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

研究了不同粒径（平均直径为1 μm和5μm）含铈（Ce）和铕（Eu）两种稀土元素吸入颗粒的生物学行为。将氧化颗粒吸入雄性小鼠体内。给药元素主要分布在肺部，小颗粒组和长时间暴露组的给药元素浓度较高，暴露后呈时间依赖性降低。Ce在其他脏器中几乎检测不到，而Eu在肝脏、肾脏、脾脏和骨骼中也有分布，但浓度远低于肺。暴露后，骨骼中的Eu浓度有所增加，表明其他器官中的部分Eu转移到骨骼中。由于未观察到肺部炎症，这些颗粒的肺毒性被认为很低。这些结果表明，稀土颗粒的组织分布取决于元素和暴露条件，并建议在工业卫生和预防中考虑这些因素的必要性。

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.