Determination of artifactual formation of monomethylmercury (CH3Hg+) in environmental samples using stable Hg2+ isotopes with ICP-MS detection: Calculation of contents applying species specific isotope addition
Determination of artifactual formation of monomethylmercury (CH3Hg+) in environmental samples using stable Hg2+ isotopes with ICP-MS detection: Calculation of contents applying species specific isotope addition
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DOI：
10.1007/s002160050431
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发表时间：
1997-06-01
期刊：
影响因子：
--
通讯作者：
Evans, RD
中科院分区：
文献类型：
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作者：
Hintelmann, H;Falter, R;Evans, RD
各种提取技术，如蒸馏，酸和碱提取，已被测试的潜力，形成一个一甲基汞（CH 3 Hg+）的文物从无机汞在样品制备过程中。将Hg ~（2+）以富集稳定示踪剂的形式加入到不同的标准物质中，用HPLC/ICP-MS和GC/ICP-MS分析了该示踪剂中新甲基汞的形成。尤其是蒸馏法，更是容易形成伪影。由此产生的沉积物中甲基汞的高估高达80%。毛发、肝脏和藻类样品中的细菌形成不太显著，但仍可观察到。鱼肌肉组织显示蒸馏后没有伪影形成，但一些无机示踪剂在碱提取过程中转化为甲基汞。沉积物的酸提取导致低人工制品形成率。分馏测量的沉积物馏分显示高甲基汞形成率接近年底的蒸馏过程中，酸浓度在溶液中最高。本文提出了一种用种别同位素加入法（SSIA）校正甲基汞表观含量的方法，并给出了计算方案。
Various extraction techniques, as distillation, acid and alkaline extraction, have been tested with regard to their potential to form a monomethylmercury (CH3Hg+) artifact from inorganic Hg during sample preparation. Hg2+ has been added to different reference materials in the form of enriched stable tracers and the formation of new methylmercury from that tracer has been analyzed by HPLC/ICP-MS and GC/ICP-MS. Both techniques gave comparable results. In particular; the distillation technique was prone to artifact formation. The resulting overestimation of methylmercury in sediments was as high as 80%. Artifact formation in hair, liver and algae samples was less significant, though still observable. Fish muscle tissue showed no artifact formation upon distillation, but some of the inorganic tracer was converted to methylmercury during alkaline extraction. Acid extraction of sediments resulted in low artifact formation rates. Fractionated measurements of sediment distillates revealed high methylmercury formation rates towards the end of the distillation process when acid concentrations in the solution are highest. A technique for correction of the measured apparent methylmercury content applying species specific isotope addition (SSIA) is proposed and the calculation scheme is presented.