Toxicity of 144Ce inhaled in a relatively insoluble form by Beagle dogs. XIV

The metabolism, dosimetry and effects of 144Ce inhaled in fused aluminosilicate particles are being investigated using Beagle dogs to assess the long-term biological consequences of the release of relatively insoluble aerosol forms of 144Ce that could occur in nuclear accidents. One hundred eleven dogs were exposed to aerosols of 144Ce in fused aluminosilicate particles to yield initial lung burdens of 0.0024 to 210 μCi/kg body weight and 15 control dogs were exposed to nonradioactive fused aluminosilicate particles. To date, 73 144Ce-exposed and 4 control dogs have died or were euthanized at 143 to 4759 days after inhalation of 144Ce. Observations are continuing on the 39 144Ce-exposed and 11 control dogs remaining alive at this time, at least 3702 days (approx. 10 years) after exposure