[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: background vs man-made emmissions - fallout
I can't remember for sure who told me the story I repeated below,
but I believe it was Phil Morrison about 40 years ago. He is not available
as a check. Does anyone know about the radiation levels in Hiroshima when
the Americans first arrived there after the war? I would like to get the
matter straight; there may have been a difference between Nagasaki, which
Ron refers to, and Hiroshima.
Bernard L. Cohen
Physics Dept.
University of Pittsburgh
Pittsburgh, PA 15260
Tel: (412)624-9245
Fax: (412)624-9163
e-mail: blc+@pitt.edu
On Wed, 3 May 2000, Ron L. Kathren wrote:
> I take strong exception to this anecdotal claim by my good friend Bernie
> Cohen, and would add to the excellent response by Tom Lashley a rather
> different anecdotal presentation written by long time HP Don Collins who
> entered Nagasaki shortly after the atomic bombing of that city: "I was able
> to trace the fallout from the bomb some 32 miles out to sea in one
> direction. It was about three times the normal background at that point."
> (Collins, D. L. "Pictures from the Past: Journies into Health Physics in the
> Manhattan District and Other Diverse Places, in Health Physics: A Backward
> Glance (Kathren and Ziemer, Eds.), Pergamon Press, 1980, p. 41.
>
> Ron Kathren
>
>
> ----- Original Message -----
> From: Bernard L Cohen <blc+@pitt.edu>
> To: Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
> Sent: Tuesday, May 02, 2000 6:52 AM
> Subject: Re: background vs man-made emmissions - fallout
>
>
> >
> > For some perspective on long term exposures from the Hiroshima bomb, I
> > remember a conversation with a scientist who was among the first to enter
> > Hiroshima after the bombing, with the job of using survey meters to look
> > for radioactivity. He was finding nothing for some time until he got
> > excited by a substantial positive reading. On investigating it, he found
> > that it was a medical source. Apparently, within the limits of survey
> > meters at that time, there was essentially no radioactivity from fallout
> > in Hiroshima.
> >
> > Bernard L. Cohen
> > Physics Dept.
> > University of Pittsburgh
> > Pittsburgh, PA 15260
> > Tel: (412)624-9245
> > Fax: (412)624-9163
> > e-mail: blc+@pitt.edu
> >
> >
> > On Sun, 30 Apr 2000 GlennACarlson@aol.com wrote:
> >
> > > I thought the existence of fallout at Hiroshima was well established,
> though
> > > the levels and the health impact are still debated. Is this incorrect?
> > >
> > > Consider also the following:
> > >
> > > Health Phys 1996 Sep;71(3):340-6; 137Cs concentration in soil samples
> from an
> > > early survey of Hiroshima atomic bomb and cumulative dose estimation
> from the
> > > fallout. Shizuma K, Iwatani K, Hasai H, Hoshi M, Oka T, Okano M
> Faculty of
> > > Engineering, Hiroshima University, Japan.
> > >
> > > Low background gamma-ray measurement has been performed to determine the
> > > 137Cs content in soil samples collected in a very early survey of the
> > > Hiroshima atomic bomb. These soil samples were collected just 3 d after
> the
> > > explosion within 5 km from the hypocenter and were not exposed to the
> global
> > > fallout from nuclear weapon tests. Out of 22 samples, 137Cs was detected
> for
> > > 11 samples, and their radioactivities ranged from 0.16-10.6 mBq g-1 at
> the
> > > time of the measurement. A comparison of the 137Cs deposition with the
> > > rainfall area within Hiroshima city indicates that the rainfall area was
> > > wider than the previously proposed one. Cumulative exposure by the
> fallout
> > > has been estimated to be 0.31 mC kg-1 (0.12 R) in Hiroshima city except
> for
> > > the heavy fallout area and at most 1.0 mC kg-1 (4 R) in the heavy
> fallout
> > > area.
