Retention of the metabolized trace elements in biological tissues following different drying procedures: I. Antimony, cobalt, iodine, mercury, selenium and zinc in rat tissues

Abstract

Loss of Sb, Co, I, Hg, Se and Zn during freeze-drying and oven-drying at 80, 105 and 120 °C were studied in rat tissues that contained metabolized radioactive isotopes. No loss was observed for any of the 6 elements on freeze-drying. However, tissue-specific differences were observed in many cases for Hg, Se, I and Sb on oven-drying. A significant loss of Hg was observed in liver even at 80 °C, and for brain 105 °C. Se was lost from whole blood, brain, lung and muscle at 120 °C. Sb was lost from whole blood at 105 °C, but from brain, kidney, lung and spleen at 120 °C. Iodine was also lost from whole blood, kidney, blood serum, erythrocytes, brain, lung and muscle at 120 °C. Although the losses were statistically significant, they remained in most cases between 2 and 10%, with the exception of Hg at 120 °C, where the loss in some of the tissues were unpredictable. For urine, freeze-drying and oven-drying at 80 °C was found to be relatively safe for Hg and I. At 105 °C and above, serious loss of Hg was observed. In this experiment, the elements Zn, Co, Sb and Se were not studied for urine.