The human nose can detect 10,000 distinct smells. It's constantly bathed in a mixture of smells. Odor molecules dissolve in the mucus lining within the nasal cavity. On surface of the mucous membrane, there millions of smell receptors. Each receptor detects one specific smell. Once the right smell attaches to the corresponding receptor, an electrical signal is sent straight to the emotional part of the brain. This causes us to associate certain smells with certain emotions or memories.
The nose is surrounded by cartilage, making it a slow healer and more vulnerable to scarring and infection. Nose piercing is not medically recommended.
Sniffing or snorting drugs can create a painful ulcer in your nasal septum.
Working long hours with chemicals that create fumes can kill your sense of smell.
Using inhalants could kill you instantly on the first try!
In short, try to avoid all of the above.