How do mutagens cause cancer?

Mutagens are physical, chemical, or biological substances that cause permanent damage to a cell’s genetic material, resulting in a mutation. 

Mutagens cause cancer by altering the structure of DNA, causing mutations in the DNA. These DNA mutations can be deleterious and can cause loss of function or impaired or deviant functioning for a particular gene. Genes contain information for synthesizing proteins, which control many vital functions including cell growth. Genetic mutations can alter the way proteins function. Some mutagens alter protein functions in ways that result in healthy cells becoming cancerous.