Three different dialysis procedures have been investigated and compared with respect to the efficacy of aluminium elimination in intoxicated dialysis patients. For this purpose ten patients with increased serum aluminium have been treated for two months with the chelator DFO. The effect of DFO on the aluminium clearance has been investigated. In spite of difficult conditions during studies due to an unexpected cumulation of severe adverse effects of DFO, some statements given here may be of value for the care of hemodialysis patients: 1. Both, the commonly used cuprophan filters as well as the newer highly permeable dialysis membranes like the polysulfone membrane used in our study, permit a steady but low elimination of aluminium during a dialysis session without significant difference in efficacy. A prerequisite, however, is a very low level of aluminium in the dialysate. 2. DFO induces a dose-dependent mobilization of aluminium accumulated in the tissue. The level of plasma aluminium increases distinctly, dialysable aluminium-DFO complexes are produced, and marked amounts of aluminium can thus be eliminated by the use of DFO. 3. IF DFO is used, even the economical cuprophan membrane CF1511 may lead to a satisfactory elimination rate of aluminium. Equal increase of elimination rate is achieved whether the Cuprophan membrane CF1511 is combined with the hemoperfusion filter Alukart or the highly permeable polysulfone membrane F60 is used alone. This is of importance particularly in cases of severe intoxication with aluminium. The polysulfon dialysator may be preferred to conventional membranes combined with hemoperfusion because of the simpler handling. 4. In order to prevent accumulation of aluminium in dialysis patients, besides the use of dialysates poor in aluminium, phosphate binders containing aluminium should be avoided completely if possible. They may be replaced by the two phosphate binders calcium carbonate and calcium acetate and a diet poor in phosphates. The use of aluminium-containing phosphate-binders should be restricted to exceptional cases such as patients with hypercalcemia, severe intolerance of calcium-containing phosphate-binders or patients with hyperphosphatemia that cannot be treated otherwise. 5. Finally, regular controls of plasma aluminium levels are mandatory in dialysed patients. In cases with an increase over 50 micrograms/l and positive DFO test, DFO treatment should be initiated. Low doses of 10 mg/kg body weight DFO per week are actually in use for those cases.(ABSTRACT TRUNCATED AT 400 WORDS)