Iirc lead poisoning isn’t much of an issue because your body encapsulates it, preventing the body from absorbing it.

Metal detectors are a non issue. My dad has several pieces of metal in his spine from surgeries. He occasionally sets off metal detectors, but it’s never been a huge issue with security. It’s more common than you think. People have metal plates, screws and general hardware put in surgically for a variety of reasons. It’s fairly common.