SELENIUM BIOACCUMULATION AND SPECIATION IN CHIRONOMUS DILUTUS EXPOSED TO WATER-BORNE SELENATE, SELENITE, OR SELENO-DL-METHIONINE
SELENIUM BIOACCUMULATION AND SPECIATION IN CHIRONOMUS DILUTUS EXPOSED TO WATER-BORNE SELENATE, SELENITE, OR SELENO-DL-METHIONINE
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DOI：
10.1002/etc.624
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发表时间：
2011-10-01
影响因子：
4.1
通讯作者：
Libert, Karsten
中科院分区：
文献类型：
--
作者：
Franz, Eric D.;Wiramanaden, Cheryl I. E.;Libert, Karsten
本研究的目的是描述硒酸盐、亚硒酸盐和硒代蛋氨酸（硒- dl -蛋氨酸）在不同生命阶段的吸收和消除动力学，并利用x射线吸收光谱（XAS）确定硒的生物利用度与硒形态之间的关系。暴露于4.3 μ g/L溶解硒酸盐中10 d的蠓幼虫硒积累可以忽略不计（与对照生物没有区别）。然而，暴露于3.8和1.8 μ g/L亚硒酸盐和硒- dl -蛋氨酸（Se-met）的幼虫在10 d内迅速积累硒。暴露于亚硒酸盐或硒硒硒的幼虫在清洁水中消除10 d后仍保留了大部分硒。当其他蠓幼虫暴露于硒直至羽化时，幼虫期积累的硒大部分被保留在成虫体内。尽管羽化后成虫全身硒浓度与蜕皮中硒浓度有很强的相关性，但与幼虫和成虫全身硒浓度相比，蜕皮中硒的损失较小。x射线吸收光谱分析表明，有机硒化物和二硒化物（分别以硒met和硒半胱氨酸为模型）是昆虫幼虫期和成虫期硒的主要形式。硒硒酸盐和亚硒酸盐处理的幼虫和成虫体内有机硒化物（硒代蛋氨酸）的比例和浓度均高于硒酸盐处理，而硒半胱氨酸（硒半胱氨酸）的浓度在所有处理中均保持相对稳定。环绕。Toxicol。化学2011;30:2292 - 2299。(C) 2011自然
The objective of the present study was to describe the uptake and elimination kinetics of selenium (Se) administered in the forms of selenate, selenite, and selenomethionine (seleno-DL-methionine) in different life stages of the midge Chironomus dilutus, and to determine the relationship between Se bioavailability and Se speciation using X-ray absorption spectroscopy (XAS). Midge larvae exposed to 4.3 mu g/L as dissolved selenate for 10 d of had negligible accumulation of Se (indistinguishable from control organisms). However, larvae rapidly accumulated Se over 10 d of exposure to 3.8 and 1.8 mu g/L selenite and seleno-DL-methionine (Se-met), respectively. Most Se accumulated by larvae exposed to selenite or Se-met was retained after 10 d of elimination in clean water. When additional midge larvae were exposed to Se until emergence, Se accumulated during the larval stage was largely retained in the adults. Althotigh a strong correlation was found between the adult whole-body Se concentration and the Se concentration in the exuvia after emergence, only a minor loss of Se occurred in the shed exuvia compared with larvae and adult whole-body concentrations. X-ray absorption spectroscopy analysis showed that organic selenides and diselenides, modeled as Se-met and selenocystine, respectively, were the dominant forms of Se in both the larval and adult insect stages. The proportion and concentration of organic selenides (selenomethionine) increased in larvae and adults exposed to Se-met and selenite compared with larvae exposed to selenate, whereas the concentration of diselenides (selenocystine) remained relatively constant for all treatments. Environ. Toxicol. Chem. 2011;30:2292-2299. (C)2011 SETAC