Dissolved organic carbon reduces uranium bioavailability and toxicity. 2. Uranium[VI] speciation and toxicity to three tropical freshwater organisms.
Dissolved organic carbon reduces uranium bioavailability and toxicity. 2. Uranium[VI] speciation and toxicity to three tropical freshwater organisms.
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DOI：
10.1021/es103349a
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发表时间：
2011-02
影响因子：
11.4
通讯作者：
Melanie A. Trenfield;J. Ng;B. Noller;S. Markich;R. A. Dam
中科院分区：
文献类型：
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作者：
Melanie A. Trenfield;J. Ng;B. Noller;S. Markich;R. A. Dam
评估了溶解有机碳 (DOC) 对铀 (U) 对三种澳大利亚热带淡水物种——北鳟鱼 (Mogurnda mogurnda)、绿水螅 (Hydra viridissima) 和单细胞绿藻 (Chlorella sp.) 的毒性的影响。暴露在不含 DOC 的合成软水中进行，并以标准苏旺尼河黄腐酸 (SRFA) 的形式添加 DOC。生物体暴露于一定范围的U浓度和一定范围的DOC浓度(0-20 mg L(-1))。与不含 DOC 的测试水相比，含有 20 mg L(-1) DOC 的水中的 U 毒性降低了 20 倍。还使用澳大利亚热带死水潭中含有 10 mg L(-1) DOC 的天然水来评估 U 毒性。相对于不含 DOC 的测试水，分流水中的 U 毒性降低了十倍。在同等 DOC 浓度下，SRFA 在降低 U 毒性方面的效果是分流水的两倍。地球化学形态模型证实，两种 DOC 来源导致的 U 毒性降低主要是由于与 DOC 络合导致游离铀酰离子 (UO2(2+)) 减少。为每种生物体提供了一个预测模型，可用于预测给定 U 和 DOC 浓度下的 U 毒性。
The influence of dissolved organic carbon (DOC) on the toxicity of uranium (U) to three Australian tropical freshwater species, the Northern Trout Gudgeon (Mogurnda mogurnda), green hydra (Hydra viridissima) and unicellular green alga (Chlorella sp.) was assessed. Exposures were conducted in synthetic soft water without DOC and with DOC added in the form of standard Suwannee River Fulvic Acid (SRFA). Organisms were exposed to a range of U concentrations at a range of DOC concentrations (0-20 mg L(-1)). U toxicity was up to 20 times less in water containing 20 mg L(-1) DOC, relative to DOC-free test waters. U toxicity was also assessed using natural water from a tropical Australian billabong containing 10 mg L(-1) DOC. U toxicity was up to ten times less in the billabong water, relative to DOC--free test waters. SRFA was twice as effective at reducing U toxicity as the billabong water at equivalent DOC concentrations. Geochemical speciation modeling confirmed the decreased U toxicity that resulted from both DOC sources was primarily due to a decrease in the free uranyl ion (UO2(2+)) through complexation with DOC. A predictive model is presented for each of the organisms that can be used to predict U toxicity at a given U and DOC concentration.