The Effect of Sustained Release Boli with Ammoniumiron(III)-hexacyanoferrate(II) on Radiocesium Accumulation in Sheep Grazing Contaminated Pasture

Abstract

Sustained release boli with the cesium binder ammonium iron(III)-hexacyanoferrate(II) (AFCF) were tested under practical conditions for sheep grazing on pastures contaminated with radiocesium (134Cs+137Cs) from the Chernobyl fallout. Two types of AFCF boli were developed: boli without a protective surface coating intended to last 4-8 wk; and boli coated by a wax-mixture with an extended duration of 10-12 wk. From 1989 to 1993 we measured the effect of wax-coated and uncoated boli administered at various times during the grazing season to a total of 3,248 animals. Reductions in radiocesium levels in meat of sheep were measured by in vivo monitoring. Administration of AFCF boli without a wax-coating reduced the mean radiocesium levels in lambs by 43-75% over a 4-8 wk period, and administration of the wax-coated AFCF boli reduced the mean radiocesium levels by 48-65% over a 9-11 wk period. The coefficients of variation in meat radiocesium levels were similar in treated and control groups at the end of the observation period, showing that the reduction of meat radiocesium values was homogenous throughout the treated groups. The boli giving sustained release of AFCF is a labor-saving and cost effective countermeasure for sheep grazing radiocesium contaminated pastures.

AFCF and clinoptilolite use in reduction of 137Cs deposition in several days' contaminated broiler chicks

“…The best cesium binding effects were recorded for AFCF cesium binder, which confirmed the earlier findings by Arnaud et al (1988), Hove and Ekern (1988), Hansen et al (1996) and Paasikallio et al (2000). This cesium binder incorporated in the feed (group 3) after 3 days of contamination reduced 137 Cs deposition in the breast meat by 68%, in liver by 81% and in gizzard by 68%.…”

“…The commonly used compound is AFCF e ammonium ferric hexacyanoferrate (Arnaud et al, 1988;Hove and Ekern, 1988;Hansen et al, 1996;Paasikallio et al, 2000). The reduction of 90e 98% was achieved in cows with 3 g of AFCF daily; in calves and pigs with 2 g of AFCF daily (Giese, 1988) and in broilers with 0.2 g of AFCF daily per chick (Vitorovic, 1993;Rachubik and Kowalski, 2001).…”

Environmental consequences of the chernobyl accident and their remediation: twenty years of experience. Report of the chernobyl forum expert group ‘environment’

“…Boli are particularly favourable for infrequently handled free-grazing animals, as the boli can be administered when animals are gathered for routine handling operations. For use in extensive systems, the boli can be given a protective surface coating of wax to delay the onset of AFCF release, so that effectiveness is increased at the time when animals are collected for slaughter (Hansen et al 1996). Brynildsen et al (1996) estimated that the use of boli as a countermeasure for sheep was 2.5 times as cost effective as feeding with uncontaminated feed.…”

Sustainable restoration and long-term management of contaminated rural, urban and industrial ecosystems

“…Amongst these were rumen dwelling boli, typically containing 15 % AFCF and coated in wax to extend their effectiveness. The administration of three waxed boh has been shown to reduce radiocaesium contamination of sheep by c. 50-65% over a period of 9-11 weeks [8]. Hexacyanoferrate boli have also been used in contaminated areas of the fSU.…”

“…Boli can be expected to achieve a c. 50% reduction in radiocaesium activity concentrations in meat and milk [8]. Therefore, if the aim of intervention is to reduce contamination to levels below the intervention limit, the initial activity concentration can be no more than twice the limit.…”