Characteristics And Risk Assessment Of Heavy Metal Pollution Of Soil In Crops

Soil-crop heavy metal pollution has been widely concerned,especially in the mining area soil-crop heavy metals will pollute the surrounding environment,and have a serious impact on human health,has become the focus of attention of scholars at home and abroad.In order to find out whether there is heavy metal pollution and health risk in the surrounding area of coal mine in Henan Province,this paper takes three cities of CJ(Che Ji),XZ(Xin Zhuang),CSL(Chen Si Lou)and Yuzhou City,The pollution index method and the potential ecological hazard index method were used to evaluate the results of the three coal mining areas in the three coal mining areas of XY(Da Tan Gou)and FS(Jing Shi)(Zn,Cd,Pb,Tl)in six coal mining areas of Yongcheng City and Yuzhou City,and the effects of heavy metals(Cr,As,Ni,Cu,Zn,Cd,Pb,Tl)Of the heavy metal content,so as to Yongcheng and Yuzhou coal mining area of wheat and corn for crop risk assessment.The results are as follows:(1)CJ,XZ,CSL,QS,XY,FS 6 coal mine soil pH> 7,are presented as alkaline.Compared with the secondary standard of soil environmental quality standard(GB15618-2008),the contents of heavy metals in soil of CJ coal mine area are in addition to Zn and Cd content,and the other five heavy metals Cr,As,Ni,Cu and Pb are not exceeded.The contents of Cr,As,Ni,Cu,Zn,Cd and Pb in seven soils of XZ coal mine are not exceeded.The Cr,Co,Ni,Zn,Cd and Pb of the other six kinds of heavy metal elements in the CSL coal mine area were not exceeded.The heavy metal elements Cr,As,Ni,Cu,Zn,Cd and Pb in 7 soils of QS coal mine have not exceeded the standard.The contents of heavy metals Cr,As,Ni,Cu,Zn,Cd and Pb in seven soils of XY coal mine are not exceeded.The contents of Cr,As,Ni,Cu,Cd and Pb in the other six kinds of heavy metal elements were not exceeded.(2)The contents of Cr,As,Ni,Cu,Zn,Cd,Pb and Tl in the soil of CJ coal mine were different in different degrees,and the contents of heavy metal in soil of Henan Province were evaluated.The contents of Cr,As,Ni,Cu,Zn,Cd,Pb and Tl in the soil of XZ coal mine have different degrees.The contents of Cr,As,Ni,Cu,Zn,Cd,Pb and Tl in the soil of the CSL coal mine are different in different degrees.The contents of heavy metals Cr,As,Ni,Cu,Cd,Pb and Tl in the soil of the QS coal mine are not exceeding the standard.The contents of Cr,As,Ni,Cu,Zn,Cd,Pb and Tl in the soil of XY coal mine are different in different degrees.The contents of Cr,As,Ni,Cu,Zn,Cd,Pb and Tl in the soil of FS coal mine are different in different degrees.(3)By comparing the degree of heavy metal pollution in soils of different coal mining areas,when the secondary standard of soil environmental quality standard(GB15618-2008)was used as reference,the contents of Cr,As,Ni and Cu in almost 6 coal mines,Zn,Cd and Pb were all less than 1,which belonged to the non-polluted grade.However,when the soil background value of Henan Province was used as reference,the contents of Cr,As,Ni,Cu,Zn,Cd,Pb,Tl single factor pollution index are greater than 1,are pollution levels.From the comprehensive pollution index,there is a certain degree of heavy metal pollution in the soil in the coal mining area,and the pollution degree is the highest.The pollution degree is CJ> CSL> XZ> FS> QS> XY.(4)The HQ value of heavy metal Cr in wheat flour in XZ coal mining area is very small,almost 0,which indicates that the local residents are taking the heavy metal Cr from the daily intake of flour.Ni,Zn and Cd are less than 1,indicating that the three kinds of heavy metals such as Ni,Zn and Cd do not affect the human body without significant health risk.The Cu and Pb in the flour are 38.89% and 11.11% of the HQ is greater than 1.This indicates that the body of the wheat flour in the process of intake of flour,Cu and Pb will have a significant health risk to the human body,should cause people vigilance.The value of HI in 77.78% of the wheat flour in the XZ coal field is greater than 1,indicating that there is a great possibility that the wheat flour in the XZ coal mining area will be harmful to human health.(5)The HQ values of heavy metals Cr in maize seeds of XY coal mines are very small,close to 0,or even almost 0,indicating that the residents around the study area have almost no absorption of Cr into the body after eating corn in daily life.The HQ values of Ni,Zn and Cd are less than 1,which indicates that Ni,Zn and Cd can not cause significant harm to human health under the condition of single ingestion.The 30% and 30% HQ of the heavy metal elements Cu and Pb in the corn seed were greater than 1,indicating that Cu and Pb in the maize seed of the coal mine would have a significant health risk to the human body during the ingestion of the corn seed,Should cause people to be alert.The HI value of 90.00% of the corn seed samples in the corn coal mine is greater than 1,indicating that there is a high probability that the corn seed in the XY coal mining area will be harmful to human health.