Ash removal workers and maintenance workers are simultaneously
exposed to many metals during their work in biomass-
fired power plants. According to the measured concentrations
and the results of the Mixie programme, the most evident exposure-associated
health risk was that of cancer, followed by central
nervous system disorders, lower respiratory tract irritation, and fi-
nally upper respiratory tract irritation. Significant differences were
seen between biomass-fired power plants in the risks of cancer and
upper respiratory tract irritation. The highest combined risk for
different health effects was recorded during ash removal in the
recycled fuel-fired power plants. Due to findings of suspected supra-additivity
of combined metal concentrations (supra-additivity
of As and Cd, Mn and Pb, and As and Se), our results may underestimate
the additive risks of cancer, central nervous system
disorders, and upper respiratory tract irritation.