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

[Ian Fritz]

At 05:15 PM 9/9/2009, richarnt wrote:
>>>  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.

Yeah, I'm just a dumb physicist.  But I've talked to chemists about this 
and they all agree that basing an MSDS on the MSDS's of the separate 
elements doesn't make sense.

>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.

Oh, spare me, please. You missed the whole point.

Ian