Radioecological model for transport of radioiodine and radiocesium in the food chains after radiological accidents and discharge of radioactive substances to atmosphere for study of mechanism of formation of internal radiation doses to population. Part 2. Description, formulation and metabolism of 131I and 137Cs in organs of beef cattle

Mathematical statement of 131I and 137Cs metabolism components of the radioecological model is presented. As a result of long-term experimental studies parameters of multi-compartment models of radioiodine containing and radiocesium containing Russian low producing cows were developed. There are some features of contaminating cow organs and milk depending on weather, feeding and housing after the Chernobyl accident. It was found that if cows began feed radionuclides-free forage no later than 3-5 days of feeding radionuclides-containing grass, integral activity of 131I in milk would effectively decline by 30-10 times. If cows began feed radionuclides-free forage no later than 5-10 days of feeding radionuclides-containing grass integral activity of 137Cs would effectively decline by 300-200 times. If cows begun feed radionuclides-free forage in 10-20 days efficiency of declining 131I and 137Cs in milk and 137Cs in meat would be about twofold. In the first year after the accident in contaminated area of Russia and Belarus transport of 137Cs from underground to above ground part of grass was non-significant.