核素示踪技术研究稀土元素^(147)Pm、^(141)Ce和^(147)Nd的环境毒理与安全性

STUDY ON ENVIRONMENTAI TOXICOLOGY AND SAFETY OF RARE EARTH ELEMENTS ^(147)Pm, ^(141)Ce and ^(147)Nd BY RADIONUCLIDE TRACER TECHNIQUE

应用核素示踪技术研究了稀土元素 ( 14 7Pm、14 1Ce、14 7Nd)的环境行为、生物富集性及其对动物性腺的影响。综合研究结果表明 :(l) 14 7Pm、14 1Ce和14 7Nd在土壤中具有强的吸附性 ,而且难以迁移 ,易于在土壤和底泥中积累 ;( 2 )供试的 5种水生生物、4种陆生食用植物对14 7Pm均具有明显的富集性 ;( 3) 14 7Pm、14 1Ce、14 7Nd在动物体内脏器和组织间呈不均匀分布 ,在骨骼、骨髓、眼、大脑、心脏、脂肪和睾丸中残留量较高 ,表现了明显的选择性蓄积 ;( 4 )一次性腹腔注射2 0 0mg·kg-1的Ce和Nd对小鼠性腺激素 (睾酮或孕酮 )的分泌有明显的抑制作用 ,以 2 0 0和80 0mg·(kg·d) -1的Ce随饲料摄入对雄性小鼠精子畸形率明显升高。本文从稀土的环境累积影响、与“环境优先污染”的类似性、动物脏器组织中的选择性蓄积效应及其天然放射性等方面探讨了农业应用稀土的环境安全性 。

The enviromental behaviour, bioconcentration of rare earth elements and their effects on animal gonad were studied by radionuclide tracer technique. The results indicated that (1) the 147Pm, 141Ce and 147Nd had strong adsorptivity in soil, so they were hard to transfer and easily accumulated in soil or sediment; (2) all the organisms (5 aquaties and 4 eatable plants) tested showed apparent 147Pm concentrating capabilities; (3)the residues of 147Pm, 141Ce and 147Nd were unevenly distributed in the animal's viscera and tissues, higher residues were found in bone, marrow, eye, brain, heart, adipose and testis, showing selective accumulation; (4) with intraperitioneal dosing of Nd or Ce 200mg ·kg -1 apparent inhibition to gonadial hormone (testosterone or progesterone) secretion in mice was found and with 200 and 800mg·(kg·d) -1 of Ce added in feed, the malformation rate of spematozoon showed higher. From the cumulative impact comparison between environment prior pollutants, accumulation effect of rare earth elements(RE) in animal's viscera and tissues and their natural radionuclide of RE were investigated on the safety of agricultural use of RE for eco-environment.