What elements react with lead in a sense that you know that lead is present in that object?

Question

I really need to know what elements react with lead and a way to measure the amount of lead in the object (i.e. lipstick, water)

Answer 1

If you're testing for lead in existing paint on walls, toys, or in formulations of various products; I think they use a portable X-ray fluorescence detector. (that's what they used when they checked the apartment I lived in. It will even detect lead that is covered under non-lead paint or other materials).

The problem with trying to test for lead by dripping some test reagant on something is the lead might not be very accessible to the reagent (like, for paint, the lead is trapped in a matrix of hardened alkyd resin or similar material, in lipstick, the lead would be in a very hydrophobic, oily material which might not react with a watery test solution and could lead to false negative tests.