بررسی میزان تجمع فلزات سنگین (سرب، کادمیوم، مس، نیکل و جیوه) در برخی از سبزی‌های کشت‌ شده در شهرستان‌های خرم آباد و الشتر استان لرستان در تابستان 1395

Background :Vegetables have a high capability in absorbing and storing heavy metals and the gathering of these materials in the human body causes unpleasant effects. The aim of the present study is the evaluation of the density and pollution caused by the elements cadmium , lead, mercury, copper, and nickel in leek, potato, and tomato in some farms in Khorramabad city. Materials and Methods: In one experimental study, after the sampling of farms and preparing samples, digestion and combination with HCL, the density of the elements cadmium , lead, mercury, copper and nickel were determined by means of atomic absorption apparatus in a graphite furnace. To statistically process  the findings, Spss software was used, and Excel software was used to present the findings. Finally, the results were compared with  WHO standards. Results: The results show that the average density  in heavy metals in various vegetables: levels of lead in leek (0.252), in tomato (0.304), and in potato (0.155) and the cadmium levels in leek (0.147), in tomato (0.216), in potato (0.081). The levels of nickel are as the follows: leek(47,98), in tomato (34,612), in potato (32,04). The levels of copper were as follows: in leek (0.149), in tomato (0.155), and in potato (0.148)ppm. Mercury was either absent or in trace amounts in the investigated vegetables. Conclusion: the reason for the high levels of lead  and cadmium compared with the permissible limit is probably due to too much phosphate fertilizers being used by farmers, the use of sewage slime, insecticides, fungicides, the using of too much animal residues and urban waste and also the closeness of agricultural fields to roads.