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Doc B
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I use to work in radiochemical development and production for the federal government and, while i cant vouch for all organisations, we use to send
feild staff out to contamined sights and private labs as a matter of course. You may need to develop an premise in order to gain both their attention
and cooperation but if you can do so you may be able to pick up some cheap or even free personal dosimetry devices from your local governing nuclear
regulator or scientific organization. These will monitor your exposure both whole body (lower limit) and peripheries (higher limit). If you get on
well with them they may even lend you the odd contamination device or perform ion chamber measurements etc for you.
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watson.fawkes
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Quote: Originally posted by annaandherdad  | | Cancer rates do vary from state to state, but I believe it's correct that none of it can be blamed on radiation. But I admit I don't know much about
this field (effects of low doses of radiation). |
Oh, please. I'm not anti-nuclear, but denying this linkage
is just ridiculous. This is from the page Radon and Cancer at the (USA) National Cancer Institute: | Quote: | | Radon is the second leading cause of lung cancer in the United States and is associated with 15,000 to 22,000 lung cancer deaths each year.
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Radon is an indoor air pollutant associated with the usual suspect mineral bodies nearby. Infiltration is
typically via diffusion through foundation walls, generated in subsoils. In some jurisdictions in the US, basement radon venting is mandated by code.
Now, about your sample. A few grams of thorium in a sealed bottle poses no particular risk, as long is it stays sealed in the bottle. Just ensure that
any place you work with it can be cleaned.
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annaandherdad
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OK, Watson, let me try to state it more carefully. When I worked with radiation (some time ago), they told us in the radiation safety classes we had
to take that there was no epidemiological evidence for increased rates of cancer due to cosmic rays (Denver vs New York, airline stewardesses/pilots
versus workers on the ground etc), nor due to the extra radiation from the soil for the people in India who live on top of thorium deposits. They
explained that that did not mean there was no effect, but that it was not visible in the large and noisy signal of cancers from all causes.
That was before the hazards of indoor radon were recognized. And yes, it is now believed that many or most lung cancer not caused by smoking is
caused by radon (at least that's my understanding of the current situation). As for the rest of it, it still seems to be true that the effects of
background radiation cannot be seen in the noisy and not-very-clean data on general rates of cancer. The poor quality of this data allows for
different interpretations, which seem to be biased toward whatever political position one wants to take.
One thing seems to be clear: whatever reasonable assumption you make about the effects of low level radiation, it does not begin to explain the large
observed cancer rates. Most cancers are evidently not caused by radiation. Nor does radiation explain the substantial differences in cancer rates
in different regions (different states). The case of lung cancer in nonsmokers may be an exception.
I have a friend who does research on the effects of radiation on biological systems. The effort is to understand the mechanism(s) by which radiation
causes damage, and thereby to give one more to work with when making hypotheses about the effects of low level radiation. I will ask him what his
opinion is of the current state of this field.
In the meantime, to return to thorium chemistry, I'm working on some graphs of various activities in the thorium decay chain, as a function of various
types of chemical separation, which I will post as soon as I have them.
Any other SF Bay chemists?
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watson.fawkes
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| Quote: Originally posted by annaandherdad | | One thing seems to be clear: whatever reasonable assumption you make about the effects of low level radiation, it does not begin to explain the large
observed cancer rates. |
That's also true. Radiation is not a general cause of cancer. Radiation from radon is
somewhat special, as radon deposits three alphas and two betas per atom directly into the alveolar tissue of the lung after inhalation. There's no
shielding the dosage. Ingested radionuclides also are known to cause cancer, though they aren't epidemiologically significant (not since radium
manufacture in phosphors was discontinued). There was a particularly egregious case of a radium-containing patent medicine (yes) that killed some by
cancer, but more by direct tissue destruction. I've heard stories about workers exposed to plutonium dust getting cancers in their feet, because the
particles are so dense they work their way down to the lower point of gravity. This is the real reason to worry about making dust that yields the
possibility of inhalation.
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