44 Campus Drive, Toxicology Centre, University of Saskatchewan, Saskatoon, SK, Canada S7N 5B3.
Chemosphere. 2012 Feb;86(5):521-9. doi: 10.1016/j.chemosphere.2011.10.018. Epub 2011 Dec 3.
In a previous study it was shown that pH significantly influences the release of metals from oil sands coke, particularly Ni and V which were identified as the cause of coke leachate toxicity. Coke comes in contact with oil sands process water (OSPW) during its transport to and long term storage in reclamation landscapes. However, the influence of dominant inorganic anions present in OSPW (i.e. HCO(3)(-), Cl(-) and SO(4)(2-)) on metals release from coke and on speciation and toxicity of Ni and V, has not been characterized before. Coke was subjected to a 15-d batch leaching process at four levels of HCO(3)(-), Cl(-) and SO(4)(2-) to determine the influence on metals release and speciation. Further, the effects of each of the three anions on Ni and V toxicity, as well as the mixture toxicity of Ni and V, were assessed using the three-brood Ceriodaphnia dubia test. Inorganic anions had a significant influence on the type and amount of metals released from coke. Specifically, sulfate increased the mobilization of cationic metals (e.g. Ni, Fe, Mn and Zn), whereas bicarbonate enhanced the release of oxyanion forming metals (e.g. Al, As, Mo and V) from coke. Chloride had no particular effect on the type and amount of metals released. With respect to toxicity, elevated bicarbonate levels decreased the 7-d Ni IC50 from 6.3 to 2.3 μg L(-1), whereas sulfate showed an ameliorative effect against V toxicity to C. dubia. In combination, Ni and V acted additively at their highest sub-lethal concentrations. Aqueous chemistry and toxicity of Ni and V are discussed with the goal of informing reclamation efforts at the Athabasca oil sands.
在之前的一项研究中表明，pH 值显著影响油砂焦从油砂焦中释放金属，特别是镍和钒，这被认为是焦浸出毒性的原因。焦在运输过程中与油砂工艺水（OSPW）接触，并在长期储存在复垦景观中。然而，OSPW 中存在的主要无机阴离子（即 HCO3-、Cl-和 SO42-）对金属从焦中释放的影响，以及镍和钒的形态和毒性，以前尚未进行表征。焦在四种 HCO3-、Cl-和 SO42-水平下进行了 15 天的批量浸出实验，以确定其对金属释放和形态的影响。此外，还使用三种 Ceriodaphnia dubia 试验评估了三种阴离子中每一种对镍和钒毒性的影响，以及镍和钒混合物的毒性。无机阴离子对从焦中释放的金属的类型和数量有显著影响。具体来说，硫酸盐增加了阳离子金属（如镍、铁、锰和锌）的迁移，而碳酸氢盐增强了氧阴离子形成金属（如铝、砷、钼和钒）的释放。氯对释放的金属的类型和数量没有特殊影响。就毒性而言，碳酸氢盐水平升高将 7 天 NiIC50 从 6.3μg/L 降低至 2.3μg/L，而硫酸盐对 C. dubia 的钒毒性表现出改善作用。联合使用时，镍和钒在其最高亚致死浓度下表现出相加作用。讨论了镍和钒的水化学和毒性，目的是为艾伯塔省油砂的复垦工作提供信息。
