FWD: Query from OccMed list

[ccc@pp.pdx.edu (Chuck Cooper)]

Forwarded message:
> From sdesilva@aeha1.apgea.army.mil Thu Sep  5 13:50:55 1996
> Message-Id: <9609051943.AA04973@aehafs1.apgea.army.mil>
> Date: Thu, 05 Sep 96 15:59:07 -0700
> From: "Shirin R. de Silva, MD, MPH" <sdesilva@aeha1.apgea.army.mil>
> Organization: USA-CHPPM
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> This is a second post to your letter.  In my first post, I assumed that 
> all or almost all the exposure involved internal ingestion of Iodine-131 
> and Ce-137 through poor workplace hygiene, and that there was essentially 
> no internal exposure to Iridium.  I now realize that is in doubt.    
> 
> Field radiography using Iridium-192 depends on gamma radiation, and the 
> components are usually well shielded.  However, if the technique was as 
> sloppy as you describe, the workers may sometimes have left the iridium 
> source outside the shielding tube.  This can result in severe radiation 
> exposure.  Has your patient ever had radiation burns?  How about other 
> people at his workplace?  
> 
> Iridium-192 has an annual intake limit of 80 _microcuries_ by inhalation. 
> If the patient's exposure to iridium-192 of 10-20 mcuries means internal 
> exposure and is in _millicuries_, then your patient is over his annual 
> limits.  However, your patient shouldn't have been able to inhale or 
> ingest the iridium used in field radiography.  How was exposure to the 
> various isotopes determined?  Are we talking about internal exposure 
> received by the patient, or about the theoretical radioactivity of the 
> material?  If we are talking theoretical radioactivity, then you need to 
> look at the film badge, personal dosimetry information in order to get a 
> handle on your patient's exposure.
> 
> If your worker uses radioactive iridium he is a radiation worker and you 
> use that standard.  
> 
> The reference I mentioned in my previous post also deals with inhalation 
> exposure assessment, if the manufacturer is unable to give you any help.
> 
> I am not familiar with Ammerisium.  Are you sure about the spelling?  I 
> would check with a health physicist, your local Nuclear Medicine 
> specialist, and the U.S. Nuclear Regulatory Commision about that one.
> 
> ----------------------------------------------------------------------
> 
> 
> 
> From: CJMARTIN@PHS.Med.UAlberta.CA
> Organization:  Public Health Sciences, U Alberta
> To: occ-env-med-l@list.mc.duke.edu
> Date:          Wed, 4 Sep 1996 13:16:47 MDT
> Subject: OEM: Carcinoid tumour of thymus and radioisotope exposure
> Priority: normal
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> 
>     Here is case that we would appreciate your comments on:
>      
>         We have just seen a 46 year old man who was employed from 
> 1969 to 1978 as an oilfield cased-hole logging engineer.  Essentially 
> his work involved the underground injection of various radioactive 
> isotopes to obtain information on the best method to extract oil and 
> natural gas reserves.  He was exposed to the following agents:
> 
> Iridium-192          10-20 mcuries       (seldom used)
> 
> Ammerisium-berylium    3-5 curies        (used everytime a well was 
>                                          logged, approximately 150-
>                                          200 times/yr)
>                                          
> Iodine-131             20 mcuries         (In liquid form, 100 
>  
> Cesium-137             3 curies          (used 4-5 times/year)
> 
> 
>     He describes the workers attitude towards radioactive hazards as 
> "cavalier".  They used no protection whatsoever.  Isotopes would 
> spill on clothing, blow into their faces etc.  They would store them 
> in the trucks to prevent freezing.  When the patient took a safety 
> course on radioisotopes, he recognized the danger and quit this line 
> of work!
> 
>     He began to experience sharp retrosternal chest pain in 1981.  
> After being treated for everything you could possibly imagine, he 
> eventually had an open thoracotomy in 1989 at which time the tumour 
> was found and a tissue sample was taken.  He has had courses of 
> radiotherapy and chemotherapy, his lesion is apparently unresectable. 
> There has been impingement on his SVC and a stent has been inserted. 
> He is aware that the cancer is terminal but, understandably, no one 
> has given him a time frame. He is being followed with CT Scans every 
> 6 months.
> 
>     We have been asked to comment on causation.
> 
>     He says numerous other co-workers have had various types of 
> malignancy - 2 cases of leukemia, plus bowel, prostate, bladder, 
> testicle.  Apparently several have had thyroid abnormalities but the 
> patient is unsure exactly what these are. 
> 
>     We are in the process of:
>     - Alerting our Dept of Labour to the situation
>     - Obtaining all his records
>     - Searching the literature
>     
>     Any insight or help with this case the group could provide would 
> be most welcome.
> 
> 
> Christopher Martin
> Resident
> Occupational Health Program
> University of Alberta
> Edmonton, Alberta
> 
> 
> 
>