title: ECOSYS-87: model calculations of the activity in cattle meat related to deposition time and feeding regimes after a nuclear fallout.
abstract: The radioecological model ECOSYS-87 was used to evaluate the effect of countermeasures for reducing the ingestion dose by eating cattle meat after an accidental release of radioactive material. Calculations were performed using a database adapted to Swiss conditions for the case that (1) contaminated grass or hay is replaced by clean fodder; (2) the last 100 days before slaughter, taking place one year after an accident, only uncontaminated fodder is given; and (3) alternative feeding regimes are chosen. Seasonal effects were considered by doing all calculations for a deposition at each month of the year. Feeding uncontaminated forage 100 d before slaughter (case 2) proved to be the most effective countermeasure and reduced the integrated activity in meat by 90% to 99%. The effect of replacing contaminated grass (case 1) was less uniform and depended strongly on the time a deposition occurred. In this case the reduction was between 50% and 100% one year after deposition. The substitution of contaminated hay (case 1) was less effective compared to the substitution of grass. The choice of alternative feeding regimes (case 3) led to a reduction of the integrated activity of up to 40% one year after deposition. The present model calculations clearly reveal the importance of the seasonality and demonstrate the usefulness of such calculations as a basis for generating countermeasures in decision support systems.
authors.affiliation: Paul Scherrer Institut, Div. for Radiation Hygiene, Switzerland.
authors.forename: T K
authors.initials: TK
authors.lastname: Riesen
authors.forename: J
authors.initials: J
authors.lastname: Gottofrey
authors.forename: H J
authors.initials: HJ
authors.lastname: Heiz
authors.forename: A
authors.initials: A
authors.lastname: Schenker-Wicki
mesh_terms: D000821:Animal Feed; D000818:Animals; D002417:Cattle; D002588:Cesium Radioisotopes; D004463:Ecology; D005507:Food Contamination, Radioactive; D007457:Iodine Radioisotopes; D008460:Meat; D008962:Models, Theoretical; D011005:Plutonium; D006109:Poaceae; D011847:Radioactive Fallout; D018788:Radioactive Hazard Release; D012621:Seasons; D013326:Strontium Radioisotopes; D013557:Switzerland; D013997:Time Factors
chemical_list: D002588:Cesium Radioisotopes; D007457:Iodine Radioisotopes; D011847:Radioactive Fallout; D013326:Strontium Radioisotopes; D011005:Plutonium