Volume 1

The nature of radioactive fallout and its effects on man : Hearings before the Special Subcommittee on Radiation of the Joint Committee on Atomic Energy, Congress of the United States, Eighty-fifth Congress, first session on the nature of radioactive fallout and its effects on man May 27, 28, 29, and June 3, 1957.

  • United States. Congress. Joint Committee on Atomic Energy.
Date:
1957-1958
Catalogue details

Licence: Public Domain Mark

Credit: The nature of radioactive fallout and its effects on man : Hearings before the Special Subcommittee on Radiation of the Joint Committee on Atomic Energy, Congress of the United States, Eighty-fifth Congress, first session on the nature of radioactive fallout and its effects on man May 27, 28, 29, and June 3, 1957. Source: Wellcome Collection.

    1034/1050 (page 996)
    nee oan like this. This is observed [drawing on the black- oard]. The effect would appear in this parabolic way showing a curve of this form. For the case of certain types of chromosome aberrations this is observed. | If we sce something which looks like this, the tipoff is that it 1s aiming at a point out on the dose axis which does look like a threshold. If we do not see that, then I think we have to presume as a hypothesis to work on and guide ourselves that it will indeed go straight down and will be linear. If it looks like it is linear up high, the probability 1s that it is linear down low. It is a very strange thing to explain a curve of the following form (drawing). I know of no interpretation of a curve which is linear in the upper part and ceases to be linear below. It is very queer. I know nothing about fundamental radi- ology that leads me to expect an effect of that kind. SoifIseea linear effect up high, then I suspect it is indeed linear all the way down. I notice that the usual effect in a class is taking place and a little diversion will not be harmful. I have what is getting to be the trade- mark of the biophysicist. These are on the market now as poppet beads. I can represent here one form of the key molecules of biology. This is a molecule of nucleic acid. It occurs in a long chain and it 1s doubled. On this chain are different colored beads indicated. They are the markers which determine our heredity and combinations in some manner of these are responsible for what conditions the nature of a cell and its future existence will be. What radiation can do is either break one of these in which case we have a partial chain, or it can break both. If both are broken, and this is a somewhat unusual event, and it may account for a little difference between cosmic rays and internally contained radiation, there 1s no simple agency of repair, not for a molecule. They may indeed repair and randomly perhaps they do. But if a break like this occurs and is perpetuated, then just as I will have trouble putting this back to- eether—and I do not want to take the committee’s time to do so—so will the cell have trouble putting it back together. The damage will therefore be in some measure permanent. The lack of our seeing permanent damage is partly the lack of our knowledge today. We do not know how to look. I would like to make an analogy between a person whose car has a convoy run into the side of it and scratches the paint. I can easily see that the people in charge of the convoy might say that the motor is not affected and the tires are all right, but if he did not know about the phenomenon of the paint rusting, he would not come to accurate estimate of the damage to the owner. The owner might in fact have sustained considerable damage to the car. It is the same today. We don’t yet understand how the cell works and how it is tied into the whole body. In fact, in the things that concern degenerative disease, we have almost no knowledge. We have very good knowledge on communicable disease, but in degenerative disease we are not so sure. I would like to submit that radiation does produce a scratch, and it always produces a scratch, and it would be a conservative and wise thing to say that we were not sure whether that scratch were important or not, and to then treat it as though it was, be- cause it might be like the paint on the automobile, it can run into a hundred dollars.