华东某铀矿区稻米中Cd含量及空间分布特征研究

利用等离子体质谱仪测定了某铀矿区周边稻米与对照区稻米中重金属元素Cd的含量,重点对铀矿区稻米中的Cd元素含量及其空间分布特征进行了研究。结果表明:(1)铀矿区内10.53%的稻米样品Cd含量超过国家标准,89.47%稻米样品中Cd的含量未超过国家标准(GB 2762-2005),而对照区稻米样品中Cd含量均远低于国家标准(GB 2762-2005);(2)铀矿区稻米中Cd含量远高于对照区稻米中Cd含量,尾矿堆积区、水冶厂和矿床开采区下游及周边区域内稻米中Cd元素含量明显高于上游地区或远离上述区域的其他地区。(3)矿床开采产生的废水与废渣、水冶厂的废液渗漏、尾矿露天堆积以及矿石运输过程中的矿渣洒落等原因可能是导致Cd元素随地表径流发生迁移进入稻田,从而使矿区稻米中Cd的含量较高的重要因素。

Study on Cd Content And feAtureS of itS SPAtiAl diStribution in riCe in A urAnium mininG AreA in eASt ChinA

By ICP-MS, this paper measured heavy metal Cd content in rice in the periphery of a uranium mining area and a contrast area, and focused on study of Cd content and its spatial distribution features, and concluded that: (1) 10.53% of rice in the uranium mining area has Cd content over national standard (GB2762-2005) and 89.47% not, while in the contract area, Cd content is far below the standard; (2) Cd content in rice in the uranium mining area is far more than that in contrast area, Cd content in rice in tailings accumulation zone, hydrometallurgical mill and lower reaches of mining area and the periphery is evidently higher than that in the upper reaches and distant areas; (3) waste water and residues from mining zone, waste liquid seepage from hydrometallurgical mill, tailings storage in the open air, and mineral falls from transport may be the major factor that leads Cd into rice field with surface runoff thus causing rice in the mining area to have higher content of Cd.