How do I tell if my gl beads are made with lead?

If they come from China then they are not Czech gl, which would also contain a certain amount of lead. This is how 'crystal' gl is made, as opposed to the natural crystal stone. Billions of us around the planet are wearing these crystal gl beads. It might be worth finding out from your National Health agency (don't know what yours is called) what the regulations are regarding imports of gl beads and jewellery from China are. Certainly no problem in the UK.