| Based on a large amount of datas which were monitored practically,the differences ofthe accumulation with the same heavy metal by the different plants and the differences ofthe accumulation of the same plant with the eight heavy metals were compared, and it hasimportant guiding meanings for tilting anti-pollution plant of heavy metal. With theregional datas practically monitored, the model of human health risk assessment on heavymetal pollution in soil was proposed, the uncertainty of the parameter in the riskassessment was controlled by a Monte Carlo simulation method,and the sensitive factorinfluencing the precision of the risk assessment was revealled. It was a good investigationfor the human health risk assessment through soil contamination of our country, and it hasvery important reality meaning for getting the information of the whole pollution conditionof regional soil in our country.The main contents of the paper were as follows:1. The differences of the accumulation with the same heavy metal by the different plantswas done by CHAID systemic cluster approach combining with nonparametricanalysis, and the hierachical cluster tree graphs of eight kinds of heavy metals wereoutputted. The vegetables were classified with five kinds, and the accumulation ability ofthe five kind vegetables were compared. And the result was in accordance with thestatistics result of the whole country done by Lijing.2. The differences of the accumulation with the eight kinds of heavy metals in the sameplant(rice, tea and rapeseed) were done by CHAID systemic cluster approach combiningwith nonparametric analysis. The cluster analysis of the accumulation ability of the eightheavy metals in rice was done, and the accumulation of Cd in rice was one clusterrespectivly, the other heavy metals were one cluster. The same cluster analysis of tea wasdone, Cd, Ni, Cu, Zn were one cluster, the accumulation of them were higher, the other heavymetals were one cluster, the accumulation of them were lower. The cluster analysis ofrapeseed was done too, and the beneficiations of Zn and Cd were higher, so they were onecluster, the other heavy metals were one cluster.3. Through the dietary exposure assessment of the health risk on heavy metals by a MonteCarlo stimulation method, the sensitive analysis of the exposure assessment was done, andthe daily exposure dose and its distribution figures were outputted. In the sensitive factor analysis of the vegetable exposure assessment, the sensitivity of every factor was done, andthe enrichment coefficient of heavy metals in the vegetables was the highest. Thecontribution of Cadmium exposure through vegetables to the human whole health risksbrought by Cadmium dietary exposure has been analyzed, and it was 84.42％. Thecontribution of the other heavy metals through eating vegetables can also be deducedthrough this method. The result of the exposure assessment was that the risks of Cr and Pbwas higher, but the other heavy metals were lower.4. The risks assessment of the health risk with heavy metals through diet by a Monte Carlostimulation method was done. The carcinogenicoty risks and health risks values throughrice, fruit and vegetables were exported and the distribution figures were outputted too. Theassessment result is simple and reliable, can reflect the reality. Among the carcinogenicotyrisks of the four kinds of heavy metals(As, Cd, Cr, Pb), only the risk of Cr is a little largethan that standard of 5×10-5·a-1 when it was 70％probability, consequently it caused thetotal carcinogenicoty risks higher than 5×10-5·a-1when it was 40％probability and the risksof the others were wery small, so the pollution of Cr should be controlled and treated. Thehealth risks of the eight kinds of heavy metals were all low, far lower than the Standard ofSweden Environmental Protection Agency and Department of Construction andEnvironment of Holland which was 10-6·a-1. In the proportion figure of the health risks ofthe eight kinds of heavy metals, the risk of As was the largest part and it was more than ahalf, the second were Pb and Cr6+,the proportion of the others were very small.5. The exposure risk the health risk were multifactorial analyzed.The two both showed thatthere was risk of Cr through diet, so the pollution of Cr should be treated. Pb hasneurotoxicity to children, and it has exposure risk in this text, so more attention should bepayed to it.
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