Re: IAEA Safety Series #1 / Nbs #92 / NCRP #30

[David W Lee <lee_david_w@lanl.gov>]

Ken:

        The original radionuclide toxicity table was first published by the IAEA in its Technical reports Series No. 15, "A Basic Toxicity Classification of Radionuclides" (1963).  What the IAEA did was peruse the (MPC)-air (168-hr week) values for the various nuclides that had been listed in ICRP #2 and then arrange the nuclides into the "High", "Medium" and "Low" toxicity groups.  Presumably, the nuclides in the "High" toxicity group have much lower (MPC)-air (168 hr week) values than those in the "Medium" and "Low" toxicity groups.  Unfortunately, in 1960, when ICRP#2 was first published, no (MPC)-air (168 hr week) value was ever listed for I-125; I-125 was not addressed by ICRP #2.  The original IAEA table is entitled "Table 1 -- Radionuclides Arranged in Order of Their Most Restrictive (MPC)-air Value."  And my page 12 of my NCRP #30 does not list I-125 either.  I suspect that folks have been modifying the original IAEA Technical Series Report No. 15 table to fit their own purposes over the years such that the "latest" such table is but a mere shadow of its original self.  Happy hunting.  Please let RADSAFE know the identity of whatever "latest" toxicity table you find.

Best regards  David


At 10:46 AM 03/20/2000 -0600, you wrote:

Hi All -

I have a question on a table that is quoted numerous times in various
intuitions safety manuals. The table I believe was originally called
"Radiotoxicity Hazard from Absorption into the Body".  This table classified
certain common radioisotopes in to 4 Group (I Very High - IV Low)  based on
their radiotoxicity.

What I find interesting is that some nuclides first published in the NCRP
#30 as High Toxicity (eg. I-125) 1964 then get republished in IAEA Safety
Series number 1 1973 as Low toxicity. The latest attempt to sort
radionuclides into hazard groups I found in the Radionuclide and Radiation
Protection Data Handbook 1998. This publication took the exempt level stated
in IAEA safety series 115 and assigned a group level to it. It now assigns a
hazard group 2 (high) to I-125.

Does any one know where the latest revision of this table could be found? If
you have any insight as to where and how these tables were derived I'd like
to know?

Ken
Ken Smith, Radiation Safety Officer

Environmental Health and Safety (EH&S)  voice: (831) 459-3911
University of California                        fax: (831) 459-3209
1156 High St.                           e-mail: ksmith@cats.ucsc.edu
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Los Alamos National Laboratory
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