[ RadSafe ] Re: radsafe Digest, Vol 229, Issue 4

[Tupin.Edward at epamail.epa.gov]

Radsafers,

The issue at hand, as Jim Hardeman noted, is the potentially large
number of people exposed to radiation from fallout and possibly those
exposed to neutron and other prompt radiation from a very low yield
nuclear device (one in which the range of neutrons exceeds the blast
radius).

The interest is in separating people into three categories:  Those with
doses less than 1 Gy (100 rad); those with doses from 1 Gy (100 rad )to
5 Gy (500 rad); and those with doses  in excess of 5 Gy (500 rad).  I
use absorbed dose units here deliberately, as the issue is acute doses,
and the radiation weighting factors used for chronic worker dose
calculations are not appropriate.

The Interest is in identifying those in the middle group of the three
above.  These individuals will most likely be ill with acute radiation
syndrome.  Prompt and proper medical care will enable most of them to
survive.  Those in the low dose group will recover with minimal medical
attention.  However, many of them may mimic symptoms of radiation
sickness (nausea and vomiting) from stress or other non-radiation
causes.  Those with doses above 5 Gy have limited ability to survive
without heroic medical intervention, which may not be possible with
large numbers of victims.

Thus the emphasis on a rapid, simple method of determining doses using
biological markers.

Ed
Edward A. Tupin, MS, CHP
tupin.edward at epa.gov
Health Physicist
Center for Radiological Emergency Management
US Environmental Protection Agency  6608J
Washington, DC 20460
office: (202) 343-9383
cell: (202) 253-8206

Disclaimer:  this represents my personal opinion and is not the opinion
of the USEPA or the US Government.

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Date: Wed, 06 Jan 2010 19:56:58 -0500
From: "Jim Hardeman" <Jim.Hardeman at dnr.state.ga.us>
Subject: [ RadSafe ] Re: ASU leads $40 million effort to rapidly
             assess            radiation exposures
To: "Clayton J Bradt" <cjb01 at health.state.ny.us>,<radsafe at radlab.nl>
Message-ID: <4B44EB08.1E3F.005A.0 at dnr.state.ga.us>
Content-Type: text/plain; charset=US-ASCII

Clayton --

My first answer would be that the traditional non-stochastic tools we
currently have available (such as looking at the time of onset of
vomiting) are pretty imprecise when dealing with large numbers of people
in what will certainly be a high-stress environment. I certainly
wouldn't feel confident telling somebody that if they began vomiting
w/in an hour, that they might not make it -- or that if they don't vomit
w/in 5 hours that they'll probably be OK. In the case of fallout, I
don't know how one would even determine when exposure actually began.

I can't even conceive of doing lymphocyte depletion studies or dicentric
chromosome assays on a large population.

I agree w/ you that there's plenty of time to deal with the folks who
received non-stochastic doses.

My (additional) $0.02 worth ...

Jim

>>> Clayton J Bradt <cjb01 at health.state.ny.us> 1/6/2010 16:11 >>>

Jim Hardeman wrote:


...Based on the "Planning Guidance for Response to a Nuclear Detonation"
document, which I assume you have seen, it is entirely likely in a
nuclear detonation scenario that persons in the "dangerous fallout" zone
could get significant radiation doses w/o experiencing confounding or
more pressing medical issues -- and it's that population that public
health folks will need to be able to assess -- and quickly. What these
researchers are aiming for is the ability to rapidly assess the dose
received by perhaps a million people (or more) quickly ...
***************************

My question is: What's the rush? Massive acute doses will manifest
themselves by non-stochastic symptoms early on, and treatment given
promptly - if available. The stochastic effects from smaller doses
aren't treatable - so there's plenty of time to estimate doses.


Clayton J. Bradt
Principal Radiophysicist

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