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| Joined: | Thu Apr 16th, 2009 |
| Location: | Arctic, Norway |
| Posts: | 5821 |
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..don't worry these are only toxic if you eat them..
Putnam, you don't need to ingest materials for them to have a toxic effect on the organism. The skin and it's pores are an open door on external components if you are in tight and repetitive contact with them. The pores absorb toxines when beeing in long contact with toxic materials. That's how people got skin rashes from components like nickel or chrome placed on cheap jewelry or bracelets...
As an extreme exemple...
That's also how we had people on oil platforms dying of leukemia and other cancers after having them skin repetedly in contact with hydrolic and turbine synthetic oils...
The oil leaked in the gloves, clothes and contaminated them.
To finish with that:
In the old time, we was using lead pipes for drinking water and even lead for the first tinned foods, resulting after long time of exposure, to contaminations or poisoning called "Saturnism"...
Offcourse this is not the case with this bronze containing maximum 7% of lead and who is not ingested: My exemple is just an extreme one to show how simple repetitive contact with some special elements can be dangerous.
Consider also the fact that it's brass, not bronze, who is commonly used on plumbing valves, and should contain under 4% of lead when in contact with drinking water, from what I've been reading.
Exemple: The state of California took it down this year to maximum 0.25% of lead for the brass parts in plumbing for drinking water, based on security reasons.
From what I understood, the only purpose of the lead presence in the bronze or brass, is to make it more easy to be machined as it get tender and don't rip or crack so easily under the cuting, machining...
Again,as I said, ingestion makes you much more exposed than simple long skin contact: No doubt there.
However, my question is: Is there any special reason related to any health normes for that the most used bronze alloy in watch manufacture, is the one who don't contain lead? Or is that only based on the fact that this alloy is harder and more resistant to sratches,dings...?