Toxicological Problems with the Redy System

Dialysate from the REDY dialysis system was examined for toxic elements, special attention being paid to the content of zirconium and aluminium. Also investigated was the concentration of formaldehyde in the rinsing fluid of three consecutive washings. The amount of zirconium and aluminium found in the dialysate was negligible. The concentration of formaldehyde was alarmingly high after two consecutive washings, a considerable amount (less than 50 mg) still remaining after three washings. It is recommended that at least three consecutive washings be performed, and that, if possible, formaldehyde be substituted by another antiseptic. Of special interest was the finding of a very high concentration of boron in the dialysate. It is suggested that this metal, which is a potentially toxic substance, may emanate from the patient. It is concluded that use of the REDY system carries no obvious toxicological risk.