Occupational exposure to chromium and nickel in Finland--analysis of registries of hygienic measurements and biological monitoring.

Two large data bases, one with the results of analyses on total dust, nickel, total and hexavalent chromium, and the other, with concentrations of chromium and nickel in workers' urine, have been accumulated in the Finnish Institute of Occupational Health. Data were analysed to assess occupational exposure to chromium and nickel during the last decade, using the International Standard Industrial Classifications for grouping industrial activities. Number of analyses was highest in fabricated metal products manufacturing, and welders and sheet metal workers were the largest and most heavily exposed groups. Occupational exposure limits were exceeded in 15.8% of all chromium measurements (500 micrograms m-3 for total chromium and 50 micrograms m-3 for hexavalent chromium). Recommended biological action level (BAL) (1.0 mumol l.-1) was exceeded in 0.8-7.1% of the cases in different years. Altogether, 18.3% (range 7.6-28.3%) of the air nickel measurements were higher than the occupational exposure limit for nickel compounds (100 micrograms m-3), but only 0.2-3.1% of results exceeded the BAL for nickel (1.30 mumol l.-1).