Toxicity of 91Y inhaled in a relatively insoluble form by Beagle dogs. XVI

Beagle dogs were exposed by inhalation to aerosols of 91Y in fused aluminosilicate particles, resulting in initial lung burdens ranging from 11 to 360 μCi (0.4-13 MBq) 91Y/kg body weight. These 96 dogs, plus 12 controls, were maintained for life-span observation of toxic and carcinogenic effects. Dogs with the highest lung burdens died at early times with radiation pneumonitis. At later times, tumors were seen in lungs, nasal cavity, heart, and tracheobronchial lymph nodes; these organs received the highest radiation doses. Observations are continuing on the 5 exposed and 3 control dogs that remain alive 5120 to 5605 days after exposure. 2 figures, 1 table