Study On Soils And Rice Polluted By Heavy Metals In Yancheng City

With the acceleration of urbanization, industrial residue and garbage of daily life has resulted in pollution of the soil environment, which endangered people's health. Heavy metal pollution and agricultural products security become the focus of our community. Yancheng City of Jiangsu Province.as the largest agricultural production base, is further planning to develop into safe and high quality organic agricultural products and green agricultural production base, therefore, research about heavy metal pollution of soil and rice in Yancheng city and evaluation of the impact on people's health is especially important.The literature review introduced the agricultural growth damage caused by heavy metal pollution; the health injury of consumers who eated the agricultural products of heavy metal contamination; the current trend of heavy metal detection technology.Through analyzing the content of heavy metal element in soil and rice of Dongtai. Dafeng, Yandu, Jianhu, Sheyang, Binhai in Yanchen City, we have several conclusions:(1) With the background value of Yangtze-Huaihe plain, criterion for green food production base. Safe Food production principle as standard, we analyzed soil heavy metal element content in 6 areas, using single pollution index and comprehensive pollution index. The results indicate that the soil of all areas was polluted, but still fulfill the requirement of green food production base. The soil pollution by heavy metals was significantly better than well-developed industrial city in South Jiangsu Province, we can create harmless agricultural production base in Yancheng City.(2) Results showed that the contents of seven heavy metal elements which include As,Cd,Hg,Pb,Cu,Zn.Cr in rice of Dongtai, Dafeng. Yandu, Jianhu, Sheyang, Binhai in Yanchen City, were lower than the national food safety standards prescribed limits. The contents of As,Hg.Pb,Cu,Zn,Cr were not significant between six areas, the Cd content of Yandu is highest, Binhai is lowest, the rest are middle.(3) Result indicated that As and Cd were the major metals which affect the quality of soil in Yancheng, As,Cd,Cu and Zn were the the major metals which affect the quality of rice in Yancheng.The enrichment ability of rice to Cd,Zn,Cu from soil is higher than other metals.(4) Related analysis shows that, in the rice of Yancheng City, the content of As was negatively related to the Cd, the content of Cd was positively related to the Hg,Cu and Pb. was positively related to the Zn,the content of Pb was positively related to the Cr, and the other were not significant correlation.(5) Comparing with the RfD value. USEPA limit, As,Cd in rice of Yancheng City were potentially risk to human health. Because the Cd in soil retaining capacity is weak, the reducing of soil pH will significantly improve the distribution of metal in the liquidoid of soil, and promote the crops absorption and accumulation on heavy metals.we can deduce that when soil acidification is a reality and trend for acid rain et factors in today, the Cd is greater potential pollution and food safety risk.