Agents Classified by the IARC Monographs, Volumes 1–109

           Group 1 Carcinogenic to humans 113 agents
Group 2A Probably carcinogenic to humans   66
Group 2B         Possibly carcinogenic to humans 285
Group 3 Not classifiable as to its carcinogenicity to humans             505
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.

  • List of classifications by alphabetical order

  • List of classifications by CAS® Registry Number order

  • List of classifications by Group

  • List of classifications by cancer site

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


  • Although care was taken in preparing these lists, mistakes may be present.
    If you find an error, please notify us at imo@iarc.fr.

    Last update: 25 July 2014