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Author Topic: Radioactive Material - How dangerous?  (Read 7615 times)

Offline chris_s

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Radioactive Material - How dangerous?
« on: 16/09/2011 06:33:41 »
I'd appreciate some feedback. Here is the situation:
  • We have been dealing in some items that are like jewelry. We have recently discovered that these have a significant CPM count (4500+)
  • These are a good selling item so we don't want to stop selling them unless we are convinced that they are unsafe. Assume that these aren't available from any other source so it is probably a matter of continuing to sell the existing ones or stop selling them entirely.
  • My understanding is that there is Alpha and Beta radiation being emitted. I don't know exactly how much there is of each one (we just have a single reading) or if there is any gamma.
  • I've done some research and what that seems to be saying is that the Alpha radiation is relatively harmless in the open air as it quickly turns into Helium and it won't penetrate the skin. If you have a cut in the skin or you ingest some of it (which could happen with a child or a pet) then it could be very dangerous.
  • The Beta radiation can penetrate the skin so it is always going to be a risk. As mentioned previously, we don't know how much Beta is being given off (or even how to determine that).

From what I can understand, a reading of 4500 CPM is significantly above what would normally be considered a safe level. Obviously, what really matters is how much you absorb but if this is being worn close to the body for many hours of the day then I presume that the amount absorbed could be significant as well.

Is my understanding so far correct? If we could get similar products that have a lower CPM level, what level would be considered safe? What negative affects (if any) could be expected from wearing Jewelry with a CPM count of 4500?



 

Offline Bored chemist

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Radioactive Material - How dangerous?
« Reply #1 on: 16/09/2011 06:51:17 »
What are the items made of?
 

Offline chris_s

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Radioactive Material - How dangerous?
« Reply #2 on: 16/09/2011 07:04:30 »
They are made of volcanic rock. I don't know the actual mineral composition.
 

Offline CliffordK

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Radioactive Material - How dangerous?
« Reply #3 on: 16/09/2011 07:49:45 »
If I was you, I would pull the item off of the shelves immediately, until you find out more information.

My guess is that you are picking up a significant amount of gamma counts, as 4,500 CPM would be very high activity for either alpha or beta.  So it is like an X-Ray striking you all the time.  But, this needs much better definition.

And, you should figure out what you have, and also consider a recall of all the items that you've already sold. 

Consider this.
Jewelery is either worn...  or sits in a box all the time.  What if you sell a woman her "favorite" necklace/pendant.  And she wears this pendant 12 hrs a day for 30 years. 

Then, at age 50, she develops breast cancer, and also discovers that her necklace was radioactive.

About 1:8 women have a lifetime risk of developing breast cancer.  But, you sold her the radioactive necklace.  Such a case will go to court.  The jury won't hear the average risk...  they will hear about the radioactive necklace, and that you knew about it, and they will go for a pound of flesh from you, and everyone associated with the radioactive jewelery.

It is possible you have found a new ore.  And it will be more valuable as an ore than as trinkets.;

As far as radioactive materials, you almost always end up with a mix since often one radioactive element decays into a different radioactive material.  If Radon is in the decay chain, it could even emit a radioactive gas.

 

Offline chris_s

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Radioactive Material - How dangerous?
« Reply #4 on: 16/09/2011 15:06:50 »
Thanks for the response. At the moment, we have frozen any shipments (this is all done through the internet). What you say makes sense. It may seem like beating a half-dead horse but my son is the principal person involved and he has put a lot of work into this piece of the business so he is somewhat reluctant to let go. It would be an even bigger financial hurdle for him to actually recall ones that have already gone out. Do you have a good reference that I could give him that shows the kind of impact that you could get from radioactive materials at different cpm levels (and length of exposure)? I have the impression that the 'normal' background level is between 100 and 300 cpm and that this is also treated as the 'safe' level. Is that understanding correct?
 

Offline techmind

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Radioactive Material - How dangerous?
« Reply #5 on: 19/09/2011 23:09:13 »
CPM (counts per minute) is an inexact and poorly defined measure of radiation. We'd normally use Sieverts to measure dosage (on a scale closely-tied to human danger).

That said, if CPM is regarded as a reading from a typical Geiger tube type counter at close proximity, then 10~15 CPM is typical background in my part of the world. You might get to something like double to triple that in a granite area without worrying too much.


Anything up at 4500 CPM sounds seriously scary.

I have previously come across stories of abandoned medical radiation therapy equipment containing dangerous sources being improperly 'scrapped' and the highly dangerous gemstone-like materials being discovered and taken home / split up / sold because they look pretty - but they caused serious harm.

If you've got a stash of this stuff, put it well away from people (eg at the bottom of the garden, but away from boundary fences). Surround it with lead bricks or at least put it inside behind an inch or two of iron/steel and get the experts in.


