Alonso E, Santos A, Callejón M, Jiménez J C
Department of Analytical Chemistry, Faculty of Chemistry, University of Seville, Prof. García González, s/n. E-41012 Seville, Spain.
Chemosphere. 2004 Aug;56(6):561-70. doi: 10.1016/j.chemosphere.2004.04.031.
The Guadiamar river basin has traditionally received pollutants from two main sources: in its northern section of mining origin, and in its southern section (next to Doñana National Park) from urban-industrial and agricultural sources. In April 1998, the spill of 6 million m3 of mining wastes (acidic waters and sludge) severely polluted the Guadiamar river basin with heavy metals, which caused serious damage to the local ecosystem. There is a direct association between the physicochemical speciation of an element and its toxicity, biological activity, bioavailability, solubility, etc. This work describes a distribution study of the metals Zn, Cd, Pb and Cu by speciation analysis of surface waters in eleven sampling points of the Guadiamar river basin. Four metal fractions were determined using anodic stripping voltammetry: labile metal forms, H+ exchangeable metal forms, strongly inert forms (associated with organic and inorganic matter in solution), and forms associated with suspended matter. Total concentrations in surface waters followed the trend Zn > Cu > Pb > Cd. The speciation study showed that Zn and Cd were present to a large extent in available forms (labile and H+ exchangeable), while Pb and Cu were found mostly in the less available forms (strongly inert). Moreover, the available forms were found in the northern section (mining pollution) and the strongly inert forms in the southern section (urban, industrial and agricultural pollution). These results can illustrate the potential value of speciation to discern between different sources of pollution.
在其北部为采矿源，在其南部（靠近多尼亚纳国家公园）为城市工业和农业源。1998年4月，600万立方米采矿废料（酸性水和污泥）的泄漏用重金属严重污染了瓜迪亚马尔河流域，对当地生态系统造成了严重破坏。元素的物理化学形态与其毒性、生物活性、生物有效性、溶解度等之间存在直接关联。这项工作通过对瓜迪亚马尔河流域11个采样点的地表水进行形态分析，描述了锌、镉、铅和铜的分布研究。使用阳极溶出伏安法测定了四种金属形态：不稳定金属形态、H⁺可交换金属形态、强惰性形态（与溶液中的有机和无机物质相关）以及与悬浮物相关的形态。地表水中的总浓度遵循锌>铜>铅>镉的趋势。形态研究表明，锌和镉在很大程度上以可利用形态（不稳定和H⁺可交换）存在，而铅和铜大多以较难利用的形态（强惰性）存在。此外，可利用形态在北部区域（采矿污染）被发现，而强惰性形态在南部区域（城市、工业和农业污染）被发现。这些结果可以说明形态分析在区分不同污染来源方面的潜在价值。
