Prussian Blue Decorporation of 137Cs in Humans and Beagle Dogs

Abstract

Prussian blue (PB) was used to enhance the elimination of 137 Cs from 46 individuals contaminated in an accident in Goiânia, Brazil, in 1987, PB dosages administered to the victims varied from I to 3 g.d -1 for children and from 3 to 10 g.d -1 for adolescents and adults. To complement human data in the evaluation of the effectiveness of PB and its relation to age, a 41 day study was conducted using immature (4.7 months old). young adult (2.4 year old) and aged (13.5 years old) male beagle dogs. The mean biological half-times for the Goiânia people under PB treatment were 24 ± 3 days, 30 ± 12 days and 25 ± 11 days, for children, adolescents and adults, respectively. The mean reductions of half-times were 43%, 46% and 69%, respectively. The effect of PB was shown to be independent of age and the administered dose. Similar results were found in dogs: the mean biological half-times related to the second component of the equation were 11, 15 and 13 days for the immature, young adult and aged dogs. respectively. indicating a reduction of the clearance half-times of 45%, 45% and 63%. The experiment in dogs has shown that when the PB is administered immediately after a caesium intake. its effectiveness is greater in immature than in aged dogs. The percentages of the initial body burden remaining 41 days after caesium intake were 4%, 12% and 8% for the immature, young adult and aged dogs. repectively. This age-related effect correlates with the increased fraction of 137 Cs eliminated with the fast clearance half-time, and was greater in immature than in aged dogs.