IARC classifies carcinogens into different groups based on the evidence of their carcinogenicity:
Group 1: Carcinogenic to humans. Group 2A: Probably carcinogenic to humans. Group 2B: Possibly carcinogenic to humans. Group 3: Not classifiable as to its carcinogenicity to humans. Group 4: Probably not carcinogenic to humans.
These classifications are based on a rigorous evaluation of available scientific evidence, including epidemiological studies and research on animal models.
