Heavy metal determination of unfertilised vegetables and univariate analysis of the results

Heavy metal contamination in water and food samples is thought as the result of human activities such as agriculture, traffic and industrial process in this century. Trace metal contents in the soil have increased with the contributions of both industrial and agricultural operations. Chemical fertilizers cause unbalance of the food in the soil. When these facts considered heavy metal accumulation in the vegetables may be occurred because of the over fertilization. In recent years interest on vegetables that fertilization is not applied has increased. In this study some heavy metal contents such as Cu, Fe, Mn, Ni and Zn have determined via ICP-OES by using microwave solubilisation system in vegetable samples from four different regions on which greenhouse and chemical fertilization process is not applied. The validity of the method is controlled with certified reference material (Tomato Leaves (NIST1573a). Recovery values have found over 95 %. Univariate ANOVA test is applied on experimental results. Since Sig. value is p>0.05 and F<F k for each vegetable samples, it is seen that group variants are homogenous and there is not a significant difference between the soils of the four region.