Agents Classified by the IARC Monographs, Volumes 1–122

Group 1 Carcinogenic to humans 120 agents
Group 2A Probably carcinogenic to humans   82
Group 2B         Possibly carcinogenic to humans 302
Group 3 Not classifiable as to its carcinogenicity to humans             501
Group 4 Probably not carcinogenic to humans     1

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)
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Last update: 30 July 2018