氚水在大鼠和小鼠体内的分布、代谢、转移及剂量估算

Distribution, Metabolism Transfer and Dose Estimation for Tritiated Water in Rats and Mice

本文汇总报道了氚水在大鼠和小鼠体内的分布、代谢、转移及剂量估算研究结果:(1)氚在小鼠体液及各组织中按指数下降规律呈均匀分布;(2)非妊娠鼠总氚的第一生物半排期约2 d,孕鼠和泌乳鼠分别约1.6和1.7 d,氚在母鼠、孕鼠和泌乳鼠体内的代谢规律基本一致;(3)大鼠组织中的氚活度分布不均匀,第15天组织中的滞留活度约占第1天的9%左右。(4)氚化小麦组大鼠组织内总氚和有机结合氚均明显高于氚水组;(5)氚水可通过受伤皮肤吸收进入体内,不同受伤程度的皮肤对氚的吸收率为切割伤>磨擦伤>烫伤>化学烧伤;(6)小鼠妊娠期和泌乳期母体内氚可通过不同途径转移给胎儿和仔鼠,转移系数在1.06~2.37之间;(7)小鼠母鼠、妊娠鼠和泌乳鼠总氚累积吸收剂量分别为8.5、6.7和7.1 mGy。

We studied the distribution and metabolism of tritium,and its transfer from mother to offsring,also estimated the absorption dose,in rats and mice.The results show that:1)tritium is evenly distributed in mice body fluids and tissues accroding to the law of exponential decline,and retention curves are generally resolved into two exponential components;2)the first biological half-life oftritium for non-pregnant mice is 2 days or so,while that for pregnant and lactating mice is about 1.6,1.7 days respectively,and metabolism of tritium in normal,pregnant and lactating mice is basically the same;3)the activity of tritium in the tissues of rats is unevenly distributed,and the retention on the 15 th day accounts for about 9%of that on the 1 st day;4)the total and organic tritium in the tissues of rats of the tritiated wheat group is significantly higher than that for the tritiated water;5)tritiated water can be absorbed into the body through the injured skin,and the importance of injury degree for absorption is cutting wound>scald>chemical burn;6)tritium in pregnant and lactating mice can be transferred to embryonic and newborn mice by different ways,with the transfer coefficient between 1.06 and 2.37;7)the cumulative absorption dose in normal,pregnant and lactating mice is 8.5,6.7 and 7.1 mGy respectively.