Lead(II) removal through biosorption on baker's yeast during biomass production was studied to estimate the level of uptake from contaminated molasses medium and to monitor its impact on cell growth. Lead(II) additions had significant negative effects on growth. Concentrations above 50 mgl(-1) resulted in a 50% reduction in growth rate and 60% lower overall biomass yields compared to controls. Nevertheless, the decrease in yeast biomass did not lead to decreased lead(II) uptake, on the contrary the biosorption ability was higher at higher initial lead(II) concentrations. (C) 2003 Elsevier Science Ltd. All rights reserved.