Modeling the Long-Term Retention of Plutonium in the Human Respiratory Tract Using Scar-Tissue Compartments

Poudel, Deepesh; Avtandilashvili, Maia; Klumpp, John; Bertelli, Luiz; Tolmachev, Sergei Y.

doi:10.1093/rpd/ncab142

Cited by 3 publications

(1 citation statement)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The risk of cancer to the respiratory tract depends on the effective dose to the lungs, and the risk is greater when the plutonium is cleared more slowly (ICRP 2019). However, the specific activity of plutonium is high enough that some inhaled particles may influence their own biokinetics via irradiation of surrounding tissues (Poudel et al 2021a). There is evidence that plutonium may result in the formation of scar tissue in the respiratory tract even at low doses (Poudel et al 2021b), and plutonium-induced lung fibrosis (PuLF) has also been observed in individuals with doses to the respiratory tract as small as 10 Sv (0.5 Gy) (Newman et al 2005).…”

Section: Introductionmentioning

confidence: 99%

Localized Instantaneous Dose Rates from Inhaled Particles of 239Pu

2022

Self Cite

View full text Add to dashboard Cite

In this work, the authors present instantaneous local dose rates from particles of plutonium-239 oxide ( 239 PuO) embedded in various regions of the respiratory tract. For comparison, a small number of simulations were performed in a representative region of the respiratory tract with other chemical compounds including pure metallic 239 Pu, 239 PuO 2 , 239 PuO 3 , 239 Pu 2 O 3 , and 239 Pu(NO 3 ) 4 . A small number of simulations were also performed with 238 PuO, weapons grade Pu, and Pu from a typical radioisotope thermoelectric generator (RTG) source for the same reason. The self-shielding effect is minor for very small particles but gradually becomes more significant as the particle size increases. For particles that are 0.1 mm and larger (excluding Pu nitrate), the calculated dose rate within several microns of the particle may be sufficient to damage lung cells, but the implications of damage to such a small volume of tissue are unclear. However, it is reasonable to assume that clinical effects will be observed if a large enough volume of tissue is damaged, as might happen when large numbers of particles are inhaled. The instantaneous dose rate around a particle may be predictive of deterministic effects, scar tissue formation, and biokinetics.

show abstract

Section: Introductionmentioning

confidence: 99%

Localized Instantaneous Dose Rates from Inhaled Particles of 239Pu

2022

Self Cite

View full text Add to dashboard Cite

show abstract

Forty-eight-year follow-up of a female worker exposed to highly enriched uranium via chronic and acute inhalation

Avtandilashvili,

Tolmachev

2024

Radiat Environ Biophys

View full text Add to dashboard Cite

Modified human respiratory tract model to describe the retention of plutonium in scar tissues

Poudel,

Avtandilashvili,

Klumpp

et al. 2023

Radiation Protection Dosimetry

View full text Add to dashboard Cite

The Human Respiratory Tract Model described in Publication 130 of the International Commission on Radiological Protection provides some mechanisms to account for retention of material that can be subject to little to no mechanical transport or absorption into the blood. One of these mechanisms is ‘binding’, which refers to a process by which a fraction (‘bound fraction’) of the dissolved material chemically binds to the tissue of the airway wall. The value of the bound fraction can have a significant impact on the radiation doses imparted to different parts of the respiratory tract. To properly evaluate—and quantify—bound fraction for an element, one would need information on long-term retention of the element in individual compartments of the respiratory tract. Such data on regional retention of plutonium in the respiratory tract of four workers—who had inhaled materials with solubility ranging from soluble nitrate to very insoluble high-fired oxides—were obtained at the United States Transuranium and Uranium Registries. An assumption of bound fraction alone was found to be inconsistent with this dataset and also with a review of the literature. Several studies show evidence of retention of a large amount of Pu activity in the scar tissues of humans and experimental animals, and accordingly, a model structure with scar-tissue compartments was proposed. The transfer rates to these compartments were determined using Markov Chain Monte Carlo analysis of the bioassay and post-mortem data, considering the uncertainties associated with deposition, dissolution and particle clearance parameters. The models predicted that a significant amount—between 20 and 100% for the cases analyzed—of plutonium retained in the respiratory tract was sequestered in the scar tissues. Unlike chemically-bound Pu that irradiates sensitive epithelial cells, Pu in scar tissues may not be dosimetrically significant because the scar tissues absorb most, if not all, of the energy from alpha emissions.

show abstract

Modeling the Long-Term Retention of Plutonium in the Human Respiratory Tract Using Scar-Tissue Compartments

Cited by 3 publications

References 47 publications

Localized Instantaneous Dose Rates from Inhaled Particles of 239Pu

Localized Instantaneous Dose Rates from Inhaled Particles of 239Pu

Forty-eight-year follow-up of a female worker exposed to highly enriched uranium via chronic and acute inhalation

Modified human respiratory tract model to describe the retention of plutonium in scar tissues

Contact Info

Product

Resources

About