Re: Release of I-131 Patients

["J. J. Rozental" <josrozen@netmedia.net.il>]

At 05:59 PM 10/31/99 -0600, you wrote:
>At 10:27 A 29.10.1999 -0500, Elizabeth Brackett  wrote:
>>>>It seems that I have heard of a couple of facilities that have attempted to
>>>measure external dose equivalents to the family members of I-131 patients by
>>>issuing film or TLD badges to those family members.  Anyone know about this
>>>and if so, where we can view the results?  That would be interesting.
>>>
>
>There have been a number of studies.  The best ones are probably
>
>Barrington SF et al  "Radiation exposure of the families of outpatients
>treated with radioiodine (iodine-131) for hyperthyroidism" Eur J Nucl Med
>1999 26:686-692
>
>51 patients given activities given 200 - 600 MBq.  95% of adults complied
>with the 5 mSv limit (range:0.2-5.8 mSv) and 89% of children with the 1 mSv
>limit (range: 0.2-7.2 mSv)
>
>
>Monsieurs M et al  "Real-life radiation burden to relatives of patients
>treated with iodine-131: a study in eight centres in Flanders (Belgium)"
>Eur J Nucl Med 1998 25:1368-1376
>
>13 patients given activities (3700 - 5500 MBq) for thyroid cancer, 52 given
>(18- 1665 MBq) for thyrotoxicosis. Partners of cancer patients received
>0.14-0.94 mSv, children received 0.28-1.09 mSv during the first 14 days
>post-therapy.
>
>Please note that the guidelines for discharge of patients in Europe is very
>different from the US.  In the case of the study from Belgium, patients
>were hospitalised until the dose rate at 1 m was less than 20 uSv/h.  This
>equates to approximately 500 MBq retained activity.
>
>Regards
>
>Richard
>
>
>
>Richard Smart PhD
>Principal Physicist & Radiation Safety Officer
>Department of Nuclear Medicine
>St. George Hospital
>Kogarah, NSW 2217
>Australia
>Tel:61 2 9350 3112
>Fax:61 2 9350 3991
>Email:R.Smart@unsw.edu.au
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>

==================================
Richard,

I think that in Australia, at least a couple years ago,  also the discharge
for patients in theraphy of I-131 was about 500 MBq (15 mCi). There was
change on this guidance level?
In Brazil we follow the IAEA Basic Safety Standards, Safety Series 115,
1996. According with the table III-VI page 284 the I-131 the activity for 
discharge from hospital is 1100 MBq (30 mCi). The table also mention "In
some countries a level of 400 MBq (10 mCi) is used as an example of good
practices". Among these countries,  that use less than 30 mCi, I can mention
Scandinavia, German, Switzerland, Australia,  (RADSAFERS from these
countries can confirm if still it is less than 30 mCi the I-131 activity at
which may be discharged from hospital).

Taking into account  the above expression: "In some countries a level of 400
MBq (10 mCi) is used as an example of good practices" can we conclude that
above 30 mCi is example of bad practice?

I can recomend also a interesting document, not about the control of
external exposure, but data about Internal exposure. Please GO TO:

http://www.uni-koeln.de/~ainu2/papers/badgas98/index.htm

"Internal exposure to relatives of radioiodine therapy patients from I-131
inhalation at home"

W. Eschner, U. Wellner, H.W. Hillger and H.Schicha
Clinic for Nuclear Medicine, Universitty of Cologne, Germany

J. J. Rozental
josrozen@netmedia.net.il


jjrozental

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