Are bad smells harmful?

Asked by: Oscar Cossman, Leicester

Smells in themselves do not cause harm. A smell is a neural response to airborne molecules binding to receptors in the mucus membranes of your nose. You can't be harmed by a smell any more than you can by a colour.

But the chemical that causes the smell can harm you. In general, we have evolved so that harmful substances smell bad, to warn us.

Read more:

• I just bought a lovely new car, so why is the smell of it making me feel sick?
• Why do we associate citrus smells with being clean?

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