Children are particularly sensitive to lead poisoning. Long-term biting pencils can lead to lead poisoning, affect intellectual development and lead to behavioral disorders. Besides, the pencil itself is dirty. Biting a pencil will not only make people sick, but also lead to crooked teeth. Therefore, children should not bite the tip of a pencil.
The main components of a pencil
The main components of pencil lead are graphite and clay. Graphite is a scaly solid with metallic luster. There are carbon-carbon chemical bonds. These layers are van der Waals forces. Carbon-carbon chemical bonds are very stable. This is very difficult.
This is why both diamonds and graphite are made of carbon, but their physical properties and prices are quite different. Nothing in the human body can break the carbon-carbon chemical bond, so it is safe to say that pencil lead is safe (unless the clay added in it is harmful to human health).
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