Abstract
The IARC programme on the evaluation of the risk of chemicals to humans was initiated in the late 1960s in response to the request made to the Agency for information on environmental carcinogens. The programme, which has been implemented with the advice and the collaboration of a large number of international experts, is focused on the production of monographs on individual chemicals, groups of chemicals or complex exposures. The programme will shortly include also the evaluation of risks related to some of the most widely spread cultural habits. It has been, and still is, the policy of the programme to consider only published information in relation to biological data relevant to the evaluation of carcinogenic risks. One of the main limitations with regard to the possibility of accurately evaluating cancer risks was shown to be the shortage of information on the level of exposure to carcinogenic risk factors. To overcome such limitations it would appear that a close and continuous collaboration between experimentalists and epidemiologists be maintained.