Distribution, metabolism transfer and dose estimation for tritiated water in rats and mice

We studied the distribution and metabolism of tritium, and its transfer from mother to offspring, also estimated the absorption dose, in rats and mice. The results show that: 1) tritium is evenly distributed in mice body fluids and tissues according to the law of exponential decline, and retention curves are generally resolved into two exponential components; 2) the first biological half-life of tritium 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. (authors)