Toxicity testing of heavy-metal-polluted soils with algae Selenastrum capricornutum:: a soil suspension assay
Toxicity testing of heavy-metal-polluted soils with algae Selenastrum capricornutum:: a soil suspension assay
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DOI：
10.1002/tox.20046
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发表时间：
2004-08-01
影响因子：
4.5
通讯作者：
Kahru, A
中科院分区：
文献类型：
--
作者：
Aruoja, V;Kurvet, I;Kahru, A
采用小型实验装置对重金属污染土壤悬浮液进行了月牙藻生长抑制试验。遵循OECD 201标准测试程序，并且通过提取的叶绿素的荧光测量藻类生物量。土壤中，其中含有高达（每公斤）1390毫克的锌，20毫克的镉，和1050毫克的铅在北方法国周围的铅和锌冶炼厂取样。悬浮液（1份土壤/99份水w/v）中金属的水可提取性与污染程度不成比例，因为污染程度较高的土壤样品的可提取性较低。因此，不同污染程度的土壤中，相同量的重金属可以被淋溶出来，说明土壤中重金属的总浓度（目前用于风险评估目的）是通过土壤-水路径的真实的环境风险的不良预测。（0.6-1.4 mg/L的锌在测试中），超过约10倍的EC 50值为S。capricomutum（0.1毫克锌/L），72小时的藻类生长在土壤提取物中是可比的或更好的标准控制OECD矿物介质中的增长。土壤悬浮液刺激藻类的生长高达八倍以上的增长使用经合组织控制介质。藻类的生长刺激，即使当土壤悬浮液中含有高达12.5毫克锌/L，不能解释补充氮，磷，和碳酸盐从土壤中沥滤。然而，如果藻类的生长在悬浮液中的清洁和污染的土壤进行了比较，对藻类生长的金属剂量依赖性抑制作用被证明。因此，由于土壤含有掩盖重金属不良影响的营养素/补充剂，因此应使用与污染土壤性质相似的清洁土壤代替矿物盐溶液作为土壤生态毒性分析的对照。(C)2004 Wiley Periodicals，Inc.
A small-scale Selenastrum capricomutum (Phapidocelis subcapitata) growth inhibition assay was applied to the toxicity testing of suspensions of heavy-metal-polluted soils. The OECD 201 standard test procedure was followed, and algal biomass was measured by the fluorescence of extracted chlorophyll. The soils, which contained up to (per kilogram) 1390 mg of Zn, 20 mg of Cd, and 1050 mg of Pb were sampled around lead and zinc smelters in northern France. The water extractability of the metals in suspensions (1 part soil/99 parts water w/v) was not proportional to the pollution level, as extractability was lower for soil samples that were more polluted. Thus, the same amount of metals could be leached out of soils of different levels of pollution, showing that total concentrations of heavy metals in soil (currently used for risk assessment purposes) are poor predictors of the real environmental risk via the soil-water path. Despite high concentrations of water-extracted zinc (0.6-1.4 mg/L of Zn in the test), exceeding by approximately 10-fold the EC50 value for S. capricomutum (0.1 mg Zn/L), 72-h algal growth in the soil extracts was comparable or better than growth in the standard control OECD mineral medium. The soil suspension stimulated the growth of algae up to eightfold greater than growth using the OECD control medium. Growth stimulation of algae was observed even when soil suspensions contained up to 12.5 mg Zn/L and could not be explained by supplementary nitrogen, phosphorous, and carbonate leached from the soil. However, if the growth of algae in suspensions of clean and polluted soils was compared, a dose-dependent inhibitory effect of metals on algal growth was demonstrated. Thus, as soil contains nutrients/supplements that mask the adverse effect of heavy metals, a clean soil that has properties similar to the polluted soils should be used instead of mineral salt solution as a control for analysis of the ecotoxicity of soils. (C) 2004 Wiley Periodicals, Inc.