Re: Sm-153

[Franz Schoenhofer <schoenho@via.at>]

At 16:35 20.01.2000 -0600, you wrote:
>>I have a client who uses Sm-153 Quadramet and cannot get the vials to
>decay to background so that they can be disposed of. The half life of
>Sm-153 is 46.3 hours so the vials should be ready to toss after 20 days,
>but when they were surveyed 11 months after being placed into storage they
>still produced an exposure rate considerably higher than background.
>>
>>This has happened with all of the Sm-153 vials, and not just one, and with
>several survey meters.  Has anyone else heard of this?  Is it possibly a
>case of long-lived contaminants?  

Not being an expert on this topic I would believe that this is the only
explanation.

And if so, what and how much?  I have
>tried contacting DuPont and Berlex by phone and e-mail but have not gotten
>any help yet.

I ask very cautiously whether there are any regulations in the USA with
regard to isotopical purity of radiopharmaceuticals. If they exist - and I
believe that in a civilized country like the USA they should exist - the
companies supplying these radiopharmaceuticals should be responsible for
any long lived impurities which might cause additional exposure to the
patients. Have you checked the additional dose to the patients? Is it
beyond acceptable limits?

Best regards,

Franz





>>
>>M.E. Jafari, M.S.,DABR
>>Western Radiological Physics, Inc.
>>westrad@cyberhighway.net
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Franz Schoenhofer
Habicherg. 31/7
A-1160 Vienna
Austria
Tel.: +43-1-495 53 08
Fax.: same number
mobile phone: +43-664-338 0 333
e-mail: schoenho@via.at

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