A carcinogen a physical, chemical, or biological agent that increases the risk of cancer by altering cellular metabolism or damaging DNA directly within a cell. This damage interferes with normal biological processes, leading to uncontrolled cell growth and the eventual formation of tumors. carcinogens are classified by international health agencies, such as the IARC, into categories ranging from “Group 1” (definitely carcinogenic to humans) to Group 3 (not classifiable) based on the level of scientific evidence available.
greek; - Roots:Karkinos (meaning “crab” or “cancer”) + -gen (meaning “producer” or “source”).
Historical Context: The term was coined as a shorthand for “cancer-generator,” first appearing in English medical texts in the mid-19th century. carcinogen(n.)::“cancer-causing substance,” 1853, from carcinoma “malignant tumor, cancer” + -gen.