College of Environmental and Resource Sciences, Shanxi University, Taiyuan, 030006, PR China; Shaanxi Key Laboratory of Land Consolidation, Xi'an, 710064, PR China.
College of Environmental and Resource Sciences, Shanxi University, Taiyuan, 030006, PR China.
Chemosphere. 2020 Jul;250:126332. doi: 10.1016/j.chemosphere.2020.126332. Epub 2020 Feb 25.
Vermiremediation, which uses earthworms to remediate polluted soils, is an expanding technology in recently years. Surfactants have been widely used in bioremediation and other remediation technologies. However, the roles of surfactants in vermiremediation have been rarely studied. In this paper, an investigation of the effects of Tween-80 and rhamnolipid surfactant on the fluoranthene fraction distribution, vermiaccumulation, and removal during vermiremediation was conducted. Both Tween-80 and rhamnolipid improved the proportion of the desorbed fraction, bound residual fluoranthene, and correspondingly, proportions of the non-desorbed fraction were reduced. The vermiaccumulation of fluoranthene was significantly elevated by 35-64.1% and 34.5-44.2% by the Tween-80 and rhamnolipid, respectively. The vermiaccumulation of fluoranthene is positively correlated with the proportion of desorbed fraction of fluoranthene. Moreover, Tween-80 and rhamnolipid enhanced the removal of fluoranthene from contaminated soil during vermiremediation by 43.6-189.2% and 14.7-45.6%, respectively. The enhanced removal of fluoranthene was attributed to stimulated microbial degradation and increased vermiaccumulation resulting from the desorption ability of surfactants and earthworm activity. However, the total amount of fluoranthene that accumulated in earthworms was approximately 4-10% of the initial amount in the treatments, which suggested that microbial degradation rather than direct uptake contributed to the fluoranthene removal. The study suggests that the use of surfactants to enhance the efficiency of vermiremediation of polycyclic aromatic hydrocarbons (PAHs) contaminated soils might be feasible, and that surfactants-enhanced vermiremediation is an alternative strategies for treat PAHs contaminated soils.
蚯蚓修复是一种利用蚯蚓来修复污染土壤的技术，近年来得到了广泛的关注。表面活性剂已广泛应用于生物修复和其他修复技术中。然而，表面活性剂在蚯蚓修复中的作用却很少被研究。本文研究了吐温-80 和鼠李糖脂表面活性剂对菲的分配、蚯蚓积累和去除的影响。结果表明，吐温-80 和鼠李糖脂都提高了解吸部分的比例，结合了结合残留的菲，相应地，非解吸部分的比例降低了。与对照相比，吐温-80 和鼠李糖脂分别显著提高了 35-64.1%和 34.5-44.2%的菲积累量。蚯蚓对菲的积累与菲解吸部分的比例呈正相关。此外，吐温-80 和鼠李糖脂分别通过 43.6-189.2%和 14.7-45.6%的方式增强了蚯蚓修复过程中受污染土壤中菲的去除。菲去除的增强归因于表面活性剂的解吸能力和蚯蚓活动对微生物降解的刺激作用，从而促进了菲的去除。然而，在处理过程中，积累在蚯蚓体内的菲总量约占初始量的 4-10%，这表明微生物降解而不是直接吸收对菲的去除起主要作用。该研究表明，使用表面活性剂来提高多环芳烃（PAHs）污染土壤的蚯蚓修复效率是可行的，表面活性剂增强的蚯蚓修复可能是一种处理 PAHs 污染土壤的替代策略。
