The ability to determine mercury either as total or organic mercury below the parts per trillion (pptr) (ng L-I) level has become a major need in recent years. Researchers in Sweden and North America have shown that in aquatic environments, where mercury concentrations in the water column are often below the pptr level, the concentration of mercury in fish ranges from 0.5 to 2 μg /g (mainly as methylmercury).lS2 This is the result of two important processes: methylation of inorganic mercury and its biomagnification through the food chain. To understand these environmental processes (mercury chemistry, biotransformation, bioavailability, and bioaccumulation) quantification of the different species of mercury, in the water column, sediments, and biota is, therefore, a high priority.
近年来对于总汞或有机汞低于ppt级含量的检测需求成为主流。瑞典和北美国家的研究者发现，在水生环境中水中汞的含量通常在ppt级以下，而在鱼体内浓度在0.5-2μg/g间（主要以甲基汞形式存在）。这主要由两个重要过程：无机汞的甲基化和通过食物链生物放大。需对不同物种富集汞进行量化，以更好得了解这些环境过程（汞化学性质，生物转化，生物药效率，生物体内积累）优先考虑水体、沉积物和生物体。
In recent years, many methods for metallic mercury and organic mercury determinations have been published. A comparison of selected methods is given in Table 1. For total mercury the lowest absolute detection limit (DL), 0.09 pg, （was obtained in less than 1 min by laser-excited atomic fluorescence spectrometry with electrothermal atomization.) However, because of the small size of the sample to be used (only 10 μL), the detection limit in water was only about 9 ng L-l. For organic mercury determinations, most of the techniques are based on selective reduction (addition of an oxidative reagent vs no addition), complexing with organic molecules (ammonium tetramethylendithiocarbamate, 2-mercaptobenzothiazole,
et^.) and HPLC or GC separation (see Table 1).?
近年来，发表了许多测定金属汞和有机汞的方法。表1对一些常用方法作了一下对比。对于总汞的的{jd1}探测极限为0.09pg，（利用电热离解并通过激光激发原子荧光光谱法测定）。由于使用的试样量很小（10μL）水中探测极限为9ng/L。对于有机汞探测极限来讲，大多数技术基于选择性还原（加入氧化剂比之不加），与有机分子配位（XXXXX）和HPLC或GC分离。