Concentration Estimation Of Heavy Metals And Health Risk Assessment In Soils With Jiaojia Gold Mining Area

As one of the rare metals, gold has played an irreplaceable role in the international financial and industrial production, because of less abundant and unique physicochemical properties. Gold mining will inevitably lead to a series of environmental problems, such as ground subsidence, the heavy metal content in soil and dust pollution. The content of heavy metal elements in soil was measured by using chemical methods at present, but the traditional chemical methods take a large cost and the application surface is small, unable to carry out monitoring large areas, greatly limits the real-time monitoring of the surrounding soil environment in mining area. So it is a hot current research direction about how fast and efficient for heavy metals in soil around the mining areas to monitor, and predict heavy metal elements on human health hazard rating. The high spectral remote sensing technology provides a new way to monitor the content of heavy metal elements in the soil with its precise resolution and get real-time data, and also it provides the data base for calculating the risk value of heavy metal elements to human health hazard.This study takes Jiaojia gold mining area as the main research area, with the support of National Natural Science Foundation of China: ‘A Remote-sense Monitoring Study of Farmland Ecological Safety in Sewage Irrigation Area Based on Surface Parameters', ‘Remote sensing monitoring of Longkou mining area and the surrounding coastal zone', ‘Geological remote sensing monitoring of Jiaojia gold mining area and the surrounding area in Shandong Province', ‘Investigation of the Yellow River Delta efficient ecological economic zone(Weifang) sea salt water intrusion and build monitoring and early warning system' and ‘The construction of Shandong province land resources remote sensing spectral library', combined with hyperspectral remote sensing technology and statistical analysis, inversion to the prediction of soil heavy metal content of Jiaojia gold mining area and the surrounding area, the contents of heavy metal elements in the soil of the study area were obtained. At the same time, by means of the health risk model, the risk level of heavy metals in Jiaojia gold mining area to human health were calculated. The main contents and results of the research were as following:(1) 43 sampling points were arranged in the study area, selected 30 sampling points to measure soil spectral information and the content of heavy metal elements in the laboratory, and establish the multivariate regression model. Through the testing, the most suitable model for Cu and Zn was continuum-removal model. Reciprocal logarithmic model was the most suitable model of Hg, As, Pb. The first-order differential model was best suited to Cr.(2) Through the regression model of each element to inverse heavy metals content in surplus sampling points, using statistical analysis to obtain the spatial distribution of heavy metal elements. The test found that the content of Cu, Hg, As, Cr, Pb and Zn were in the range of 10.4-33.5, 0.048-0.085, 3.5-26.9, 26.4-91.6, 19.2-37.9, 30.1-80.9 mg/kg respectively. Higher levels of heavy metals were located in the Midwest, Eastern and Northeastern. To compare the standards of national secondary soil organic pollution, all heavy metals content in the study area did not exceed the standards.(3) Combined with the spatial distribution of heavy metals and health risk model, the risk level of heavy metals on human health in the study area were as follows: The As element of risk rating for the I level, Cr element risk level II and III and Cu, Hg, Pb and Zn elements were less than I level risk level. After comprehensive evaluation, the risk level of heavy metals content of Jiaojia Gold Deposit to human health was II and III.(4) Although heavy metal elements in Jiaojia gold mining area is not obvious, the trend of aggregation and accumulation had been appeared. It can cause harm to human health. Therefore, this need to attract people's attention and in the next step of the mining process to take relevant measures.