Inhaled /sup 147/Pm and/or total-body gamma radiation: Early mortality and morbidity in rats

Abstract

Rats were given doses of 6OCo gamma radiation and/or lung burdens of 147Pm (in fused aluminosilicate particles) within lethal ranges in an experiment t o determine and compare morbidity and mortality responses for the radiation insults within 1 year after exposure. Radiation-induced morbidity was assessed by measuring changes in body weights, hematologic parameters, and pulmonary-function parameters. Acute mortality and morbidity from inhaled promethium were caused primarily by radiation pneumonitis and pulmonary fibrosis that occurred more than 53 days after exposure. Acute mortality and morbidity from total-body gamma irradiation occurred within 30 days of exposure and resulted from the bone-marrow radiation syndrome. The hazard function model, proposed by Scott e t al. (1989), applied to the data from rats exposed either t o promethium aerosols or total-body gamma radiation predicted the LD50/365 lung doses for rats exposed to combined radiation insults.

Calculating Hematopoietic-Mode-Lethality Risk Avoidance Associated with Radionuclide Decorporation Countermeasures Related to a Radiological Terrorism Incident

“…These increments are added (via integration). This normalized dose increment approach to evaluating the risk of a specific deterministic effect (e.g., lethality via the hematopoietic or pulmonary mode) has been validated by laboratory animal studies designed specifically for HF model testing (Scott et al 1987, 1989; Filipy et al 1989). This includes studies involving inhalation exposure to insoluble aerosols that contained mixtures of alpha and beta emitting radionuclides (Scott et al 1990).…”