What qualifies a chemical as a carcinogen?

A chemical is qualified as a carcinogen if it has been shown through scientific studies and research to cause cancer in humans or animals. This classification is based on evidence demonstrating that exposure to the chemical can lead to the development of cancerous cells or tumors. Organizations such as the International Agency for Research on Cancer (IARC) and the U.S. Environmental Protection Agency (EPA) assess chemicals for their carcinogenic potential based on a variety of factors, including laboratory studies, epidemiological data, and mechanisms of action.

While toxicity, instability, and flammability are relevant properties of chemicals, they do not inherently indicate a chemical's ability to cause cancer. Toxicity refers to the harmful effects a substance may have on living organisms, instability pertains to the likelihood of a substance to undergo chemical change or decomposition, and flammability describes a material's ability to catch fire. None of these properties directly relate to a chemical's capacity to induce cancer, which is the crucial factor for classification as a carcinogen.