Radiocaesium transfer to sheep's milk as a result of soil ingestion

• Published in: The Science of the total environment Vol. 136; no. 1-2; pp. 13 - 24
• Main Authors: Assimakopoulos, P.A., Ioannides, K.G., Karamanis, D.T., Pakou, A.A., Stamoulis, K.C., Mantzios, A.S., Nikolaou, E.
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier B.V 15.08.1993; Elsevier Science
• Subjects: Animals; Biological and medical sciences; Biological Transport; CAESIUM; CESIO; CESIUM; Cesium Radioisotopes - administration & dosage; Cesium Radioisotopes - analysis; Cesium Radioisotopes - pharmacokinetics; CONTAMINANTES RADIACTIVOS; EWE MILK; Female; Food industries; Food toxicology; Fundamental and applied biological sciences. Psychology; LAIT DE BREBIS; LECHE DE OVEJA; Milk - chemistry; Milk - metabolism; Models, Biological; OVIN; OVINOS; POLLUANT RADIOACTIF; POLLUTION DU SOL; POLUCION DEL SUELO; RADIOACTIVE POLLUTANTS; radiocaesium contamination; SHEEP; Sheep - metabolism; sheep milk; soil ingestion; Soil Pollutants, Radioactive - administration & dosage; Soil Pollutants, Radioactive - pharmacokinetics; SOIL POLLUTION; trace element transport; transfer coefficient; soil ingestion; radiocaesium contamination; sheep milk; trace element transport; transfer coefficient; Soils; Quality control; Radioactive contamination; Cesium; Modeling; Ewe milk; Mass transfer
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/0048-9697(93)90293-F

Soil ingestion as a source of radiocaesium contamination to ruminants was studied by measuring the transfer coefficient to sheep milk. Eight lactating ewes, housed in individual metabolism cages, were used. Fifty grams per day of heavily contaminated sandy topsoil, collected in 1990 from the Chernobyl area, were administered orally to the animals for a period of 1 week. The daily dose intake in 137Cs was 1835 Bq day−1. During this contamination period, daily milk production and excreta output were measured. The ewes were monitored for an additional 7 day decontamination period, while they fed on uncontaminated feed. Transfer coefficients were obtained through a best fit (minimum χ2) of the data to predictions of a linear compartment model. The values obtained were fm = (2.6 ± 0.7) × 10−2 and fu = (5 ± 2) × 10−2 days kg−1 for radiocaesium transport to milk and urine, respectively. These results suggest that soil ingestion can be a major source of radiocontamination for sheep and other free-grazing ruminants. Comparison of our results with soil-to-milk transfer coefficient values derived in two recent independent experiments suggests that there might be a strong dependence of radiocaesium availability on soil composition.