Re: Genetic effects of radiation on humans

["H.Wade Patterson" <hwade@triax.com>]

John Goldsmith wrote:
> 
> Wade:
>      The possible relevance of Neel et al. to LNT is unclear.  Neither is
> the finding a new one.  In Awa's Chapter on Genetic Effects in "The
> Effects of A-Bomb Radiation on the Human Body" (Shigematsu et al. eds) is
> the conclusion.:"Although an attempt was made to assess the genetic
> effects of aomic bomb radiation through the cytogenetic analysis of the
> offspring of atomic bomb survivors, the results failed to provide any evidence
> of genetic damage.  However, this does not preclude the possibility that
> radiation exposure causes an increased genetic risk, since it is necessary
> to consider various confounding factors."  The section goes on to cite
> Neel et al. as proposing a doubling dose value of 1.7-2.2 Sieverts,
> suggesting that this may be greater than for mice.  The final sentence
> "The genetic effect of radiation on humnans is currently inadequately
> understood..." The publication date is 1995, Harwood Academic Publishers
> for Bunkoda Co. Ltd. Tokyo      John Goldsmith
> On Thu, 10 Jul 1997, H.Wade Patterson wrote:
> 

Subject: Re: Genetic effects of radiation on humans
Date: Mon, 14 Jul 1997 08:35:05 -0700
From: "H.Wade Patterson" <hwade@triax.com>
To: radsafe@romulus.ehs.uiuc.edu

John Goldsmith wrote:
>
> Wade:
>      The possible relevance of Neel et al. to LNT is unclear.  Neither is
> the finding a new one.  In Awa's Chapter on Genetic Effects in "The
> Effects of A-Bomb Radiation on the Human Body" (Shigematsu et al. eds) is
> the conclusion.:"Although an attempt was made to assess the genetic
> effects of aomic bomb radiation through the cytogenetic analysis of the
> offspring of atomic bomb survivors, the results failed to provide any evidence
> of genetic damage.  However, this does not preclude the possibility that
> radiation exposure causes an increased genetic risk, since it is necessary
> to consider various confounding factors."  The section goes on to cite
> Neel et al. as proposing a doubling dose value of 1.7-2.2 Sieverts,
> suggesting that this may be greater than for mice.  The final sentence
> "The genetic effect of radiation on humnans is currently inadequately
> understood..." The publication date is 1995, Harwood Academic Publishers
> for Bunkoda Co. Ltd. Tokyo      John Goldsmith
> On Thu, 10 Jul 1997, H.Wade Patterson wrote:
>

John:

Thanks for taking the time to respond and for the additional citation.

My point in posting this material is to give examples of data that UBIN
have "overlooked" in their various reports on human radiation effects.

The citation I posted is only one example, and perhaps not the best, as
you have pointed out.

Here's another example of overlooked data which may be better. I'm
posting the entire abstract, so for those who have little time to read,
just focus on the 3rd and 4th sentences.

John, and all, best wishes,

Wade

Otake, M.; Schull, W. J.; Lee, S. Threshold For Radiation-Related Severe
Mental Retardation In Prenatally Exposed A-Bomb Survivors - A
Re-Analysis. Int. J. Rad. Bio, 70(6) :755-763; Dec.1996
Abstract:
Significant effects on the developing human brain of exposure to
ionizing radiation are seen among individuals exposed in the 8th-25th
week after ovulation. These effects, particularly in the highly
vulnerable period of 8-15 weeks after ovulation, manifest themselves
most dramatically as an increased frequency of severe mental
retardation. However, the distribution df cases of severe mental
retardation suggests a threshold in the low-dose region. The 95% lower
bound of the threshold in those survivors exposed 8-15 weeks after
ovulation was zero for the individual data based on the simple linear
model, and 0 . 15 Gy based on the exponential linear model used in our
previous report (1987), but the 95% lower bound of the threshold based
on all of the data including 21 additional cases with known doses
appears to be 0 . 05 Gy using the maximum likelihood estimates derived
from an exponential-linear model. The latter model was selected because
it provides the best fit from the standpoint of the stableness and
reasonableness of the estimates among the five models applied to the
data. When two probably non-radiation-related cases of Down's syndrome
are excluded from the 19 mentally retarded cases exposed 8-15 weeks post
ovulation, the 95% lower bound of the threshold is in the range of 0 .
15-0 . 25 Gy based on the exponential-linear model used in 1987, but is
in the range of 0 . 06-0 . 31 Gy when the more reasonable and better
model applied here is used. For exposure in the 16-25-week period based
on the same model, the 95% lower bound of the threshold changed from 0 .
25 to 0 . 28 Gy, both with and without inclusion of the two probable
non-radiation-related mentally retarded cases; one of these cases was
probably familial in origin since there was a retarded sibling, and the
other due to infection, since the individual had Japanese B encephalitis
at age 4 years.

mailto:hwade@triax.com

H.Wade Patterson
1116 Linda Lane
Lakeview OR 97630
ph 541 947-4974

-- 
Wade

mailto:hwade@triax.com

H.Wade Patterson
1116 Linda Lane
Lakeview OR 97630
ph 541 947-4974