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Author Topic: Toxicity of metallic lead to touch?  (Read 2196 times)

Offline valeg96

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Toxicity of metallic lead to touch?
« on: 27/03/2014 17:53:25 »
So, I keep hearing people saying how touching metallic lead poisons your body. I am aware that lead compounds are (neuro)toxic, for example Pb3O4. Is metallic lead toxic to touch? It seems pretty exaggerated to me, it has always been used for water pipes (etymology of plumber) and other common items. So yeah, what do you know?


 

Offline Bored chemist

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Re: Toxicity of metallic lead to touch?
« Reply #1 on: 27/03/2014 20:36:46 »
It's a difficult question.
I doubt that metallic lead could ever get through the skin in large enough quantities to do any harm.
However, lead is very soft. if you handle it the metal rubs off and stains your skin black.
If you then transfer that finely powdered lead to your mouth (or even eyes or nose) it will get into the body and may cause problems.
The other thing to remember is that lead is a cumulative poison., It tends to build up in the body so, even if it doesn't harm you at first, it could build up  enough in the body to cause harm later.

There are some lead compounds that definitely pass through the skin and are very toxic that way.
http://en.wikipedia.org/wiki/Tetraethyllead

Also, lead was used in plumbing- and that was a bad idea. Most of it is now being removed.
 

Offline CliffordK

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Re: Toxicity of metallic lead to touch?
« Reply #2 on: 28/03/2014 05:14:05 »
Casual contact with lead or lead solder shouldn't be a problem.  I would not wear something like a lead or pewter bracelet. 

NOTE, Pencil Lead is not actually Lead!!!

The concern with lead poisoning is often with children and school kids, although I suppose it could also affect adults. 

Lead in the drain pipes is not typically a problem, at least not for the homeowners (perhaps it is for water treatment/discharge/sludge disposal).  Lead in the inbound pipes is considered a problem.  For quite some time, lead solder has not been legal for use in the USA for joining copper pipes, although it may still be in use with some electronics and copper/brass radiators.

There is also a risk of antique copper vessels such as teapots or samovars (samowars) having parts joined with lead.  And, of course, one would discourage using pewter for food.

Lead solders typically are duller in appearance than silver and non-lead solders.
 

Offline CliffordK

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Re: Toxicity of metallic lead to touch?
« Reply #3 on: 28/03/2014 05:16:56 »
I have wondered whether it would be safe enough to use copper pots with lead joints after applying a HEAVY tin plate internally.
 

Offline valeg96

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Re: Toxicity of metallic lead to touch?
« Reply #4 on: 28/03/2014 13:13:07 »
I've melted quite some tiny pieces of metal in one round, coin-like block so a couple of people asked me to show them the result and the crystal-like shape on the top, and they all said I should be wearing gloves to handle it  because it's poisonous. I'm not using it as a necklace or anything, and I guess occasional handling isn't a problem.
 

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Re: Toxicity of metallic lead to touch?
« Reply #4 on: 28/03/2014 13:13:07 »

 

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