位于元素周期表中的34号元素,早在1817年就被瑞典化学家贝采列乌斯Be(?)zelius在硫酸矿铝室泥中发现,并命名为硒。意大利旅行家马可·波罗在游记中曾提到马群因采食了我国新疆的一种牧草后而发生中毒,以后证明是硒中毒。从此,人们一直认为硒是一种剧毒的微量元素。直到1957年Schwarz等人观察到,用0.1PPM的硒可防 Element 34, located in the Periodic Table of the Elements, was first discovered by the Swedish chemist Bechtelius Beelzem in the mud of the sulphate mines as early as 1817 and named Se. Italian traveler Marco Polo mentioned in his travels that the herd was poisoned after having ingested one of herbage in Xinjiang, China, and later proved to be selenium poisoning. Since then, people have always thought that selenium is a highly toxic trace element. Until 1957 Schwarz et al observed that selenium could be prevented with 0.1PPM