Cancer incidence among Finnish male cobalt production workers in 1969-2013: a cohort study.

Background: There is inadequate evidence for the carcinogenicity of cobalt and cobalt compounds in humans. Consequently, the International Agency for Research on Cancer (IARC) has evaluated cobalt metal without tungsten carbide as possibly carcinogenic to humans (Group 2B). The aim of the study was to assess the risk of cancer among workers employed in a Finnish cobalt plant since the beginning of production in 1968.

Cancer risk among workers at a copper/nickel smelter and nickel refinery in Finland.

A total of 1,388 workers employed for at least 3 months at a copper/nickel smelter and nickel refinery were followed up for cancer from 1953 to 1987 through the Finnish Cancer Registry. There were 1,339 male and 49 female workers, making a total of 27,130 and 706 person-years, respectively. All of the women worked in the refinery, which opened in 1960, the same year the smelting of nickel began.