Determination of heavy metals concentration in soils and selected vegetables and their potential human health risks / Nawal Izzati Aminudin

Vegetables are essential for human diet due to their nutritional contents and often associated with toxic metals that derived from contaminated land where the vegetables are grown. This study was conducted to assess the concentration of heavy metals namely Cd, Cu, Pb and Zn in soils and selected vegetables and their potential human health risks. The preparation of samples were conducted by using wet digestion method before analysis using Atomic Absorption Spectrometer (AAS) to determine the concentration of selected heavy metals. The heavy metals concentration in the soils were ranged from 4.15 to 18.25 mg/kg, 11.10 to 13.00 mg/kg , 60.50 to 137.90 mg/kg for Cu, Pb and Zn respectively. The heavy metals contained in edible parts of the cucumber, mustard green and sweet potato were approximately in the range of 2.20 to 4.78 mg/kg, 3.25 to 7.70 mg/kg and 58.85 to 95.85 mg/kg for Cu, Pb and Zn respectively. Cd was not detectable in all soils and vegetables samples. Analysis of Variance (ANOVA) was conducted to compare heavy metals concentration in selected vegetables and p- value < 0.05 obtained indicating statistically significant different. The health risk assessment was conducted by using Target Hazard Quotient (THQ) formula and Hazard Index (HI). The results obtained were higher than 1 indicating adverse health effect on the population. The concentration of Pb in soils and vegetables samples were higher than permissible-maximum limit regulated by FAO/WHO. Thus, same lead contamination found in soils and all edible part of the vegetables from Selangor Fruits Valley.