Subcellular Distribution of Cadmium within the Lung and Kidney after Cadmium Oxide Inhalation Exposure

摘要

Male Sprague-Dawley-rats were exposed for 5 or 7 weeks to cadmium-oxide (1306190) aerosols at relatively low levels of 35 to 275 micrograms/cubic meter and sacrificed at 4 to 8 months of age. Cadmium was concentrated by the kidney and lung tissues in the cytoplasmic soluble fraction and in the connective tissue. Of the total cadmium present, 50 and 70 percent was associated with the kidney and lung supernatants, respectively. Even so, the total amount of the cadmium retained was far less than reported in the literature. Using an approximate lung volume of 2 cubic centimeters and a breathing rate of 80 times per minute, the percent retention in the lung was about 0.03 percent and in the kidney, about 0.003 percent. These low values may indicate an efficient clearance mechanism by the body which can be supported by the finding of virtually no cadmium present in the lung washings and very few particles present in the cell bodies or alveolar ducts on microscopic examination. However, after 6 weeks exposure, a slight amount of perivascular lymphoid hyperplasia was observed.