What is IARC?
IARC, the International Agency for Research on Cancer, operates under the auspices of the World Health Organization. IARC scientists evaluate the weight of evidence that a compound can influence the risk of cancer in humans.
How does IARC classify compounds with respect to their cancer risk?
IARC classifies compounds into four groups based on the available scientific evidence for increasing cancer risk in animals and humans. The four classifications are Groups 1, 2A, 2B, 3, and 4, which correspond to decreasing available evidence for cancer risk.
|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|
Probably not carcinogenic to humans
For more information on IARC methods and classifications, please see the IARC Preamble.
How many compounds have received a classification of from IARC?
Of the more than 900 compounds classified by IARC to date, only one compound has been classified as Group 4 (probably not carcinogenic to humans). Over 500 have been classified as Group 3 (not classifiable as to its carcinogenicity), and over 400 have received a classification of Group 2B or higher. For a complete list of IARC classifications, please see Agents Classified by the IARC Monographs.
Are there compounds present in foods that have been classified as Group 2B or higher by IARC?
Yes, compounds present in foods have been given a Group 2B or higher classification by IARC. Coffee itself is classified in Group 2B, although there is evidence that coffee is anti-carcinogenic. Other compounds in foods that are classified by IARC include acrylamide (Group 2A) and furan (Group 2B) that are formed naturally in food as part of normal cooking processes. Acetaldehyde and affeic acide are Group 2B compounds that occur naturally in foods such as fruits and coffee.
What does a classification of Group 2B mean?
IARC defines a Group 2B classification as “the agent is possible carcinogenic to humans.” This category is used by IARC when there is limited scientific evidence that a compound increases cancer risk in humans and less than sufficient evidence of an increased cancer risk in experimental animals.
Does this mean that consumption of food containing those compounds classified as Group 2B and above will cause cancer in humans?
No, the IARC classification does not mean that consuming food containing those compounds will cause cancer in humans.