Noor-ul Amin

Accumulation of heavy metals in edible parts of vegetables irrigated with waste water and their daily intake to adults and children, District Mardan, Pakistan

Green vegetable crops irrigated with wastewater are highly contaminated with heavy metals and are the main source of human exposure to the contaminants. In this study accumulation of eight heavy metals (Cu, Ni, Zn, Cr, Fe, Mn, Co and Pb) in green vegetables like Allium cepa, Allium sativum, Solanum lycopersicum and Solanum melongena, irrigated with wastewater in Mardan are studied using Atomic Absorption spectrophotometer. The studied metals in vegetable grown on wastewater irrigated soil were significantly higher than those of tube well water irrigated soil and WHO/FAO permissible limits (P<0.05). The most heavily contaminated vegetable was wastewater irrigated A. cepa, where the accumulation of Mn (28.05 mg kg(-1)) in the edible parts was 50-fold greater than A. cepa irrigated with tube well water irrigated soil. It may be concluded that both adults and children consuming these vegetables grown in wastewater irrigated soil ingest significant amount of these metals and thus can cause serious health problems.

Contamination of soil with heavy metals from industrial effluent and their translocation in green vegetables of Peshawar, Pakistan

Heavy metal pollution is a serious problem in countries like Pakistan, claiming soil, water and food resources rapidly due to negligence. Accumulation and bio-concentration of seven heavy metals in vegetables growing in a mixed industrial effluent irrigated agricultural field near Hayatabad, Peshawar, Pakistan were determined by atomic absorption spectrometry. Ranges of concentration of copper, cobalt, iron, lead, chromium, manganese, zinc and nickel were 0.044–0.504, 0.009–0.085, 0.243–7.737, 0.496–0.474, 0.005–0.033, 0.019–2.019, 0.045–0.703 and 0.017–0.108 ppm respectively, in the edible parts of different vegetables growing in the area. Iron (Fe) accumulated to the highest level in all vegetables (P < 0.05). In general root was heavily contaminated with the metals, showing significantly greater accumulation than in other parts (P < 0.05). A significant amount of the metals absorbed by the vegetables was translocated to the edible parts, indicating health concerns. Cultivation of vegetable crops with such industrial effluent is not recommended on the studied land without certain remediation.

Removal of Lead from Aqueous Solution by an Efficient Low Cost Biosorbent

Abstract Removal of Pb(II) ion from aqueous solution on modified sawdust obtained from Morus alba was investigated. The sample was characterized by BET surface area, EDX, FTIR and Zeta potential technique. The surface contains carbonyl and hydroxyl functional groups which act as binding sites for Pb(II) ion. Adsorption kinetics of Pb(II) on sawdust was tested by pseudo first order, Elovich and parabolic diffusion kinetic equations. The adsorption data were found to fit to Freundlich, Langmuir and Tempkin isotherms. The rate of adsorption was high at high temperature. Thermodynamic parameters like ΔH, ΔS and ΔG were calculated from the kinetic data. The positive values of ΔS reflect some structural exchange among the active site of the adsorbent and metal ion. The negative values of Gibbs free energy (ΔG) show the spontaneous nature of the process.

Removal of Heavy Metals from Aqueous Solution by Adsorption on Biomass Based Adsorbent

Abstract Removal of heavy metals i.e. Zn2+ and Cd2+ from aqueous solution by adsorption onto biomass based adsorbent was investigated as a function of time and different concentrations. The sample was characterized by FTIR, EDS, BET surface area and Zeta potential technique, which was reported earlier. Adsorption kinetics of Zn2+ and Cd2+ was tested by first order kinetics, Elovich and parabolic diffusion kinetic equations which show that the process of adsorption is diffusion controlled process. The rate of adsorption was high at high adsorption temperature. Thermodynamic parameters like ΔH°, ΔS° and ΔG° were calculated from the kinetic data. The negative value of Gibbs free energy (ΔG°) shows the spontaneous nature of the process. Freundlich, Langmuir, Temkin isotherms and distribution coefficient were found fit to the adsorption isotherm data.

Removal of Basic Red 5 on Calcined Kaolinite – Characterization and Adsorption Kinetics

Abstract Indigenous kaolin was collected from Swat district and then activated. The samples were characterized by BET surface area, FTIR, XRD, SEM, EDS, TGA/DTA, zeta potential and particle size analysis. Adsorption of basic red 5 on each sample was studied by adsorption kinetics at 20 °C, 30 °C and 40 °C. The residual concentration of the dye was determined by using UV–Vis spectrophotometer. The removal of basic red 5 from water solution was studied with respect to dye concentrations and equilibration time. Adsorption kinetics on kaolinite surface were analyzed by using parabolic diffusion, Elovich and Bangham models. Thermodynamic parameters like ΔE#, ΔH# and ΔS# were calculated from the adsorption kinetics data. The results show that the adsorption is a spontaneous and endothermic process. The negative value of entropy shows that the dye molecules take a proper position on the surface.