Abstract The potential risk of increased metal concentrations through the application of composted wastewater sludge (CWS) is of concern. In particular, the high affinity of composted wastewater sludge for metals such as Pb, may influence the extent of metal uptake by plants. In this study, a sequential extraction protocol was employed to determine the fractionation and bioavailability of Pb, Cu, Cr, Cd, Zn, Ni, and Fe in CWS. To evaluate the influence of CWS on metal uptake, a fast growing plant Raphanus sativus L. (cultivated radish), was grown in CWS amended with perlite at four different compositions (0, 25, 50, 75, 100% w/w) treated with Pb and Cu. Plants were harvested after 3 weeks and analyzed for Pb and Cu concentrations. The extent of metal uptake, and intercompetitions between Cu and Pb upon application, at pH 7.3 and 5.8 was also assessed. Best growth was apparent at 25% to 50% (w/w) CWS composition, while an increase in the pH lowered Pb and Cu concentrations in plant tissues. Higher metal concentrations were found in roots vis-à-vis shoot or leaves. In was found that longer incubation periods of more than 3 weeks are needed for metal salts supplied in the inorganic form to be incorporated into the CWS structure and reduce their uptake.

中文翻译：

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堆肥废水污泥（CWS）对萝卜（Raphanus sativus L.）铅和铜吸收的影响

摘要 通过应用堆肥废水污泥 (CWS) 增加金属浓度的潜在风险值得关注。特别是，堆肥废水污泥对铅等金属的高亲和力可能会影响植物对金属的吸收程度。在本研究中，采用顺序提取方案来确定 CWS 中 Pb、Cu、Cr、Cd、Zn、Ni 和 Fe 的分馏和生物利用度。为了评估 CWS 对金属吸收的影响，快速生长的植物 Raphanus sativus L.（栽培萝卜）在用珍珠岩改良的 CWS 中生长，四种不同的成分（0、25、50、75、100% w/w）处理与铅和铜。3 周后收获植物并分析 Pb 和 Cu 浓度。在 pH 7.3 和 5 条件下，应用时金属吸收的程度以及 Cu 和 Pb 之间的相互竞争。8 也被评估。最佳生长在 25% 至 50% (w/w) CWS 组成时明显，而 pH 值的增加降低了植物组织中 Pb 和 Cu 的浓度。相对于芽或叶，在根中发现了更高的金属浓度。研究发现，以无机形式提供的金属盐需要超过 3 周的更长孵育期才能结合到 CWS 结构中并减少它们的吸收。