[ RadSafe ] RE: DU and other sublimed metals; nano-pathology

[CRGH Radiation Safety, Douglas Mackey]

Dear Radsafe
As a long time "lurker" on theRadsafe list I should like to thank James 
Salsman for bringing this flawed but still very interesting article to 
my attention. http://circ.ahajournals.org/cgi/content/full/105/4/411
My interest is in the observation of at least some level of transfer 
into the blood of insoluble particulates. I would however caution 
readers about ascribing any particular size to these particles without 
positive identification first.

 In "The observation of Fullerenes in a Technegas Lung ventilation unit 
-   Mackey et.al. Nuclear Medicine Communications (1994) 15, 430-434)" 
we show, using negative ion laser desorption fourier transform ion 
cyclotron resonance mass spectroscopy, that the Technegas generator 
creates carbon particles ranging from approximately 0.7 nm for C60 
Fullerenes (of mass 720)   up to Fullerenes with a mass to charge ratio 
of ~ 3000.

It was not possible -even using this powerful instrument- to positively 
identify Technetiums association with carbon in Technegas.

Theoretical modelling work indicated the favourability of the creation 
of even simpler compounds of  Carbon and Technetium. (Density Functional 
Investigation of Various states of the Molecules TcC, TcC2, ScC2 and YC2 
:  *P*.*Jackson*, *GE*.*Gadd*, *DW*.*Mackey*, H.van der Wall, and 
GD.Willett, J. Phys. Chem. A 102, 8941 (1998))

Having experienced the difficulty in identifying nm sized radio-labelled 
carbon particles, it doesn't surprise me that Nemmar et. al. state 
"However, we were unable to detect the carbon particles in ultrathin^ 
sections of blood by electron microscopy"

Regardless of other flaws in their technique which I mention below,  on 
the basis of their chromatography results I have to agree with the 
conclusion that some ultrafine insoluble carbon based particulates can 
rapidly diffuse into the systemic circulation from the lung.
The question is - How fine are these ultrafine particles?  How permeable 
is the lung membrane to TcC at mass 111 , in comparison to a 
hypothetical C60-99mTc metallofullerene at mass 819, or the pollutants 
mentioned by Nemmar et.al.- or the compounds under discussion on Radsafe?

James should also read Dr Burch's response in the same journal in 
November 2002: http://circ.ahajournals.org/cgi/content/full/106/20/e141 
where he points out that the Technegas generator used in this series of 
experiments was operating  in an clinically unacceptable manner. - i.e. 
producing a great amount of free pertechnetate. As Dr  Burch states, 
"There should be no visible thyroid^ on a study done using a properly 
functioning machine" 
I have confirmed this over many years while employing his invention for 
diagnosis at a number of institutions. As soon as thyroid begins to 
appear in clinical images from Technegas, we know that it is time to 
remove the built up deposit of salt crystals in the generator chamber. 
These crystals have a vast surface area on which oxygen may be adsorbed 
when the chamber is opened to air during generator loading.  During the 
generation of Technegas, a crucible is heated to over 2000 C in the 
chamber under an inert gas atmosphere. The resultant radient energy in 
the chamber can cause the release of the adsorbed oxygen resulting in 
contamination of the inert gas atmosphere. This prevents the proper 
formation of Technegas by oxidation of the carbon nano particles. The 
end result is the formation of free Pertechnetate (99mTcO4-) which is 
avidly taken up by the thyroid and rapidly washes out from the lungs 
into the blood.