Re: alpha particles and lung cancer

[Bernard Cohen <blc+@pitt.edu>]

Zack Clayton wrote:

> Harry,
>
>  I think you are hung up on one of two components of most Radioactive decay.  Each decay will usually produce a particle and a photon.  the two most common particles are a beta (electron) particle and a photon (gamma), or in the case of very heavy nuclides, an alpha (2 protons, 2 neutrons) AND A PHOTON.  There are very few nuclides that produce only one component per decay.  I don't think anyone on this list has said that internal alpha radiation is good for you.  Period.  We are all trained that it is not.
>
> The hormetic value probably comes as part of the photonic portion of the decay.  This is the area that needs further study.  Life evolved in a richer energy soup than that present today.  To my knowledge, no one has published any studies on possible energy receptors sensitive to gamma wavelengths.

    The "photonic component" is truly negligible for most alpha emitters. It is far less than 1% for radon and the radon daughters. For U-238, it is 25% but the total energy for these is only  0.05 Mev vs 4.2 Mev for the alphas. Much of this 0.05 Mev is in internal conversion electrons and the rest is in very soft X-rays .

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