Toxicity of 90Sr inhaled in a relatively insoluble form by Beagle dogs. XIV

Beagle dogs were exposed by inhalation to 90Sr in a relatively insoluble form to study long-term health effects. Lung burdens ranged from 0.12 to 96 μCi of 90Sr/kg body weight. High levels of exposure resulted in radiation pneumonitis and pulmonary fibrosis; lower level exposures caused long-term effects, including cancer of the lung, heart, and tracheobronchial lymph modes. Most of these tumors were hemangiosarcomas. Two control dogs and two 90Sr-exposed dogs died or were euthanized during the past year. One exposed dog died with hemangiosarcoma of the spleen; the other exposed dog died with pulmonary thrombosis. One control dog died of pulmonary carcinoma, and the other control dog died of a carcinoma of the bladder. The remaining 19 exposed and 11 control dogs are being maintained for lifetime observation