At 09:28 PM 12/9/2012, Eric Walker wrote:
On Sun, Dec 9, 2012 at 4:37 PM, Abd ul-Rahman
Lomax <<mailto:[email protected]>[email protected]> wrote:
Well, think about it, Axil. The button is a
circular piece of metal, probably steel. It has
a well in it, shallow, as I described. At the
bottom of the well, there is what looks like,
under magnification, some kind of "smear" of
something. It would be americium oxide, which is
insoluble. You can swallow this stuff,
apparently without harm, because it does not
dissolve with stomach acides. This would be 0.9
microcurie of Am-241, which is really tiny.
Â
I think a danger with alpha sources is inhaling
them in powdered form or when they are deposited
on airborne dust or vapor, such that they become
lodged in the lungs. Â Also, americium seeks
bone if it enters the blood, where it remains for a long time [1].
Eric
[1]
<http://www.atsdr.cdc.gov/toxprofiles/tp156.pdf>http://www.atsdr.cdc.gov/toxprofiles/tp156.pdf
That source is pretty redunant, saying the same
thing over and over. However, it did eventually
acknowledge what I long ago heard: people have
swallowed Am-241 sources, in the one microcurie
range, with practically no untoward effect. They
measured the level to which the Americium oxide
or dioxide in the sources dissolved, by looking
for it in the urine. The levels were extremely small.
Some guy was unfortunate enough to have a whole
device blow up in his face, severely lacerating
him and blasting maybe a hundred curies of Am
into his body. He was treated with massive
chelation therapy, and survived for eleven years,
dying from unrelated causes. They really followed
this guy, because you can't run experiments like this on humans!
He had some damage, all right. But it's not what
killed him. He was pretty old at the time of the accident, I think he was 66.
Am-241 sources for ionization smoke detectors are
0.9 microcuries. That amount of Americium, if
somehow made airborne and absorbed into the
lungs, could be a problem, for sure. But you'd
really have to work to get it to do that. For
starters, the oxide isn't terribly harmful on the
skin or swallowed. Other compounds are much more
effective at getting into the body and staying
there, the nitrate, for example, has been studied with animals.
So I have an envelope on my desk here, with an
Am-241 button in it. It's actually a bit more
than the tiny button shown on that youtube video
that someone posted, of a woman who dismantled a
source. I think that my source is actually a
piece of metal (I've thought it was steel, but
some have claimed that these sources are mounted
on aluminum; mine based strip of metal seems too
strong and too hard to be aluminum, but I've not
really investigated this.). I'd rather keep the
source mounted. Harder to swallow, harder to
lose. If the actual button fell on my floor, it would be pretty hard to see.
I've described the source as being a smear of
material in the bottom of the well. However, that
might not be true. What I see under magnification
is an area of shiny material, with an irregular
boundary, striated, in the middle of the bottom
of the well, largely filling it. But surrounding
this is a dark area that is not striated. That
does not look like metal, whereas the middle of
the bottom does. I'm thinking that the Am-241
oxide (dioxide?) might be the dark material, up
against the wall of the well. That would make it
even harder to accidentally scrape some out. A
bit more of the radiation would be absorbed by the walls of the well.
I'm much more concerned about my piece of
Beryllium. It's got something that looks like
grime on two edges. Wiped onto a tissue, that
appears to be a very dark powder, under
magification, the particles seemed very small,
relatively uniform in size. Very tiny black
specks. I strongly suspect that someone took some
bar stock and cut it to make these pieces. And
did not ensure that they were left clean. I've
asked the seller. No response so far.
If the seller did the cutting, and did this
extensively, he risked his own health and may
have contaminated some equipment.... I saw no
clue in any of his information that this was a
hazardous material, which is worrisome all by
itself. I was, myself, I assume, exposed to a
little of this, a speck or two might have flown,
but that level of exposure, if not repeated over
time, is not terribly dangerous. The specks are
not seen on the plastic bag the piece was
enclosed in, so they are not "loose" until wiped off. They might be oily.
I'll keep the Beryllium in its plastic bag for
now. Before using it, I'll need to clean it, I'll
think about how to do that safely. The total
amount of contamination here, if those particles
are Be, is very small, I need to keep it from
becoming airborne. I don't think I need to call
in the hazmat team! There is a lot more Be
floating around from beryllium brakes from
certain aircraft.... and other sources.
