The effect of dialysis on radiocaesium in man

Dialysis is used for cleaning the blood in patients with end-stage renal disease. The most common methods are hemodialysis (HD) and peritoneal dialysis (PD). Dialysis patients might constitute a critical group because of poor elimination of radioactive elements ingested. On the other hand dialysis may be a useful decontamination method for radioactivity. The effect of dialysis on the turnover of radiocaesium was studied in 10 HD patients and 4 PD patients. The dialysis fluid, which contains electrolytes and the metabolic waste products, was analyzed for radiocaesium. In this connection the patients were whole-body counted for radiocaesium and 40K. The results show that HD patients generally have a lower body burden of radiocaesium than normal subjects, while PD patients show normal levels. At steady state both dialysis methods eliminate slightly less radiocaesium than normal kidneys do, but in the case of HD during a much shorter time. The calculated effective half-life for radiocaesium was normal in the HD patients, and somewhat longer in the PD patients. Considering that HD is performed only for 12-15 h weekly, the elimination rate of radiocaesium by HD is much higher compared with that by normal kidneys. Thus, HD might constitute an important method for decontamination of radiocaesium after accidental internal contamination.