrigation of farmlands with POME raises the heavy metal levels in vegetables and the risk of heavy metal toxicity.
Godfred Owusu-Boateng; Victoria Adjei
Volume 1, Issue 1 , March 2014, , Pages 28-34
Abstract
The problems of shortages and quality deterioration of water, have led to an increased interest in the reuse of treated grey water in many parts of the world. This study examined the suitability of locally available materials (beach sand, oyster shells, and charcoal) to treat grey water samples collected ...
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The problems of shortages and quality deterioration of water, have led to an increased interest in the reuse of treated grey water in many parts of the world. This study examined the suitability of locally available materials (beach sand, oyster shells, and charcoal) to treat grey water samples collected weekly from three halls of residence (Unity Hall, Africa Hall, and Independence Hall) on Kwame Nkrumah University of Science and Technology (KNUST) campus for irrigation. Beach sand, oyster shells, and charcoal were employed in the construction of three vertical flow-through filter systems, each consisting of PVC pipes of height 100 cm and internal diameter 5.08 cm. The grey water samples were filtered and the levels of physicochemical parameters (pH, conductivity, TDS and salinity), nutrient and microbial counts determined over a three-week period. Results indicate that the measured physico-chemical parameters treated grey water were within the permissible limits for irrigation water. Also filtration process is effective in reducing phosphate, the total and faecal coliform levels in grey water from the halls of residence. These observations suggest that treated grey water from KNUST campus would support production when used as irrigation water.
