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Agents Classified by the IARC Monographs, Volumes 1–128

Group 1 Carcinogenic to humans 121 agents
Group 2A Probably carcinogenic to humans  89 agents
Group 2B Possibly carcinogenic to humans 315 agents
Group 3 Not classifiable as to its carcinogenicity to humans 497 agents

For definitions of these groups, please see the Preamble.

It is strongly recommended to consult the complete Monographs on these agents, the publication date, and the list of studies considered.  Significant new information might support a different classification.
For agents that have not been classified, no determination of non-carcinogenicity or overall safety should be inferred.

See Preventable Exposures Associated With Human Cancers (Cogliano et al., 2011)

Read Questions and Answers: IARC Monographs on the Identification of Carcinogenic Hazards to Humans

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Last update: 18 February 2021