Alvarez E Alonso, Mochón M Callejón, Jiménez Sánchez J C, Ternero Rodríguez M
Department of Analytical Chemistry, Faculty of Chemistry, University of Seville, Spain.
Chemosphere. 2002 May;47(7):765-75. doi: 10.1016/s0045-6535(02)00021-8.
The analysis of heavy metals is a very important task to assess the potential environmental and health risk associated with the sludge coming from wastewater treatment plants (WWTPs). However, it is widely accepted that the determination of total elements does not give an accurate estimation of the potential environmental impact. So, it is necessary to apply sequential extraction techniques to obtain a suitable information about their bioavailability or toxicity. In this paper, a sequential extraction scheme according to the BCR's guidelines was applied to sludge samples collected from each sludge treatment step of five municipal activated sludge plants. Al. Cd, Co, Cu, Cr, Fe, Mn, Hg, Mo, Ni, Pb, Ti and Zn were determined in the sludge extracts by inductively coupled plasma atomic emission spectrometry. In relation to current international legislation for the use of sludge for agricultural purposes none of metal concentrations exceeded maximum permitted levels. In most of the metal elements under considerations, results showed a clear rise along the sludge treatment in the proportion of two less-available fractions (oxidizable metal and residual metal).
对重金属进行分析是一项非常重要的任务，有助于评估来自污水处理厂（WWTPs）的污泥所带来的潜在环境和健康风险。然而，人们普遍认为，测定总元素并不能准确估计其潜在的环境影响。因此，有必要采用连续萃取技术来获取有关其生物有效性或毒性的适当信息。本文采用了一种根据BCR指南制定的连续萃取方案，对从五个城市活性污泥厂的每个污泥处理步骤收集的污泥样品进行分析。通过电感耦合等离子体原子发射光谱法测定污泥提取物中的铝、镉、钴、铜、铬、铁、锰、汞、钼、镍、铅、钛和锌。就目前关于污泥用于农业用途的国际立法而言，金属浓度均未超过最大允许水平。在所考虑的大多数金属元素中，结果表明，随着污泥处理过程的推进，两种较难利用的组分（可氧化金属和残留金属）的比例明显上升。
