Study On The Pollution Character Of Heavy Metals On Wheat From Mining Area In North Of Xuzhou

Heavy metals produced by coal mine production and using process can make the nearby farmland soil polluted, and through bioaccumulation pollute the crop.However,the heavy metal content in the soil is not the only reason for heavy metal pollution of crops,many research results show that plants absorb from the atmosphere is one of the reasons for the pollution of heavy metal in crops. Therefore, to identify the sources of heavy metals pollution in Beijiao area of wheat in Xuzhou, has the vital significance to the treatment of heavy metals pollution in mining area and food security management.This paper through the determination of heavy metals in mature wheat root, stem and leaf, glume, seeds from the study area, evaluation of food safety and human health risk; combined with the results of correlation analysis, the experiment of wheat seedlings response to different environmental factors and investigation of pollution sources, to explore the source of heavy metals pollution of wheat. Finally come to the following conclusions:(1)Compared with China’s agricultural industry standards and China’s food hygiene standards,within the study area 24 sampling points of wheat seeds in the four heavy metals Pb,Cd, As, Cr were exceed the standard1.65 times, 0.10 times, 0.60 times, 1.51 times respectively, while the Cu, Zn two kinds of heavy metals did not exceed the standard.Spatial distribution characteristics of heavy metals show that heavy metal content exceed the standard is closely associated with coal mine industry distribution.(2) Heavy metals in wheat seeds of study area is characterized by single factor pollution index: Pb>Cr>As>Cd>Cu>Zn. The order of heavy metals through oral intake pathway to human health risk caused by As>Pb>Cu>Cd>Zn>Cr. The size of the content of Zn, Cu in different organs of wheat mature stage by the order: root>seed>leaf>glume size; the size of content of Cd, Pb, As in different organs of wheat mature stage by the order: root>glume>leaf>seeds; and the size of the content of Cr in different organs of wheat mature stage by the order:glume>leaf >root>seeds.Within the study area of heavy metal content in the root of wheat proportion is low,that is not consistent with the general research results of crops affected by soil pollution, may be influenced by the regional air pollution.(3) There is a remarkable correlation between Pb, Cd, Cr, As of wheat seeds; there is a remarkable correlation between Cr of wheat seeds and Cr in root,glume; while there was no significant correlation between Pb, Cd, As and the content of heavy metals in soil and other organs. There is a remarkable correlation between the content of Cu of wheat seeds and Cu of soil, root, stem and leaf, glume; there is a remarkable correlation between the Zn of wheat seeds and Zn in root, stem and leaf, glume.(4) The wheat seedling planting experiment was carried out in the mining area and mine campus,the results show that, compared with the samples of wheat seedlings planting in campus, there is a significantly decrease with the content of six heavy metals after Na2-EDTA treatment which planting in Beijiao; compared with the samples of wheat seedling in Campus, the wheat seedling which planting in Beijiao, root tip cells within the nucleus much bubble serious and disorder; leaf blade cell within chloroplast swelling and the structure is messy.Further explained the atmospheric environment pollution has relation to the wheat pollution.