China is the manufacturing base for almost all of the world's metal costume jewelry components. There are a few beads made in Europe and South America, but almost all cast metal comes from China. This applies whether it was purchased in a dollar store or in a jeweller's. Buying findings from an American supplier changes nothing. He bought them from factories in China.
Around 2005 there were problems with other manufactured items from China containing lead (children's toys etc) and it threw open the whole question of what else it was being used in. Tibetan silver, for example, one of the main alloys used in costume jewelry is a very varied recipe, goes back hundreds of years, and being similar to pewter it certainly did used to contain lead. The quantity, however, was very small, for the simple reason that too much makes the metal soft. That simply doesn't work on jewelry items - they would break.
No legislation was ever put into place in China to actually ban the use of lead, which scared many people in the west. What they forgot however was that China is a market-driven economy - which seems ironic considering its government - because if it doesn't offer what the western importers want, they simply won't buy it. So, wise manufacturers clued in and stopped using lead voluntarily, along with allergens such as nickel, as a sound business decision. As time went by those businesses thrived and many of those still using the "unwanted" metals have simply gone out of business.
The exceptions are those eking out a very precarious living selling ultra-cheap, very poor quality items in bulk to wholesalers and mass retailers. It is therefore actually quite easy to use quality as a guide. If it looks tacky, if it breaks easily, that's the stuff most likely to have been made from toxic metals.
Recent reports of children's jewelry found containing lead and other toxins, notably in Wal-Mart, have again raised the issue, because children may indeed put jewelry in their mouths. Realistically, the danger of choking on a small item is many, many times greater than the risk of toxicity, which is why many items of jewelry simply aren't suitable for young children, and it all becomes a buyer beware issue.
All that said, the fear of lead has been overblown in the media, media being there primarily to entertain rather than really inform. Most of us do not eat our jewelry. Until the 1970s we had lead plumbing in our homes, and came to no harm, and prior to 2005 we were all wearing toxic costume jewelry. In actual fact the risk from the lead content was slim to none. I have been working with this stuff for 20 years, 7 days a week. If it was harmful, I think I would show signs by now!
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