Simply wearing jewelry containing lead or cadmium is unlikely to be harmful because almost no lead or cadmium enters the body through direct contact with the skin. Jewelry is one of the products that have been most withdrawn from the market due to excessive levels of substances such as lead or cadmium. This is more common on jewelry made outside the U.S. UU.
Jewelry may also contain nickel, a metal that gives them a shiny silver finish. Nickel is known to irritate the skin. Nickel is a natural metal with a silver finish. It is used on many items, such as jewelry, zippers, eyeglass frames, and consumer electronics.
It's not toxic, but it's known to irritate the skin. The rash usually doesn't spread beyond where the nickel comes in contact with the skin. Symptoms may last up to four weeks after exposure. Lead is often used to shape and stabilize jewelry, and is very common in vintage and plastic pieces.
Swab tests can be used to quickly identify the presence of lead in jewelry, or you can pay an accredited laboratory to do a more thorough test. An amount of lead lower than 5,000 ppm is considered safe, but any amount of lead is dangerous if absorbed by the body. Try and care for lead-based jewelry to stay safe. In general, some of the materials considered safe for use as inclusions for the retail jewelry class include leaded glass, which is common in crystals, including rhinestones.