> > >
> > >
> > > J Radiat Res (Tokyo) 1991 Mar;32 Suppl:32-9; Studies of radioactivity
> > > produced by the Hiroshima atomic bomb: 2. Measurements of fallout
> > > radioactivity. Hasai H, Hoshi M, Yokoro K Faculty of Engineering,
> Hiroshima
> > > University, Japan.
> > >
> > > Three studies of fallout measurements were reviewed for the discussion
> of
> > > possible radioactivity intake from the Hiroshima atomic bomb. The first
> study
> > > discussed correlations between enriched 234U and 137Cs specific
> activities
> > > from the measurement of soil samples collected in the "black rain" area.
> The
> > > second study measured 137Cs activity on the rock and roof tile samples
> > > collected in the hypocenter area immediately after the explosion. Some
> of the
> > > rock and roof tile samples collected near the hypocenter had a small but
> > > detectable amount of 137Cs activity. However, it has been determined
> that
> > > 137Cs exposure, for example, was negligible compared with DS86 dose
> > > estimates, since these activity levels were low. The third study
> detected
> > > 90Sr activity in some of the specimens of human bones exhumed on
> Ninoshima
> > > Island. This study compared the difference in activity between the bone
> head
> > > and shaft, with higher activities obtained in the bone head. This fact
> > > suggests a short intake period for this activity, however, the levels of
> 90Sr
> > > contamination were too low to allow a discussion of the exposure risks.
> > >
> > > In a message dated 4/30/2000 12:37:11 PM Central Daylight Time,
> > > frantaj@aecl.ca writes:
> > >
> > > > Subj: RE: background vs man-made emmissions - fallout
> > > > Date: 4/30/2000 12:37:11 PM Central Daylight Time
> > > > From: frantaj@aecl.ca (Franta, Jaroslav)
> > > >
> > > > Thanks for the information Glenn....
> > > >
> > > > ....but I'm very dubious about its veracity.
> > > >
> > > > The doses absorbed by the bombing victims are estimated to have been
> in the
> > > > range of a few hundred rem (depending on location, any shielding
> effects,
> > > > etc. (deaths were due to CONVENTIONAL thermal burns from the light
> flash
> > > and
> > > > from building fires, and from other forms of physical trauma, NOT due
> to
> > > ARS
> > > > !! ).
> > > >
> > > > Even if all of this exposure were due to neutrons - which it
> certainly was
> > > > not (there was a large gamma constituent) - it would have been very,
> very
> > > > far from sufficient to cause "High levels of residual radiation ...on
> the
> > > > ground...in the
> > > > > form of induced radioactivity produced secondarily as a result of
> the
> > > > > nuclear reaction of neutrons."
> > > > >
> > > > Trust me, its BS.
> > > > We have the recent example of the Tokaimura criticality accident,
> where the
> > > > absorbed doses were about ten times higher than those in Japan
> (actual
> > > > deaths from ARS), yet even there the levels of neutron-induced
> > > radioactivity
> > > > inside the building were negligible ( escaped airborne radioactivity
> was
> > > due
> > > > to vapours issuing from the precipitation tank containing the
> critical
> > > > solution of 20% U235 & FPs ).
> > > >
> > > > Radioactive fallout rain in Japan reportedly occurred, but far
> outside the
> > > > cities, after much dilution.
> > > > Any fallout soot from "intense firestorms" would NOT have been
> radioactive,
> > > > for the reasons given above.
> > > >
> > > > Glenn, the quotations you provide look to me like the same sort of
> > > > self-delusion that is practiced in the Ukraine and Belarus on account
> of
> > > the
> > > > Chernobyl disaster. Its amazing how many people believe THAT nonsence
> (tens
> > > > of thousands dead as a result, etc.). I take it you're NOT one of
> them ?
