Occupational exposure to chromium and nickel in the 1980s in Finland

Two large data bases accumulated from the 1980s at the Finnish Institute of Occupational Health, one with results on urinary chromium and nickel analyses and the other with results on total and hexavalent chromium and nickel, were compiled and analysed in order to clarify the occupational exposure during the 1980s, and to reveal possible trends in the exposure of workers in different jobs. The data were processed in three batches: years 1980–1982, 1983–1985 and 1986–1989. The median values of urinary chromium exceeded the biomonitoring action level, BAL, in metal workers, and the mean values exceeded the BAL in both metal workers and plasma cutters. Among all worker groups the median values of urinary chromium remained quite stable during the study period. The median values of urinary nickel concentration did not exceed the BAL in any worker group studied, but an increasing trend was observed among moulders. In the breathing zone of grinders, the median value of total or trivalent chromium exceeded the occupational exposure limit, OEL. The median of hexavalent chromium concentration in the breathing zone of metal sprayers and spray painters was higher than the OEL. No decreasing trend in exposure could be observed during the 10-year period in breathing zone air.