I am sure that most people are not aware that some of the consumer products that are present around us contain Radioactive Material/s (RAM) (i.e. Uranium).
I am posting this, not to scare the public but to raise their awareness on what common consumer products contain this RAM. Furthermore, this is to inform them that radiation has many uses in our daily lives.
Take a look at the following images and see if you recognize them are if they are present in your homes.
Check - Up Gum
Check- Up Gum helped fight plaque. As the gum was chewed, tiny granules of zirconium silicate (the third listed ingredient) scraped the teeth clean.
The reason that Check·Up Gum is featured here is that the zirconium silicate contained elevated levels of uranium and thorium (e.g., 100 pCi/g). The amount of zirconium silicate in the gum was such that the uranium concentration is approximately 7 pCi per gram of gum. Since the uranium series is in secular equilibrium, the gum also contains 7 pCi of Ra-226 per gram. As a matter of interest, there have been many situations where this level of radium in soil has required remedial action.
Although Check·Up Gum is no longer produced, zirconium silicate continues to be used in dental pastes and some toothpastes. Nevertheless, consumers can rest assured that the radiation dose is negligible - the radioactive material is bound up in the zirconium silicate and would not be assimilated even if swallowed.
Tape Dispenser
This is a 3M Model C-15 Decor Scotch tape dispenser. It is slightly radioactive due to the thorium-containing monazite sand that was used as ballast. This particular example came from a 55 gallon drum of tape dispensers that the U.S. Army was about to dispose of as radioactive waste.
Jewelries
As a result of an investigation in early 1988 by the Los Angeles County Health Department, various state radiation control programs in the U.S. issued warnings concerning the manufacture and use of jewelry made from old watch parts. These parts often included radioluminescent watch faces and hands. The jewelry, which included, broaches, bracelets, earrings, etc. had become quite popular and because it was easy to produce, the typical manufacturer was a small business operating out of someone's home or apartment. Production is known to have occurred in California, Oregon, Texas and Pennsylvania. The radiation control programs in Tennessee, Texas and possibly some other states invited the public to bring suspect jewelry to their offices to be monitored for radioactivity.
The usual mode of manufacture was to dismantle old watches, clean the parts with some sort of abrasive, polish the pieces, assemble the jewelry, and possibly coat it with an acrylic spray. It seems that there was no awareness on the part of the manufacturers of the potential hazards.
Even though some of the jewelry was worn in direct contact with the skin, and a number of premises were found to be contaminated (e.g., up to 50,000 cpm), there were no reports of injuries to individuals who wore or manufactured the jewelry. Nevertheless, one individual, who had been making such jewelry for six years, was found to have "1/30 of a body burden of radium-226."
Potassium Chloride Water Softener Salt
Hard water contains more minerals, especially calcium and magnesium, that ordinary water. This can lead to the build up of scale in pipes and appliances. A water softener is used to reduce the concentration of these minerals.
In essence, a water softener consists of an ion exchange resin that removes the minerals as the water flows through it. After a while, the resin becomes saturated with these minerals and it no longer functions. At this point, a salt solution is added to the resin. The salt exchanges with the accumulated minerals, and allows them to be washed out of the softener into a drain. This rejuvenates the softener.
A variety of materials can be used as the water softener salt, e.g., sodium chloride (NaCl) or potassium chloride (KCl). In the example shown here, the water softener salt is over 99% potassium chloride.
All potassium contains potassium-40, a naturally occurring beta gamma emitter, and in large enough quantities it is easily detected with a simple survey meter. This bag, for example, could not get through a monitor at a nuclear power plant without setting off an alarm.
Smoke Detectors
The ionization chamber smoke detector was invented in the early 1940s in Switzerland , and introduced into the U.S. in 1951.
The sensitive component of the ICSD is an ionization chamber that is open to the atmosphere (photo below left). A radioactive source inside the chamber emits radiation that ionizes the air in the chamber and makes it conductive.
Ionization chamber smoke detectors almost always use alpha emitters as the source because of the high density of the ionization that they produce.
Most ICSDs sold today use an oxide of americium-241 (Am-241) as the radioactive source. The typical activity for a modern residential ICSD is approximately 1 uCi, while the activity in one used in public and commercial buildings might be as high as 50 uCi. In 1980, the average activity employed in a residential smoke detector was approximately 3 uCi, three time higher than it is today.
Am-241 is an alpha emitter, but it also emits a low energy (59.5 keV) gamma ray. The Am-241 is mixed with gold and incorporated into a composite gold and silver foil sandwich. The source is 3 to 5 mm in diameter, and either crimped or welded into place inside the chamber.
Other nuclides have also been used. NRC records indicate that approximately 124,000 ICSDs were sold between 1971 and 1986 that employed nickel-63 (Ni-63). These units averaged approximately 10 microcuries of Ni-63 each.
Radium-226 (radium sulfate) was the first radioactive source used in smoke detectors. According to NUREG/CP-0001, U.S. producers stopped making Ra-226 containing smoke detectors in 1963 when they switched to Am-241. Nevertheless, according to NCRP 95, it would seem that radium-containing ICSDs continued to be sold in the U.S. at least until 1978. A typical residential smoke detector contained 0.05 uCi of Ra-226, but some contained up to 0.1 uCi. Commercial smoke detectors employed considerably higher activities.
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