Muhlenberg College, Department of Chemistry, Allentown, Pennsylvania, USA.
Environ Toxicol Chem. 2011 Jan;30(1):112-23. doi: 10.1002/etc.357.
The effectiveness of surfactant formulations to remove aged metals from a field soil and their influence on soil toxicity was investigated. Batch studies were conducted to evaluate the efficacy of cationic (1-dodecylpyridinium chloride; DPC), nonionic (oleyl dimethyl benzyl ammonium chloride; trade name Ammonyx KP), and anionic (rhamnolipid biosurfactant blend; trade name JBR-425) surfactants for extracting Zn, Cu, Pb, and Cd from a soil subjected to more than 80 years of metal deposition. All three surfactants enhanced removal of the target metals. The anionic biosurfactant JBR-425 was most effective, reducing Zn, Cu, Pb, and Cd in the soil by 39, 56, 68, and 43%, respectively, compared with less than 6% removal by water alone. Progressive acidification of the surfactants with citric acid buffer or addition of ethylenediaminetetra-acetic acid (EDTA) further improved extraction efficiency, with more than 95% extraction of all four metals by surfactants acidified to pH 3.6 and generally greater than 90% removal of all metals with addition of 0.1 M EDTA. In two species of earthworm, Eisenia fetida and Lumbricus terrestris, metal bioaccumulation was reduced by approximately 30 to 80%, total biomass was enhanced by approximately threefold to sixfold, and survival was increased to greater than 75% in surfactant-remediated soil compared with untreated soil. The data indicate that surfactant washing may be a feasible approach to treat surface soils contaminated with a variety of metals, even if those metals have been present for nearly a century, and that the toxicity and potential for metal accumulation in biota from the treated soils may be significantly reduced.
研究了表面活性剂配方去除田间土壤中老化金属的有效性及其对土壤毒性的影响。进行了批量研究，以评估阳离子（1-十二烷基吡啶氯；DPC）、非离子（油基二甲基苄基氯化铵；商品名 Ammonyx KP）和阴离子（鼠李糖脂生物表面活性剂混合物；商品名 JBR-425）表面活性剂从经历超过 80 年金属沉积的土壤中提取 Zn、Cu、Pb 和 Cd 的功效。所有三种表面活性剂都增强了目标金属的去除效果。阴离子生物表面活性剂 JBR-425 最为有效，与单独用水相比，可将土壤中的 Zn、Cu、Pb 和 Cd 分别减少 39%、56%、68%和 43%。用柠檬酸缓冲液或添加乙二胺四乙酸（EDTA）使表面活性剂逐渐酸化，进一步提高了提取效率，用酸化至 pH 3.6 的表面活性剂提取了所有四种金属，提取率超过 95%，添加 0.1 M EDTA 时，所有金属的去除率一般超过 90%。在两种蚯蚓，赤子爱胜蚓和赤子爱胜蚓中，金属生物累积减少了约 30%至 80%，总生物量增加了约三倍至六倍，在经表面活性剂处理的土壤中，存活率增加到 75%以上，而在未经处理的土壤中，存活率仅为 75%。数据表明，表面活性剂清洗可能是一种可行的方法来处理受多种金属污染的表土，即使这些金属已经存在了近一个世纪，并且处理过的土壤中的生物毒性和金属积累的可能性可能会显著降低。
