Study On The Detection Of Multiple Heavy Metals In Soil And Vegetables From Shijiazhuang Happy Farm By ICP-OES

This article selects YuXin Manor Farm is located in shijiazhuang city area, southwest suburb of JinGuo Farm and southeastern outskirts of YangGuang happy farm as the research object. Detection of Pb, Cr, As, Zn, Cu, Mn, Ni seven heavy metal elements in soil and vegetables from the three farms by ICP-OES. And the pollution status was analyzed. The main research contents are as follows:1)This topic has chosen Pb, Cr, As, Zn, Cu, Mn, Ni seven heavy metals as test object. Establish a new method of the detection of the seven heavy metals by ICP-OES. Through experiment we determined the seven heavy metals elemental characteristics of lines. And determines the optimum working parameters of the instrument are: high frequency generator RF power 1300 W, plasma gas flow rate of 15L/min, auxiliary flow rate of 0.3 L/min, atomizing air flow rate 0.55 L/min, the pump flow rate 1.5 L/min, peak area integration mode is observed from 15.0, axial observation mode is observation. Under these parameters, we can obtain good precision and accuracy of the test.2) To establish the best soil sample digestion method, selected the soil standard substance GBW 07410 which content close to the soil samples. Through compare the result of different digestion systems ultimately select the microwave digestion method as the pretreatment method for soil samples. Using this method the recovery rates of seven heavy metals in soil are between 91.8~107.6%.3) we established the best method of vegetable digestion by comparing test results under different ways using the standard addition method as control sample, and ultimately select microwave digestion method as the pretreatment method for vegetable samples. Using this method the recovery rates of seven heavy metals in vegetable are between 89.9~109.4%4)We test these seven kinds of heavy metal in soil and vegetables from the representative of YuXin manor farm,JinGuo farm and YangGuang happy farm using optimization of the test methods. The test results in the soil of these farms were: Pb content is between 28.2~35.5mg/kg, Cr content is between 60.6~82.1mg/kg, As content is between 9.0~10.9mg/kg, Zn content is between 59.8~94.9mg/kg, Cu content is between 22.2~38.8mg/kg, Mn content is between 378.9~589.2mg/kg, Ni content is between 21.0~42.9mg/kg, by comparing relevant national standards limit requirements, the heavy metals of these farms are able to meet the standards of 《Environmental quality standard for soils》, there is no heavy metal pollution situation. But a small amount of vegetable samples presence the phenomenon of Pb excessive, other elements are in line of standard requirements, which may be stronger Pb enrichment capability and atmospheric pollution and other factors.5)Through counting statistical the vegetable enrichment factor in soil, it can be concluded that the accumulation ability of heavy metal is different in vegetables, the enrichment capacity order is: Zn> Cu> As> Pb> Mn> Ni> Cr; and compared to different vegetables in the same place, we can see that heavy metal accumulation ability of different vegetables are significantly different, heavy metal accumulation ability of spinach is significantly higher than other vegetable samples; through the comparison of different farms, we find different farm soil affect absorb heavy metals of plants.