Mortality of high nickel alloys workers: an update 

The mortality experience of a cohort of 31,165 workers employed in the production of and fabrication of products from high nickel alloys was evaluated through 1988.  This cohort comprises male and female workers from 13 plants throughout the US and represents a substantial proportion of all such workers worldwide. Mortality was evaluated for 61 cause specific categories with emphasis given to malignant neoplasms, particularly lung cancer.  Over 10,000 deaths were identified, including 2,674 cancers of which 955 were lung cancer.  In addition to comparing the mortality experience of the workers to the general US population, comparisons were made to local populations in geographic proximity to each of the 13 plants, and to an industrial population of steelworkers whose socioeconomic status was most likely similar to that of the high nickel alloys workers.  The use of local death rates controls for geographic variability seen in many cause specific mortality rates.  Comparison to  a contemporary population of steelworkers takes into account selection factors associated with health in worker populations.  When the overall cohort and work area specific mortality was compared to the US, a modest excess of approximately 20% was noted for lung cancer.  However, the magnitude of these findings diminished when the local referent group was used as the comparison.  The implication of these findings will be discussed.