Pollution Characteristics And Risk Assessment Of Heavy Metal In Surrounding Soil And Plant Of A Smelter

As the rapid development of human society and industrialization especially happened in developing countries,increasingly amount of heavy metal is discharging into natural environment.More importantly,the accumulation of heavy metal in soil will not only affect the physi-chemical characteristics of soil but also it will go through the path of soil-plant-human to affect human health.What makes the situation worse is the transfer of heavy metal between soil and plant is a long term,hidden and irreversible process,once the heavy metals enter in human or other animals,they are hard to elimination.With the extended area and increasing amount,heavy metal pollution has become one of the most severe environmental problems for human beings.Thus,it is necessary to give some reference for heavy metal pollution governance and control.In this paper,through data collection and on-the-spot investigation,an area which in Jilin of a smelter was selected as research region.According to the soil and plant sampling in the area,total content and fractional content of heavy metals Ni,As,Cd,Pb in soils and plants were determined,which provides important data base and reference for the heavy metal pollution control.The conclusion is as follows:(1)To analysis soil heavy metal pollution in a smelter surrounding area.It indicated that the heavy metal content in soil was in an order of Ni > As > Pb > Cd.Among them,The maximum excessive points is Ni(up to 15),followed by As and Cd,Pb is not excessive.Through the single factor evaluation results,heavy metal Ni pollution of S06 sample in the surrounding soil is most serious(10.046 mg/kg).Most excessive point of nickel pollution belongs to the slightly polluted or mild pollution.S06 sample is slight contaminated with arsenic and cadmium.S04 sample point is high levels contaminated with cadmium.At the same time,the Pb content of all samples points are not excessive.(2)To analysis content of heavy metal of plant in a smelter surrounding area.By using of single factor analytic method to evaluate,the results show that fruit,stem,root of corn is inexistence heavy metal(Ni,As,Pb,Cd)pollution phenomenon.However,heavy metal content of root significantly higher than that of fruit and stem.Hence,it points out that it is of great importance for repairing soil heavy metal pollution to exclude roots and execute outside.(3)To research the enrichment regularity of heavy metals in corn.The distribution characteristic of heavy metals in corn: It indicated that the rate of heavy metals(nickel,arsenic,cadmium,lead)in corn was very low.What is more,it indicated that the accumulation ability of plants was in an order of root>stem>fruit.Combined with the actual results,it indicated that the fruits of the corn is safe.