Re Thorium Oxide

[P3D Peter Homer <P.J.Homer@xxxxxxxxxxxxxxxxx>]

John W Roberts mentioned Thorium Oxide in gas mantles and apparently it is
also found in camera lenses. The main thing about thorium oxide is that it
decays to the radioactive gas Thoron (Radon)  which is only an alpha
emitter but being a gas could easily be breathed in . There is a bit of a
scare on at the moment about natural levels of thoron building up in houses
built on thorium bearing rock. This has recently been linked to another
scare about cancer being caused by overhead powerlines. The theory is that
the associated magnetic field traps the alpha particles causing them to
build up . To try to get back on topic I dont think any thoron gas in glass
should be a worry as it would be trapped and quickly decays still further
also any alpha particles would probably not escape the  glass either .
After all incorporation into glass "Glassification" has ben suggested as a
way to neutralise radioactive waste. Gas mantles would seem to be much more
of a hazard but its a bit late to do anything now who uses gas mantles now
except perhaps in camping lanterns.     P.J.Homer



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