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Agents Classified by the IARC Monographs, Volumes 1–132

Group 1 Carcinogenic to humans 122 agents
Group 2A Probably carcinogenic to humans  93 agents
Group 2B Possibly carcinogenic to humans 319 agents
Group 3 Not classifiable as to its carcinogenicity to humans 501 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 the IARC Monographs Q&A for answers to commonly asked questions on the evaluation process.

Although care was taken in preparing these lists, mistakes may be present.

If you find an error, please notify us at imo@iarc.who.int.

Last update: 12 August 2022