Three human probiotics, Lactobacillus rhamnosus strains GG and LC-705, and Bifidobacterium lactis strain Bb12, were found to bind the cyanobacterial peptide toxin microcystin-LR from water solutions. The highest removal percentage was 46%, observed with heat-treated L. rhamnosus strain GG (10(10) cells/ml) and a microcystin-LR concentration of 0.5 microg/ml during an incubation of 7 h at 35 degrees C.