muso wrote on Oct 7^th, 2010 at 8:42am:


How much waste is "less waste", and how toxic is it, and how long does it remain so?

I still hold massive concerns over Nuclear waste, and until we have a waste product that will not remain deadly for periods exponentially longer than any civilisation has ever lasted, then I will continue to hold such concerns.

Mozz.
Quote:


Trust me - I used to work for the government.
Thorium is very safe.
You could have a reactor at the end of your street & not have to worry at all.

pjb05 wrote on Oct 7^th, 2010 at 5:47pm:


That's what I thought I said - I was talking in terms of waste.

The green glass probably contains mostly Uranium 238. It's the most abundant form (about 98%) of Uranium found naturally.

It has a half life the age of the Solar System (4.5 billion years) but it's an alpha emitter which means that you can hold a lump of U-238 wearing a pair of rubber gloves.



Alpha emitters are the worst when it comes to ingested or inhaled dust because Alpha particles cause about 100 times more damage to the body cells, compared to gamma rays, which penetrate the entire body.  

It fluoresces green under UV light. The old watch dials that used to glow green contained some Radium.

Yes, you can encapsulate the waste in borosilicate glass.

Pjb05,
Quote:


When I was a young Uni student I took a watch
( an old present from my grandfather ) & presented it to the
lecturer when he was measuring radioactivity with
a geiger counter of some samples.
My watch was more radioactive than his samples.
The marks for hours & the hands would glow in the dark
as they were painted with flourescent paint mixed with
some sort of radioactive ore. ( Radium? )

You can't get watches like that now - but  - maybe they are dangerous?

Bobby. wrote on Oct 10^th, 2010 at 9:01pm:


Radium is highly radioactive. Marie Curie's desk and papers are still radioactive and can only be handled with special precautions. She used to keep samples in her desk and open the drawers and admire the pretty glow they gave off. As the discoverer of radium she was given a pendant containing some radium. She died from lukemia brought on by overeposure to radiation.
 
Yes radium was used on watch dials but id not regarded as a health hazard for the wearer:

http://www.arpansa.gov.au/radiationprotection/factsheets/is_radium.cfm

Radium Paint in Wrist Watches

Paint containing small quantities of radium-226 has been used since the early 1920’s on the hands and numerals of wrist watches. Following the discovery of radium by Pierre and Marie Curie in the early 20th century, it was quickly realised that the luminescent properties of radium made it useful on watch and clock faces, as it made them easy to read in the dark. Paint containing small quantities of radium-226 has been used since the early 1920’s on the hands and numerals of wrist watches.

Although the scientific literature contains many stories about the high rate of cancer among the women employed as dial painters, the radiation risk associated with wearing a standard wrist watch is extremely small.

Radium emits alpha radiation and gamma radiation. The alpha radiation carries most of the energy, but is only hazardous when taken into the body by inhalation or ingestion, or through open wounds. Gamma radiation is more of an external hazard, but there is only a small amount of radium on the face of a typical wrist watch, and the back of the watch (next to the skin) is protected by a metal or plastic case.

The problem with the dial painters occurred because watch faces are very small, and the dial painters had the habit of licking the tips of their brushes to make a fine point, so that the paint would go where it was wanted. As a result of this practice, which was carried out for a number of years, most of the cancers suffered by the dial painters were cancers of the jaw, mouth and throat.

Other non-radioactive substances are now used in modern watches to make them visible in the dark. The wearing of older wrist watches that do contain luminescent radium paint is not regarded as any form of health hazard.