Who determines how carcinogens are classified?
Several agencies (national and international) are responsible for determining the cancer-causing potential of different substances. International Agency for Research on Cancer The International Agency for Research on Cancer (IARC) is part of the World Health Organization (WHO). Its major goal is to identify causes of cancer. The most widely used system for classifying carcinogens comes from the IARC. In the past 30 years, the IARC has evaluated the cancer-causing potential of more than 900 likely candidates, placing them into one of the following groups: • Group 1: Carcinogenic to humans • Group 2A: Probably carcinogenic to humans • Group 2B: Possibly carcinogenic to humans • Group 3: Unclassifiable as to carcinogenicity in humans • Group 4: Probably not carcinogenic to humans Perhaps not surprisingly, based on how hard it can be to test these candidate carcinogens, most are listed as being of probable, possible, or unknown risk. Only a little over 100 are classified as “carcinogenic t
