There are several possible explanations for why a person’s hands might have a metallic smell. Here are some possible causes:

1. Exposure to metals: If a person’s hands come into contact with certain metals, such as copper or iron, it can cause a metallic smell. This could happen if a person works with these metals or if they handle objects that have been in contact with these metals.
2. Bacterial or fungal infections: Certain types of infections, such as bacterial or fungal infections of the skin, can cause a metallic smell.
3. Medications: Some medications, such as those used to treat high blood pressure or heart problems, can cause a metallic smell on the skin.
4. Genetic conditions: In rare cases, a genetic condition called trimethylaminuria (TMAU) can cause a person to have a strong metallic or fishy smell on their skin, breath, and sweat. TMAU is caused by a deficiency in an enzyme that breaks down certain compounds in the body, leading to a build-up of trimethylamine.
5. Other factors: Other factors that can cause a metallic smell on the skin include exposure to chemicals, use of certain skincare products, and certain medical conditions such as diabetes or kidney disease.

If a person is concerned about a metallic smell on their hands, they should see a doctor for proper diagnosis and treatment. The doctor will consider the person’s medical history, conduct a physical examination, and may order tests to determine the cause of the smell.