代谢
由于碲属于稀有的非必需微量元素，人们对其在人体内的肠道吸收和代谢行为知之甚少。职业医学所需的风险评估数据仅基于动物实验。为了研究碲在人体内的代谢行为，以不同形式给予健康的男性志愿者口服碲。它以碲酸钠、亚碲酸钠、金属胶体和固有结合在芥菜中的形式给予。对于后者，使用含碲的水培植芥菜，以便以更类似于食品的形式提供碲以供摄入。给药后，测定了碲的尿液排泄。使用石墨炉原子吸收光谱法（GFAAS）测量尿样中的碲浓度。从给药后前四天的累积碲排泄中，可以计算出可溶性碲盐的肠道吸收百分比为25% ± 10%。在给予六价碲后，肾碲排泄速度比摄入四价形式后更快。这可以解释动物实验中发现的四价碲化合物毒性更高的现象。将碲引入芥菜将肠道吸收降低到大约15%。对于金属碲，发现其肠道吸收分数约为10%。
As tellurium ranks among the rare non-essential trace elements there is only little known of its intestinal absorption and its metabolic behavior in humans. Data for risk evaluations needed for occupational medicine are based on animal experiments only. In order to investigate the metabolic behaviour of tellurium in man, tellurium in different forms was administered perorally to healthy male human volunteers. It was given as sodium tellurate, sodium tellurite, metallic colloid and intrinsically bound in cress. For the latter, cress was cultivated with tellurium-containing water in order to provide tellurium for ingestion in a form which is more equivalent to foodstuffs. After the administration the urinary excretion of tellurium was determined. Tellurium concentrations were measured in urine samples by means of graphite furnace atomic absorption spectroscopy (GFAAS). From the cumulative tellurium excretion in the first four days after the administration, a percentage intestinal absorption of 25% + or - 10% for soluble tellurium salts can be calculated. The renal tellurium excretion is faster after administration of hexavalent tellurium than after ingestion of the tetravalent form. This can explain the higher toxicity of the tetravalent tellurium compounds found in animal experiments. The introduction of tellurium to cress lowered the intestinal absorption to approximately 15%. For metallic tellurium the fractional intestinal absorption was found to be about 10%.
来源:Hazardous Substances Data Bank (HSDB)
