The effect of disodium EDTA, as an additive, on the crystallization of struvite and carbonate apatite was studied. The growth of struvite crystals and carbonate apatite occurred in the solution of artificial urine at 37 degrees C and at the condition emulating real urinary tract infection. The results demonstrate that the addition of disodium EDTA increases the induction time and decreases the growth efficiency compared to the baseline (without disodium EDTA). The struvite crystal mean and median diameters were found to decrease in the presence of disodium EDTA but the crystal morphology and habit remain almost unchanged. Disodium EDTA has demonstrated its potential to be further investigated in the presence of bacteria and in vivo conditions. (C) 2013 Elsevier B.V. All rights reserved.