Biological damage, blood for bioassays and inhaled quantities of U
March 5, 2007


Bioassays of the concentration of U in urine is used for determining
dose by reconstructing the quantity of the nuclides inhaled based on
the quantity in urine and its rate of elimination.

A lot of hocus pocus is used by official dose-reconstructionists,
based on questionable findings from lab animals and famous 1950's
human radiation experimentation to see just how fast and how much
(fraction) uranium is excreted in urine and feces after inhalational
uptake and ingestion.

Tissue specific doses can also be constructed by bioassaying the
specific quantity of U in the tissues and organs that "incorporate"
and "concentrate" radionuclides (lungs, bone, lymph, etc). Even less
is known about dose for these organs/tissues than the methods of
reconstructing dose from urine uranium excretion.

On the question of harm or damage, concentrations and quantity of U:

The ICRP/ICRU, the UN and all IEAE signatory nations' domestic
regulatory agencies (NRC, NRPB, CNSC, etc) use accepted (but
incorrect) rules for estimating dose and the risk of damage based on
concentrations of radionuclides and their urine excretion rates.

This is the crux of the issue:

No quantity of inhaled radionuclides is safe because quantum level
particle emissions damage the structure and functions of cells. One
atom of U can start a process leading to terminal cancer.

"Concentration" of radionuclides refers to the quantity per unit of
biological media or inert media; such as PPM refers to parts of the
material per million parts of the media. Uranium abundance in urine
is measured in nanaograms of uranium per litre of urine per 24 hours
of excretion. Urine uranium abundances and rates of excretion (i.e.
24 hour) provide parameters for comparing person to person, person
to baseline.

Public and worker urine uranium excretion rates are used to measure
public and worker risks and extrapolate into regulatory safety
standards (i.e. ALI's - allowable limits of intake are based on
excretion less retention converted to "burden" or dose remaining in
the body). This approach used world wide, may be correct in its
logic of process, but it is incorrect in its factors as it assumes
inhalational intake of U to be the same risk model as ingestion of
radionuclides.

That is what distinguishes the know-nothing from the know-somthing.
If regulatory dose models and rules are being used to discredit the
effects or risks to battelfield uranium residues, the foundation of
the arguement is flawed. Fahey, Diehl (WISE), DoD/DVA, DND, MoD, and
the NGWRC use this obfuscation tactic substantiate their claims that
there are no medical effects to DU.

Since the metabolic pathways are different (inhalation vs.
ingestion), the exposed and affected tissues are different and
residence time in the body is different. A pathway of the mouth
through the gastrointestinal tract to fecal elimination is a 24 hour
process. Inhalation to lungs to lymph or blood,
incorporation/ decorporation cycle, eventually to the liver and/or
kidneys for elimination is a cycle that takes years to decades. That
means, of course, exposure and risk are medical impacts are
significantly greater (at least statistically) .

"Residence time" or retention is the issue here. How much (what
fraction) of inhaled uranium remains in the body and for how long.
ICRP/NRC et al models severely underestimate the residency time (the
retention/excretion rates) of ceramic and ballistic uranium (238,
234, 235 and its accompanying synthetic nuclides of 236U, Pu, Am and
Np mixed in DU and NDU munitions).

Quantity is one factor but not the only; residence time - metabolic
pathway - solubility - radiation type and emission rate and the
incorporation/ decorporation cycles based on chemistry of the
radionuclide are all considerations.

It is fundamentally incorrect to say there is a "safe level". While
social engineers (i.e. the governments' HHS and public health
epidemiologists and actuaries) say "the more, the longer, the worse
the risk". The operational realities are different: there is no safe
quantity.

The regulations are determined by ALARA and insurance risk
assessments. Not by actual measurements of damage or studies that
might show the effects.

So, even though the abundance of U in the systemic circulation is at
mass concentrations of 10 e-18 or less - virtually undetectable by
mass spectrometers - the detectable quantities increase
significantly in the bodies concentrating tissues and fluids (i.e.
urine, lymph glands, liver, etc) - increasing to 10 e- 6, e-9 or -
12, where mass spectrometers can measure the abundance of each
uranium isotope and possibly detect the synthetic radioculides that
accompanies all battlefield uranium residues.

If (when) mass spectrometers were (become) sensitive enough to find U
in blood, the concentrations will still not represent dose because
the diffusion of the contaminant and the very short residency time
(exposure) the material has adjacent to tissues as it passes through
the circulatory system and there is not reference point for
abundance per quantity of carrying media per time (i.e. U/l/day).
There are no established U bioassay or dose models based on blood.