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'TUDE
May 13, 2005, 21:33
Anybody familiar with radiation exposure?

Forteen years ago, I was exposed on two different occassions (not my fault) to radiation and had to undergo thyroid scans for 3 months afterward.
Once was radioactive iodine and the last was a radioactive density probe that measured a considerble amount.

My question is, all these years later, would there be any chance of "after effects" even knowing my thyroid scans were clean previously? Is there a newer or better test now days?

cm
May 14, 2005, 02:25
hi... do you know what the radioactive density probe was made of? were the radiation exposures external to your body, or did you ingest/inhale the substances?

don't know a lot about radiation, but know a little about thyroids. the thyroid makes hormones that control things in your metabolism, the level of hormones in your body affects how fast or slow your metabolism is.

radioactive iodine is used to treat a condition called hyperthyroidism. it gets taken up in the thyroid, and basically ablates it. what happens then is you become hypothyroid (have low thyroid hormone levels), and need to take thyroid hormones there after to maintain your metabolism.

symptoms of hypothyroidism are cold intolerance, fatigue or weakness all the time, slow heart rate, weight gain.

a few simple blood test can determine if your thyroid appears to be working properly, with further studies as needed.

Firestarter
May 14, 2005, 07:47
In a nutshell no.

You will not have any long term or even short term effects from an I-123 uptake study. Iodine 123 has a physical half life of 13 hrs but the biological T1/2 will be much less. You either received a 100 uCi or a 200 uCi pill which is pretty minimal. Did they follow up with a shot later that day? This would be a TC-99m dose that will also show up in your thyroid as a secondary test for comparison although this dose would show more structure than function.

I-123 also has a low energy primarily gamma emmission.

I-131 which has ben mentioned here before is some nastier stuff and has a physical T1/2 of around 8 days. It is a great thyroid ablation agent as an alternative to surgery. Unlike surgery it can attack and ablate ANY cancerous thyroid tissue in the body. (thyroid cells that migrate). Doses for this can range from about 30 mCi to a whopping 200 mCi per dose. Unlike I-123 it is potentially harmful to everyone around you if you are sent home and special precautions have to be made. It is also volatile in nature especially around h20 and will turn into a gas. Special handling is required in the lab when compounding this stuff. It is nuclear reactor waste from Canada. Nice huh?

This being said it is still a safe treatment for it's patients with the benefits outwaying the risk associated with it.

Nuclear medicine is a pretty safe study.

The principles of radiation safety are summed up in a term called ALARA or as low as reasonably acheivable. The three main principles of RAM safety are time exposure, distance from, and sheilding.

I don't know about the density probe. Never have heard of one being used. Cesium 137 is usually used for density measurements but we are talking industrial applications. I always suspected you for some snake honing android!

Are you sure it wasn't a bioassy probe? Or was it the probe that they used to measure your uptake? I would bet that it was the latter now that I think about it.

No worry's my friend. I am a nuclear pharmacy technician and an authorized user at our pharmacy. Authorized user does not mean that I "use", it means that others may only work with the stuff if I am present.

Firestarter
May 14, 2005, 07:55
After re-reading your post I am still trying to figure out what you meant by exposed. Were you exposed to an external source accidently, and this is what warranted the subsequent studies?

Or are the studies themselves what you are referring to?

Was the density probe a study or was it an accidental exposure?

The density probe was probably Cesium and yes industrial probes are very hot.

How close and for how long were you around it? The Iodine. What kind was it? Do you know? How long were you exposed to it and what form was it in?

Where in the hell were you to get exposed to the Iodine?

'TUDE
May 14, 2005, 10:10
Originally posted by Firestarter
After re-reading your post I am still trying to figure out what you meant by exposed. Were you exposed to an external source accidently, and this is what warranted the subsequent studies?

Or are the studies themselves what you are referring to?

Was the density probe a study or was it an accidental exposure?

The density probe was probably Cesium and yes industrial probes are very hot.

How close and for how long were you around it? The Iodine. What kind was it? Do you know? How long were you exposed to it and what form was it in?

Where in the hell were you to get exposed to the Iodine?

This was all work-related while in the oil field. The iodine exposure was from a column of water treated with the iodine in the wellhead itself awaiting to be pumped downhole for formation study. The seal that prevented fluid from exiting the well failed and showered me from head to toe. Not sure what type of iodine it was but my clothing had to be destroyed and I was scanned right afterward following showers.

The probe is a downhole tool as well. An operator who was in charge of the probe didn't secure it properly in its lead-lined container and it rolled out, finding rest under my seat. Exposure time was somewhere between 1-2 hours.

I didn't work with this company but for a month due to obvious safety issues. I do know that it was a joke around the shop of who had the "hottest" truck. No place on the exterior of our trucks was clean as meters would register varying amounts of radiation.

ANON
May 14, 2005, 10:30
"An operator who was in charge of the probe didn't secure it properly in its lead-lined container and it rolled out, finding rest under my seat. Exposure time was somewhere between 1-2 hours."

That could be an OSHA violation.

Firestarter
May 14, 2005, 12:28
Originally posted by ANON
"An operator who was in charge of the probe didn't secure it properly in its lead-lined container and it rolled out, finding rest under my seat. Exposure time was somewhere between 1-2 hours."

That could be an OSHA violation.

Not to mention an NRC violation, a State health dept. violation, and probably a DOT violation as well.

Glad you quit Faltitude. Evil Ted could tell you a bit about exposure as well since he works at a reactor. I am somewhat familiar with the type of sealed source that you are describing.

It was probably a relatively high energy CS-137 source with an energy of 662 Kev (1Kev=onethousand electron volts) and is an ionizing source of radiation.

You say the source wasn't secured properly. Was it still in the container or out of it's lead-lined container when it rolled under your seat?

This is an instance that should have been reported.