Addendum: Depleted
Uranium Oxide, AKA Yellowcake, and Safety
Questions have arisen regarding
the safety and wisdom of using uranium as a glaze ingredient. I do not endorse
the use of uranium as a glaze ingredient in any way.
According to Ruben
Cortez, Radiation Safety Officer, Environmental and Consumer Safety Section, Texas
Department of State Health Services, depleted uranium oxide is not a great radiation
hazard - in fact he showed me a sample of depleted uranium oxide in a glass amphora
that he keeps in his office. Depleted uranium oxide makes up a very small percentage
of my uranium glaze recipe. After firing, this small amount of depleted uranium
is "trapped" in the vitreous glass glaze. I use my uranium glaze only on decorative
vases, not on work that is likely to be used for serving food. The word "URANIUM"
is clearly incised onto the bottoms of all work that I make which contains depleted
uranium oxide. Uranium is ubiquitous, we are surrounded by minute quantities of
it which we breathe in and ingest daily, and which we eliminate from our bodies
vie our feces and urine daily.
Here is a short list of links
to websites that address the issue of safety and the use of depleted uranium oxide,
along with a few, brief, relevant excerpts:
http://en.wikipedia.org/wiki/Uranium
Uranium
is commonly found in very small amounts in rocks, soil, water, plants, and animals
(including humans). Depleted uranium is used in helicopters and airplanes as counterweights
on certain wing parts. Some lighting fixtures utilize uranium. A person can be
exposed to uranium by inhaling dust in air, or ingesting water and food. The general
population is exposed to uranium primarily through food and water; the average
daily intake of uranium from food ranges from 0.07 to 1.1 micrograms per day.
http://encyclopedia.lockergnome.com/s/b/Depleted_uranium
Depleted
uranium is also used in a number of civilian applications, generally where a high
density weight is needed. Such applications include sailboat keels, as counterweights
and sinker bars in oil drills, gyroscope rotors, and in other places where there
is a need to place a weight that occupies as little space as possible. Aircraft
may also contain depleted uranium counterweights (a Boeing 747 may contain 400-1,500kg).
However there is some controversy about its use in this application because of
concern about the uranium entering the environment should the aircraft crash,
particularly as the metal is pyrophoric. This was highlighted by the collision
of two Boeing 747s at Tenerife Airport in 1977 when the resulting fire consumed
3000kg of the material. Consequently its use has been phased out in many newer
aircraft, for example both Boeing and McDonnell-Douglas discontinued using DU
counterweights in the 1980s. An unexpected application is in Formula 1 racing
cars. The rules state a minimum weight of 600kg but builders strive to get the
weight as low as possible and then bring it up to the 600kg mark by placing depleted
uranium where needed to achieve a better balance.
http://deploymentlink.osd.mil/news/dec04/news_20041206_001.shtml
Depleted
uranium is 40 percent less radioactive than the natural uranium that we all eat,
drink, and breathe daily.
http://www.deploymentlink.osd.mil/du_library/what.shtml
Each of us ingests and inhales natural uranium every day from our air, water,
food, and soil. The amount varies depending on the amount found where you live,
and where the food you eat and the water you drink are produced. Consequently,
each of us has some uranium in our body, and we eliminate some in our urine every
day.
Uranium in our Bodies
Source.................................................Amount
(micrograms*)
Average Daily Intake: Liquid.................2.1
Average Daily
Intake: Food (U.S.)........0.9 - 1.5
Average Daily Intake: Inhalation.............0.0010
- 0.010
Average Uranium (total) in the body.......2 - 62
*Note: 1 microgram
= 0.000000035 ounces
http://www.deploymentlink.osd.mil/du_library/health.shtml
RAND, 1999. "(N)o evidence is documented in the literature of cancer or any other
negative health effect related to the radiation received from exposure to natural
uranium, whether inhaled or ingested, even at very high doses." Department of
Health and Human Services, Agency for Toxic Substances and Disease Registry (ATSDR)
in 1999 Toxicological Profile for Uranium. "No human cancer of any type has ever
been seen as a result of exposure to natural or depleted uranium."
http://www.ceramic-materials.com/cermat/education/172.html
"URANIUM and CERAMICS" by Edouard Bastarache.
http://www.glass.co.nz/uranium.htm
"Uranium, fluorescent and Vaseline Glass." Boyd Glass and Fenton Art Glass are
two USA companies that produce uranium glass items today. Tests conducted by Jay
Glickman (reported in his book "Yellow-Green Vaseline: A Guide to the Magic Glass)
and separate tests by Frank Fenton, of Fenton Glass, have shown that the radiation
levels from even large quantities of uranium glass at close quarters are no more
harmful than those associated with television sets or microwave ovens.
http://www.wise-uranium.org/dviss.html#PHILMORGAN
Crystalline glaze artist Phil Morgan's application to aquire depleted uranium
oxide.
There are plenty of "scare" sites dealing with depleted
uranium oxide on the World Wide Web. Please educate yourself. Remember that radiation
is not harmful per se. There are different types of radiation. Radiation treatments
are used to treat some types of cancer and have saved lives. Let me stress that
I do not endorse the use of uranium as a glaze ingredient in any way. Depleted
uranium is a heavy metal, and is highly toxic when ingested. People working with
uranium should educate themselves to the dangers involved. Ceramists using uranium
should, at the very least, exercise the same precautions that they use when handling
lead, barium or manganese, and should wear respirators and hand protection at
all times. Uranium-containing glazes should never be used on functional ware.
This is what all of the above vases look like lined up side-by-side. From left
to right, numbers 1 through
6.
