[ RadSafe ] " Technology to detect radiation has progressed "

[Geo>K0FF]

Naturally, anyone getting external beam therapy carries no radioactivity out 
of the hospital,
unless it is proton beam or boron capture neutron therapy,  etc. BUT:

Personally I am perplexed as to why patients are often not being given any 
kind of instruction concerning their
radioactive status when leaving the hospital or clinic.
Nowadays, radioactive tracers are used in a bewildering multitude of 
diagnostic procedures, and many of these
radioisotopes have significant radiological and biological half-lives. Never 
mind the actual therapeutic uses of internal radiological
material, seeds, wires, iodine, etc.
Many times patients are not ever told that their procedure included a 
radioisotope injection. They are never told anything
concerning radiation dose or dose/rate., feces, urine disposal issues etc.
Of the over 50 isotopes that I have discovered being used in medicine today, 
the most common by far are:

Tc-99m - 140 keV, 6.020 hour T/2. Used in a multitude of radio tracer 
tests.; Too numerous to mention.
F-18 - Positron, 511 keV annihilation photons, 109 minutes. Used in PET. 
10-20 milliCurie dose.
I-131, 364 keV, 8 days T/2. Used in thyroid diagnostics in tracer doses. 
Therapy in higher doses.

Thallium-201 is used for cardiac stress tests, but is being replaced by 
Tc-99m for better resolution. Tc-99m is the king of diagnostic tracers 
today.

There are at least 50 other isotopes used in diagnostics and therapy. Some 
day I will present a rather complete report on this subject

Patients given seeds, wires, iodine, etc. are of course radioactive for a 
long period of time, however,
compared to diagnostic uses of radioisotopes, therapy is rather rare. 
Diagnostics are very common now, as the new increased annual "average"
total dose indicated.
Gamma Rays, X-Rays of 140 to 511 keV can be easily detected at great 
distances and through walls and doors.
By far, the most abundant alarms in my mobile detection setup come from 
human beings. P.S. feline
thyroid disease is treated the same way as in humans, with radioiodine.

In my state of Missouri the DHSS (Department of Health and Senior Services, 
Bureau of Health Services Regulation, Missouri Radiation Control Program)
 has NO regulations or guidelines concerning radiation exposure to 
bystanders by patients being diagnosed. Tc-99m injected patients sit amongst 
the other persons in a common waiting room.
F-18 patients are segregated in separate waiting areas, but not because of 
radiation issues.
Nor is there any release criteria for diagnostic patients ( yes for 
therapeutic patients).
On any given day, I can go to the local clinic and measure a doserate of 5-6 
mR/H from F-18 injected patients (Gr-135),  total of 90 mR *external*
over the biological life (pen dosimeters) and much, much higher from Tc-99m 
patients.

Even the hallways measure an appreciable fraction of 1 mR/H with no patients 
even being there, just form medical storage
In our local clinic, the Tc-99m storage room shares a common wall with the 
main waiting room, with chairs right up against it.
Yes Tc-99m can be detected from those chairs.


These levels are low, but cumulative for people working in the area, none of 
whom are controlled or monitored in any way.

I for one would not want my grandchildren sitting for hours at a time at a 
ball game or movie next to someone who is putting
out a rather substantial and continuous radiation dose. Perhaps the 
increased "average" dose does not refer to people actually
getting the diagnosis, but the unaware members of the public next to whom 
they sit at ballgames.

Not a comment on safety etc. just sharing my actual experiences.

George Dowell
NLNL
New London Nucleonics Lab
GEOelectronics at netscape.com












----- Original Message ----- 
From: "Jaro" <jaro-10kbq at sympatico.ca>
To: "RADSAFE" <radsafe at radlab.nl>
Sent: Sunday, August 19, 2007 6:58 PM
Subject: [ RadSafe ] " Technology to detect radiation has progressed "


> Aviation Week & Space Technology
> 08/20/2007, page 26
> Technology to detect radiation has progressed, says Army Lt. Gen. William
> Webster, deputy commander of the U.S. Northern Command. During the most
> recent Little League World Series in Williamsport, Pa., detectors picked 
> up
> radiation from a fan entering the premises and handheld detectors guided
> officials to the fan's location. Upon questioning the fan, officials
> discovered she recently underwent radiation therapy for breast cancer and
> was still carrying residual amounts of the substance.
>