[ RadSafe ] Uranium and genotoxicity

[Dan W McCarn]

Hello:

Switch and bait, switch and bait: James, can you not stick to one issue.  Fathallah (2007) focused his specious argument on uptake of DU into plants as well as water in "Southern Iraq" as the uranium .  

To quote Fathallah: “The fine uranium dust has been spread by the wind from the war zone to the surrounding region, including Basrah, and it is by now pushing down the soil by the effect of rain to reach the water table, which is used for drinking & irrigating the vegetables for human consumption 34.”

So, 
1) Fathallah assumes airborne distribution of uranium (not that left as metal in the ground).
2) The much smaller, fractional area used for irrigated farming.

Analogs:
The irrigated area of the San Luis Valley is 179,613 hectares (1,796.13 Sq. Km) producing about 2 million tonnes of crops each year for both human and animal consumption (McCarn, 2004, IAEA TECDOC 1396).  Almost 1 million tonnes are potatoes.  I estimate that approximately 7.5 ± 2.5 Tonnes U per annum source term are applied to these crops based on average U concentration and total consumptive water use of those crops (probably an underestimate of total water applied).  Of course since the uranium is derived from natural sources of uranium, it's "contaminated" with uranium progeny, and can no longer be directly compared to DU since it also contains 234U, 226Ra as well as 2-3 kCi of 226Rn evolved from the spray irrigation systems.  Of course, I've left-out of my estimate the considerable amount of phosphate fertilizer annually applied to these soils which will also contains uranium.

Does this seem a reasonable analog?

I doubt that you will be able to find much on caliches and uranium, unless you can find one of those rare copies of Donald Carlisle et al 1978 (Jan 6, 1978) exhaustive 274 page monograph (not including scores of maps and figures) entitled "The distribution of calcretes and gypcretes in the southwestern United States and their uranium favorability, based on a study of Western Australia and South West Africa (Namibia)", U.S. DOE contract number 76-022-E.  Then you will have to figure-out the difference between a pedogenic and non-pedogenic calcrete.  By the way, Donald doesn't mention it in the title, but uranium is also concentrated in silcretes as well.

As a geologist, I'll stick mainly to geological topics and areas of first-hand knowledge such as the more than two decades of letters from my sister-in-law, while you James, having had no background, and no "first-hand knowledge" seem to be expert in everything.  What is your degree in?

Dan ii


-----Original Message-----
From: jsalsman at gmail.com [mailto:jsalsman at gmail.com] On Behalf Of James Salsman
Sent: Saturday, June 07, 2008 1:25 AM
To: Dan W McCarn; radsafelist
Subject: Re: [ RadSafe ] Uranium and genotoxicity

Dan,

Thank you for your message.

What is your opinion on whether (U-238)O2-Y is more dangerous than
(U-238)O3-D, as the ICRP and NRC assert, or does the bioavailability
of the uranyl ion make equivalent activities of (U-238)O3 more of an
ingestion and inhalation hazard?

> James is persistent; I just wish that he would listen.
> My presentation of moles per liter of PHREEQC
> equilibrium concentrations has been previously presented.

I wish you would listen, too.  When will you use the 25,000 km^2 area
in which depleted uranium munitions were used instead of "a third of
Iraq," which is several times larger?

Furthermore, have you taken into account that potable water in that
region is taken from rainwater runoff?

>... Also consider that groundwater may also have
> a number of other trace metals and materials,
> e.g. major anions & cations (Na, Ca, Cl, SO4,
> HCO3, CO3) trace metals (selenium, molybdenum,
> etc. that may concentrate in the soil zone over time.
> It all depends on the "Leaching Coefficient", how
> quickly or slowly specific analytes move through
> the soil column.

Does that imply that mathematical models require a firm foundation in
empirical observation from weathering of the oxides to human
bioavalability on the specific terain in question?

> The fact is that the uranium does not concentrate
> significantly in desert soils with the possible
> exception of caliche- or gypcretes-forming soils....

I will have to look those up.

In the mean time, would you please have a look at this article and
please tell me your opinion of it?
  http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2137136

James Salsman