Joyce Lee on sat 11 oct 03
When I first began using cadmium (very
carefully), I found this on the net, Paul.
"Almost all cadmium is obtained as a by-product
in the treatment of zinc, copper and lead ores.
It is a soft bluish white metal which is easily
cut with a knife. It is similar in many respects
to zinc. It is a component of some of the lowest
melting alloys............. It was discovered
in 1817. It's used extensively in electroplating.=20
It is also used in many types of solder, for
standard E.M.F. cells, for Ni-Cd batteries and
as a barrier to control nuclear fission.
It forms a number of salts, of which the sulfate is most common; the =
sulfide is used as a yellow pigment. Cadmium and solutions of its =
compounds are toxic. Failure to appreciate the toxic properties of =
cadmium may cause workers to be unwittingly exposed to dangerous fumes. =
Silver solder, for example, which contains cadmium, should be handled =
with care. Serious toxicity problems have been found from long-term =
exposure and work with cadmium plating baths. Exposure to cadmium dust =
should not exceed 0.01 mg/m^3 (8-hour time-weighted average, 40-hour =
week). The ceiling concentration (maximum), for a period of 15 min, =
should not exceed 0.14 mg/m^3. Cadmium oxide fume exposure (8-hour, =
40-hour week) should not exceed 0.05 mg/m^3, and the maximum =
concentration should not exceed 0.05 mg/m^3. These values are presently =
being restudied and recommendations have been made to reduce the =
exposure. In 1927 the International Conference on Weights and Measures =
redefined the meter in terms of the wavelength of the red cadmium =
spectral line (i.e. 1m =3D 1.553,164.13 wavelengths). This definition =
has been changed (see under Krypton). The current price of cadmium is =
about $12/lb. It is available in high purity form."
I have a file with a lot more in it that
also came from the net but it doesn't=20
appear pertinent. It wasn't to me, at
least.
Joyce
In the Mojave
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