[sdiy] Eu might be banning Vactrols and LDRs??

[richarnt]

Ian Fritz wrote:
> At 10:39 AM 9/9/2009, David G. Dixon wrote:
>
>> Yes, but sulfides are amenable to oxidative
>
> So you are saying that CdS cells oxidize?  I did not know that.  :-)
>
>
>>  Cadmium contamination is a nasty proposition, as it can cause 
>> serious birth defects.
>> However, there are cheap and effective ways to dispose of it.  It just
>> requires a little coordination and forethought.
>
> Cd plating is all around you.
> http://www.thomasnet.com/products/cadmium-plating-61520300-1.html
>
> Ian
Ian, you need to refresh your basic chemistry. There is a difference 
between atoms in their STP ground state (as Cd metal, Na metal, or 
chlorine gas for example) and their various other states as ions, 
radicals, part of a covalent bonding or whatever other state that is 
relevant in a given substance. David is talking about Cd2+ ions which 
can replace more common metal ions (typically Fe2+ as far as I can 
recall) in water seeping through soil, this then enter plant life, 
aggregates through the food chain and severely mess up biochemistry near 
the top of the chain (that would be us). Cd metal is fairly harmless, 
but when it ends up as waste at the dump it will tend to oxidize and 
become Cd2+.

The constituents of NaCl are Na+ and Cl-. When dissolved in water, you 
get complexes of water molecules and these ions, and they are very 
inert. You need to add energy to get the highly reactive and dangerous 
neutral sodium metal and chlorine gas (you can do that by melting the 
salt and do electrolysis of the melt in an inert atmosphere...not 
recommended for DIY). But roughly two tablespoons of table salt will 
kill you if ingested as the salt will dissolve, enter the blood stream 
and suck the water out of the cells in your body by osmosis. That is 
however not dangerous enough to be labelled toxic. And usually you will 
vomit before the salt is dissolved, the body has some tricks up its sleeve.

Richard