Fused aluminosilicate

Fig. 6. Retention of lt4Ce in lung, liver, skeleton, and tracheobronchial lymph nodes after inhalation of Ce in fused aluminosilicate particles in Beagle dogs. The upper figure shows average data points and total ranges with solid line curves projected from the biological model, all of which include physical decay. The lower figure shows the same model projections only corrected for physical decay.

Table 13—Time integrated, uCe activity in lung, liver, and skeleton after inhalation of class D, W, and Y compounds and after inhalation of chloride, oxide and fused aluminosilicate particles, FAP, by beagles 1...

However, most of it was still in the thorax (either in lung or lymph nodes). The 144Ce in this case may have been serving only as a tracer for the vehicle, uranium, as did the l44Ce in fused aluminosilicate particles. 

Beagle dog inhalation l44Ce in fused aluminosilicate particles AMAD 1.6-2.2 pm o 1.3-1,6 3 mos 54 life span (in progress) pulmonary fibrosis, radiation pneumonitis, congenital heart failure 5/12 Yes hemangiosarcoma 4/12 Yes No hemangiosar- coma 1/12 Hanicka-Rebar (1978)... 

Beegle dog inhalation, 44Ce in fused aluminosilicate particles AMAD 1.6-2.3 pm o, 1.3—1.6 8-10.5 yr 54 life span (in progress) radiation pneumonitis, cong. heart failure, fibrosis 17/33 Yes bronchiolo alveolar carcinoma 3/33 No No Hahn et of. (1978b)... 

Fig. 12. Dose-response relationship for the effect of l MCe on the lung and other organs after inhalation of labeled fused aluminosilicate particles (as of September, 1978)...

Clearance to pulmonary lymph nodes will occur at a fractional rate of 0.0001 per day. Dissolution of the deposited particles and absorption of cerium into the systemic circulation will occur at rates that are between the extremes represented by CeCh in CsCl particles and Ce oxide or Ce in fused aluminosilicate particles as given by the functions included in Figure 9. These rates should not be expected to be constant over the entire clearance period and will depend upon the overall composition of the bulk aerosol particles, which indude particle size, amount of stable lanthanide present, acidity, and the solubility of other components of the particles. The accuracy of predicting respiratory tract clearance and internal organ uptake of radiocerium will depend heavily upon adequate determination of the particle solubility characteristics. 

Boecker, B. B., McClellan, R. O., Hahn, F. F., Hobbs, C. H., Lay, J. C. and Mauderly, J. L. (1975). Toxicity of 144Ce in fused aluminosilicate particles inhaled by immature beagle dogs. IV, page 165 in Inhalation Toxicology Research Institute Annual Report 1974-1975, Report No. LF-52 (Lovelace Foundation, Albuquerque, New Mexico). 

Figure 4. Clearance of 134Cs-fused aluminosilicate particles from lungs of rats exposed to diesel exhaust (Data from ref. 23).

ICRP (1995) considers the experimental data on strontium carbonate and chloride and sulfate to support classification of these compounds as Type F. Data on strontium particulates released from irradiated fuel support their classification as either Type F or M. Data on strontium in fused aluminosilicate particles support a classification as Type S. ICRP (1995) recommends assigning all strontium aerosols to Type M in the absence of specific information supporting an alternative classification. 

Snipes MB, Boecker BB, Hahn FF, et al. 1976. Toxicity of inhaled 90Sr fused aluminosilicate particles in beagle dogs, VII. In Inhalation Toxicology Research Institute, ed. Annual reports of the Inhalation Toxicology Research Institute. Albuquerque, NM Inhalation Toxicology Research Institute, 195-199. 

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