Incidence of cancer in the mineral-wool producing industry in Norway

This study concerned the Norwegian phase of a European collaborative investigation on workers in man-made mineral fiber production. A study population of 2,361 men from four Norwegian plants was examined for mortality and cancer incidence, especially lung cancer, based on a comparison of observed and expected figures, the latter determined according to the five-year age-specific mortality and incidence rates for the entire country. Violent deaths among workers with less than one year of employment represented the only significant mortality excess. A borderline, statistically significant excess risk was found for cancer of the buccal cavity and pharynx, but the fact that the excess occurred in one factory only led to the assumption that the risk was associated with factors other than mineral wool. An excess risk for lung cancer was also found among those with 20 years or more since first exposure (9 observed and 4.36 expected). The risk that emerged was presumably initiated before 1960, when the environmental conditions were more hazardous than later.