RE: Beer as a chelating agent for uranium

[denison.8@osu.edu (Eric Denison)]

Otto Raabe wrote:
>
>However, citric acid is not exhaled and is also has chelating properties,
>so juices might have some effect.
>
Citrate is indeed an excellent chelating agent, which is why it is part of
several anticoagulant compounds used in test tubes and collection bags for
blood products.  If I recall my medical lab training correctly, citrate
quickly and essentially irreversibly (at least under physiological
conditions) binds up calcium ions necessary for the proper progression of
the clotting cascade.  Not sure exactly how it reacts to heavy metals,
though, so I'd be a bit leery of using it for uranium unless I see data
that it binds heavy metals preferentially.

A word of caution -- side effects from large doses of citrate are fairly
common, especially if it is given IV.  Those of us who donate plasma and
pheresis products (platelets, leukocytes, etc.) take in the excess citrate
that hasn't gotten its fill of calcium when our red cells are returned
during the procedure.  Some folks suffer chills and tingling in the
extremities due to the action of the citrate on the metal ions still in the
general circulation.  Large enough doses could effectively scrub the blood
of circulating calcium and have a serious effect on the body's ability to
prevent and repair vessel damage.

Excessively large oral doses may lead to GI effects, and can in some cases
affect the pH of the blood.  When I worked in the Army hospital in Germany,
we saw a soldier who tried to speed his recovery from a cold by drinking OJ
by the gallon and overdosing on vitamin C tablets.  After a few days of
this, his kidneys could no longer handle the high concentrations of citric
and ascorbic acid, and began to shut down.  His blood chemistries were all
screwed up, and his urine had so much citrate in it that the stuff
precipitated out practically before the sample could cool from body
temperature.  The crystals were so numerous under the microscope that we
made training slides from his sample.  His urine pH was so low that we had
to dilute the sample by a factor of 100 to get the color block on the test
strip to show anything but its lowest value, which was 5.0 (remember that 1
pH point is a 10-fold change in H+ ion concentration).  Obviously, he
didn't return to duty right away.


Eric Denison
1729 Penworth Drive
Columbus OH 43229-5216
denison.8@osu.edu
(614) 433-0387


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