Availability of data on humans potentially exposed to suspected carcinogens in the Danish working environment.

For the majority of suspected carcinogens only little or no human evidence exists, and in general on-going epidemiologic studies fail to address this fast growing group of chemicals. A survey based on a Danish occupational surveillance system concerning data on present and historical import, production and use of the 167 chemicals evaluated by the International Agency for Research on Cancer as possible or probable carcinogens, shows that about 110 of these chemicals are on the market in Denmark at present. Only 32 are used in industry in relatively large quantities. For some of these chemicals it is possible to identify clusters of companies, including historical cohorts of potentially exposed workers. Measurements of airborne pollutants are available for some few of the suspected carcinogens, indicating decreasing time trends and various levels in different industries. In spite of some limitations, this information on potential exposure has on ad hoc basis been linked to an existing cancer registry based occupational surveillance system, and various studies based on the total body of data are on-going, as a preliminary approach to give at least some human evidence to some widespread animal carcinogens.