Exposure of animals to ionizing irradiation may be a important pathway fortransfer of radionuclides to human food chain, thereby adding to the exposureburden. Therefore, radiation control of animal feeds and animal products willreduce risk for radioactive hazards to human health. The study was carried out inorder to detect the natural radioactivity in edible parts of pigs, excrements andfeeds in one commercial pig breeding farm in Macedonia. Therefore, 40K, 212Pb,214Pb, 228Ac, 235U, 241Am, 212Bi, 214Bi, 232Th, 7Be and 226Ra were measured usinggamma spectrometry. Gamma spectrometer Canberra Packard with a high-puritygermanium detector and Marinelli beakers (1 l capacity) were used for the samplesmeasurement. The most prominent gamma energies observed in the spectrabelonged to the naturally occurring radionuclides 40K, 235U and 232Th. Othernuclides if present occurred infrequently at low levels. The result show that 40Kmade the largest contribution to the specific radioactivity in all the samples. Themean activity concentration of the 40K in edible organs (kidney and liver), muscle,excrements and feeds was: 73.39±9.109 Bq/kg; 111.26±3.88 Bq/kg; 298.80±38.51Bq/kg; 83.60±10.279 Bq/kg, respectively. The 235U and 232Th were detectible onlyin feed samples (0.53±0.293 Bq/kg; 163.69±23.791 Bq/kg, respectively) andsamples from excrements (0.25±0.021 Bq/kg; 58.17±1.062 Bq/kg, respectively).The other radionuclides were detected only in few samples and the measuredactivities were below the detection limit. If we take in consideration the activityconcentration of the most frequently occurred 40K found in all samples, than therewas statistical significant difference between radioactivity concentration in organs,muscle, excrements and feeds (p<0.001).
THE DETERMINATION OF d(-)- AND l(+)-GLUTAMIC ACID IN PROTEIN HYDROLYSATES