Where did you get this stuff from?  (be a bit general if you like)
And how did its radioactivity come to your attention?
« Last Edit: 19/09/2011 23:12:16 by techmind »
 

Offline techmind

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Radioactive Material - How dangerous?
« Reply #6 on: 20/09/2011 00:08:16 »
I was thinking of the Goiânia accident:

http://en.wikipedia.org/wiki/Goi%C3%A2nia_accident

Quote
Theft of the source
On 13 September 1987, the security guard in charge of daytime security, Voudireinão da Silva, did not show up to work, using a sick day to attend a cinema screening of Herbie Goes Bananas with his family.[7] That same day, scavengers Roberto dos Santos Alves and Wagner Mota Pereira entered the partially demolished facility, found the teletherapy unit, which they thought might have some scrap value, placed it in a wheelbarrow and took it to Alves' home,[8] about 0.6 km north of the clinic. There, they partly dismantled the equipment, taking the billiard ball-sized caesium capsule out of the protective rotating head. The gamma radiation emitted by the capsule's iridium window nauseated the men and within a day or so, the two men became ill, experiencing vomiting, diarrhea and dizziness. The clinic's diagnosis was that the men were suffering an allergic reaction caused by eating bad food.[1] The two continued their efforts to dismantle the unit, eventually rupturing the source capsule and exposing the radioactive material. The exposure eventually caused localized burns to their bodies and one later had to have an arm amputated.

A few days later one man broke open the iridium window which allowed him to see the caesium chloride emitting a deep blue light.

The exact mechanism by which the light was generated was not known at the time the IAEA report was written. The light is thought to be either fluorescence or Cherenkov radiation associated with the absorption of moisture by the source; similar blue light was observed in 1988 at Oak Ridge National Laboratory during the disencapsulation of a 137Cs source. The man scooped out some of the radioactive caesium and tried to light it, thinking it was gunpowder, and eventually gave up.

The source is sold and dismantled
On September 18 Roberto dos Santos Alves and Wagner Mota Pereira sold the items to a nearby scrapyard. That night the owner, Devair Alves Ferreira, went in the garage and saw the blue glow from the caesium capsule. Over the next three days he invited friends and family to view the strange glowing substance. Ferreira intended to make a ring for his wife, Gabriela Maria Ferreira, out of the material.

Several people who visited the home came into contact with the dust and spread it around the local neighborhood and to other towns nearby. Ferreira's ownership led to many people becoming contaminated. A brother of the scrapyard owner used the dust to paint a blue cross on his abdomen. He also contaminated the animals at his farm, several of which died. At this scrapyard, a friend of Ferreira's (given as EF1 in the IAEA report) hammered open the lead casing. On 25 September 1987, Devair Alves Ferreira sold the scrap metal to another scrapyard. He survived the incident.


Quote
Health outcomes
About 130,000 people overwhelmed hospitals. Of those, 250 people, some with radioactive residue still on their skin, were found, through the use of Geiger counters, to be contaminated. Eventually, 20 people showed signs of radiation sickness and required treatment.

Ages in years are given, with dosages listed in Gy, or Gray.

Fatalities
Leide das Neves Ferreira, aged 6 (6.0 Gy, 600 REM), was the daughter of Ivo Ferreira. Initially, when an international team arrived to treat her, she was confined to an isolated room in the hospital because the hospital staff were afraid to go near her. She gradually developed swelling in the upper body, hair loss, kidney and lung damage, and internal bleeding. She died on October 23, 1987, of "septicemia and generalized infection" at the Marcilio Dias Navy Hospital, in Rio de Janeiro, as a result of the contamination. She was buried in a common cemetery in Goiania, in a special fiberglass coffin lined with lead to prevent the spread of radiation. There was a riot in the cemetery, where over 2,000 people armed with stones and bricks tried to prevent her burial.
Gabriela Maria Ferreira, aged 38 (5.7 Gy, 550 REM), wife of junkyard owner Devair Ferreira, became sick about three days after coming into contact with the substance. Her condition worsened and she developed internal bleeding, especially in the limbs, eyes, and digestive tract, and suffered from hair loss. She died 23 October 1987, about a month after exposure.
Israel Baptista dos Santos, aged 22 (4.5 Gy, 450 REM), was an employee of Devair Ferreira who worked on the radioactive source primarily to extract the lead. He developed serious respiratory and lymphatic complications, was eventually admitted to hospital, and died 6 days later on 27 October 1987.
Admilson Alves de Souza, aged 18 (5.3 Gy, 500 REM), was also an employee of Devair Ferreira who worked on the radioactive source. He developed lung damage, internal bleeding, and heart damage, and died 18 October 1987.



Be very wary of strange stones from dubious sources that glow in the dark!
« Last Edit: 20/09/2011 00:11:38 by techmind »
 

Offline Bored chemist

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Radioactive Material - How dangerous?
« Reply #7 on: 20/09/2011 18:59:42 »
That source was something like 4,400,000,000,000,000 counts per minute.
The difference may be significant.
Most rocks are essentially harmless from a radiological point of view. We evolved to cope with that sort of thing.
Having said that, I'd not try to sell them as jewellery.
On the other hand, there's nothing wrong with selling rocks on eBay. If people want to check that their Geiger counter is working, rocks are about the only legal check source they can buy.
 

Offline techmind

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Radioactive Material - How dangerous?
« Reply #8 on: 20/09/2011 19:10:04 »
I agree we simply don't know how active the original poster's source is.
They don't even say whether they get 4500cpm off a large lump or off a single gemstone/jewellery-sized piece.
We also don't know what sort of Geiger counter the OP was using - there's a possibility that it's saturating at 4500cpm - you could test by moving the detector a few inches away and make sure the counts drop appreciably...

I've no idea how active likely natural sources might be...
 

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Radioactive Material - How dangerous?
« Reply #8 on: 20/09/2011 19:10:04 »

 

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