Study of health effects of inhaled rare metals and its preventive application

研究了两种不同粒径(平均直径分别为1和5μm)的稀土元素铈(Ce)和铕(Eu)可吸入颗粒物的生物行为。将氧化颗粒吸入雄性小鼠。染毒元素主要分布在肺内，较小颗粒组和较长暴露组的浓度较高，暴露后呈时间依赖性下降。Ce在其他器官中几乎检测不到，但Eu在肝、肾、脾和骨中也有分布，但其浓度远低于肺。暴露后，Eu在骨骼中的含量有所增加，表明Eu在其他器官中的一部分迁移到了骨中。由于未观察到肺部炎症，因此认为这些颗粒的肺毒性较低。这些结果表明，稀土颗粒物的有机分布取决于元素和暴露条件，并提示在工业卫生和预防中考虑这些因素是必要的。

Biological behavior of inhaled particles containing twokinds of rare earth elements, cerium(Ce) and europium(Eu), with different sizes(average diameter of 1 and 5μm) had been investigated. Oxide particles wereinhaled to male mice. Administered elements distributed mainly in lung, wheretheir concentrations were higher in smaller particle group and in longer exposuregroup, and decreased time-dependently after exposure. Ce was hardly detected inother organs, however, Eu was distributed also in liver, kidney, spleen and bonealthough the concentrations were much lower than those in lung. Eu concentrationsin bone showed some increase after exposure suggesting that a part of Eu in otherorgans moved to bone. Lung toxicity of these particles was thought to be lowbecause inflammation of lung was not observed. These results indicated that organdistribution of rare earth particles depended on the elements and exposureconditions, and suggested the necessity to consider these factors in theindustrial health and prevention.