Drawing pencils do not contain lead. Although the word "lead" is in the name, this is a historical misconception. Modern pencil leads are made from a mixture of graphite and clay in specific proportions.
Historical background: In ancient Greece and Rome, people did use lead rods made of metallic lead for drawing lines and making marks. However, the main components of modern pencil leads are graphite and clay.
Properties of graphite: Graphite is an allotrope of carbon, non-toxic and harmless, and possesses good electrical conductivity and lubricating properties.