> > > >
> > > > Thanks again,
> > > >
> > > > Jaro
> > > > frantaj@aecl.ca
> > > >
> > > > > ----------
> > > > > From: GlennACarlson@aol.com[SMTP:GlennACarlson@aol.com]
> > > > > Reply To: radsafe@romulus.ehs.uiuc.edu
> > > > > Sent: Sunday April 30, 2000 12:01 PM
> > > > > To: Multiple recipients of list
> > > > > Subject: Re: background vs man-made emmissions - fallout
> > > > >
> > > > > _From http://www.city.hiroshima.jp/C/City/ABombDamage/07.html
> > > > >
> > > > > "7.2 Residual Radiation
> > > > >
> > > > > High levels of residual radiation were present on the ground for a
> > > certain
> > > > >
> > > > > period of
> > > > > time starting one minute after the explosion. Residual radiation
> came in
> > > > > the
> > > > > form of
> > > > > induced radioactivity produced secondarily as a result of the
> nuclear
> > > > > reaction of
> > > > > neutrons when initial radiation collided with the soil and building
> > > > > materials, and it
> > > > > also came from nuclear fission products and unfissioned uranium
> scattered
> > > > > by
> > > > > the
> > > > > bomb.
> > > > >
> > > > > It is quite likely that anyone entering the area within 1 km of the
> > > > > hypocenter within
> > > > > 100 hours after the explosion to search for people or help with
> relief
> > > > > efforts was
> > > > > affected by radiation coming from the soil and other such places
> due to
> > > > > induced
> > > > > radioactivity. In addition, soot and dust saturated with induced
> > > radiation
> > > > >
> > > > > from nuclear fission products and unfissioned uranium scattered at
> the
> > > > > time
> > > > > of the bombing were carried high into the atmosphere and later fell
> to
> > > the
> > > > >
> > > > > ground as radioactive fallout, giving rise to further possibilities
> for
> > > > > contamination.
> > > > >
> > > > > 7.3 Black Rain
> > > > >
> > > > > As the downtown area erupted in huge fires after the explosion,
> intense
> > > > > firestorms
> > > > > and whirlwinds developed. After 20-30 minutes, black rain began to
> fall
> > > in
> > > > > a
> > > > > wide area
> > > > > stretching from downtown to the northwest.
> > > > >
> > > > > Large amounts of fallout, referred to as "Ashes of Death" were
> contained
> > > > > in
> > > > > the rain
> > > > > in the form of radioactive soot and dust and caused contamination
> even
> > > in
> > > > > areas
> > > > > remote from the hypocenter.
> > > > >
> > > > > According to a study after the bombing, heavy rain fell in a 19km x
> 11
> > > km
> > > > > area and
> > > > > light rain fell in a 29km x 15km area, but there have been
> testimonies
> > > > > that
> > > > > black rain
> > > > > fell in places outside these areas as well."
> > > > >
> > > > > Glenn A. Carlson, P.E.
> > > > > glennacarlson@aol.com
> > > > >
> > > > > > Subj: RE: background vs man-made emmissions - fallout
> > > > > > Date: 4/30/2000 7:18:00 AM Central Daylight Time
> > > > > > >
> > > > > > > Regarding your comment, what about exposure from fallout?
> > > > > > >
> > > > > > > Glenn A. Carlson, P.E.
> > > > > > > glennacarlson@aol.com
> > > > > > >
> > > > >
> ************************************************************************
> > > > > > >
> > > > > > Reply : as far as I know, there wasn't any, since in both cases
> it
> > > was
> > > > > a
> > > > > > high-altitude explosion. This was confirmed by radiation
> surveyors on
> > > > > the
> > > > > > ground there soon after the explosions.
> > > > > >
> > > > > > Jaro
> > > > > > frantaj@aecl.ca
> > > > > > *************************************
> > > >
> > > ************************************************************************
> > > The RADSAFE Frequently Asked Questions list, archives and subscription
> > > information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html
> > >
> >
> > ************************************************************************
> > The RADSAFE Frequently Asked Questions list, archives and subscription
> > information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html
>
> ************************************************************************
> The RADSAFE Frequently Asked Questions list, archives and subscription
> information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html
>
************************************************************************
The RADSAFE Frequently Asked Questions list, archives and subscription
information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html