On Mon, Apr 10, 2006 at 10:25:50AM -0500, Matt Pobursky wrote:
> "Cleaning-product manufacturer Kleinmann GmbH, which packages and sells the 
> sprays, quickly withdrew aerosol formulations that also contain a propellant 
> and warned against their further use. The company has sold the products in 
> pump bottles for more than two years and has had no reports of problems. The 
> sprays are designed for treating glass and ceramic surfaces to make them 
> water- and dirt-repellant for easier cleaning."
> 
> It sounds to me like it's a problem with the delivery system rather than 
> what's being delivered...

Well... Yes, and no. Take pottery clay for example. If you "deliver" it
to your body in wet form, and say, eat it, nothing bad is going to
happen to you. Maybe a little stomach upset. You can get it all over
your skin, no problem. But dry it and let it get into the air as dust
and in extreme cases, you can die after *one* exposure due to the silica
content. It's the same stuff, but different delivery. It used to be
quiet common for ceramics workers to have serious lung problems after a
few years. I'm sure if you made up aerosol cans of standard pottery clay
the silica would suspend quiet nicely and do you some serious damage.
Heck, I've heard of a few examples where silica containing clays were
accidentally mixed into dust meant to be used in things like movies to
generate dust clouds. The actors were seriously injured for life or
killed.

It's not the delivery mechanism per say, it's that some materials are
*way* more toxic if they are delivered by different mechanisms. And
unfortunately, our lungs are an example of this. Particles of just the
right size get trapped in your aveola and cut the cells up, just like
aspestos does.

Or for another example... Try drinking some murcury, you'll probably be
just fine. Now try dropping some on a hotplate and breathing in the
fumes. You'll die in a few days to a few months.

Or back to ceramics again, I like to use a particular type of black clay
in my art work. It's black (well dark brown) due to the addition of
maganese and some magnesium. The particular form used happens to be a
nurotoxin. Fortunately, it very poorly absorbed by the skin and
diegestive system. But if I let it turn to dust and beath it in... The
lungs absorb it just fine. Of course, if that's happening, I'm also
breathing in silica dust, and will die from that too, but aparently the
neurotoxin effect happens in about a third of the time. So if I'm not
carefull, I can end up having seizures due to nerve damage for a few
years, then finally die of lung failure, wonderfull!

-- 
pete@petertodd.ca http://www.petertodd.ca
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