evaluation of reverse osmosis system for improving water quality used for dialysis fluid

background: the chemical quality of water used for dialysis fluid is a vital factor in the overall care received by dialysis patients. therefore, water used for this purpose should be treated with advanced methods before use for dialysis. the objective of this study was to assess the efficiency of reverse osmosis systems to improve water quality used for dialysis fluid. methods: in this descriptive study, 40 water samples were collected from inlet and outlet of reverse osmosis systems of 5 hemodialysis services of isfahan hospitals, iran, during april to august 2011. the samples were analyzed for physicochemical parameters including residual chlorine, chloramines, ph, hardness, al, f, cu, mn, cd, cr, pb, ni concentration according to the standard methods for examining water and waste water. findings: the results of this study showed that the reverse osmosis systems significantly reduce the amount of residual chlorine, chloramines, hardness, na, k, f, no 3 , so4 and mn, but it could not significantly reduce the amount of cu, zn, cd, cr, pb and al. however, the results also showed that the amount of no 3 , hardness, pb, cd, cr and al in outlet samples of reverse osmosis systems was higher than the value given by association for the advancement of medical instrumentation (aami). conclusion: reverse osmosis systems could improve the quality of water used for hemodialysis but they do not reduce the level of some contaminant to the recommended values for dialysis fluid. this condition may be unsafe for hemodialysis patients. therefore, a rigorous control of chemical contaminants is necessary in order to ensure that hemodialysis therapy is in a good quality.