Lung dose

M Dolovich. Lung dose, distribution, and clinical response to therapeutic aerosols. Aerosol Sci Technol 18 230-240, 1993. 

Harley, N.H., and P.S. Pasternack, Experimental Absorption Applied to Lung Dose from Radon Daughters, Health Phys.,23, 771-782, (1972). 

For estimating the lung dose after inhalation by means of models three parameters of air activity are necessary ... 

The risk of lung cancer from exposure to radon daughters in homes is derived by assessing lung dose, either absolutely by evaluating an effective dose equivalent (UNSCEAR, 1982 NEA, 1983) or by scaling the... 

It can be concluded that uncertainties in breathing rate are relatively unimportant in determining lung dose and that dose varies with particle size in much the same manner over the whole physiological range of breathing rates. 

Fisenne, I.M. and N.H. Harley, Lung Dose Estimates from Natural Radioactivity Measured in Urban Air, USAEC Report HASL-TM-74-7 New York, NY (1974). 

However, results obtained from lung dose modelling still show a large range of values for the conversion of Rn-d exposure to dose for the following reasons ... 

Electrostatic precipitators were effective in reducing the radon decay-product concentration below the reference level, but analysis of the room aerosol indicated that the reduction was largely offset by an increase in lung dose per unit exposure. 

Exposure to natural sources of radiation is unavoidable. Externally, individuals receive cosmic rays, terrestrial X-rays, and gamma radiation. Internally, naturally occurring radionuclides of Pb, Po, Bi, Ra, Rn, K, C, H, U, and Th contribute to the natural radiation dose from inhalation and ingestion. Potassium-40 is the most abundant radionuclide in foods and in all tissues. The mean effective human dose equivalent from natural radiations is 2.4 milliSieverts (mSv). This value includes the lung dose from radon daughter products and is about 20% higher than a 1982 estimate that did not take lung dose into account (Table 32.4). 

Aerosol size has an effect on the lung dose. Fine particles breathed through the mouth or the nose from lOOnm to 1,000 nm median size had 5-20 nGy per becquerel. Below 100 nm, this number more than doubled at 25-65 nGy per becquerel at 20 nm median size. Median sizes had an approximate geometric standard deviation of 2, so that the 95% confidence interval of particle sizes ranged from 0.25 to 4 times the stated median size. Very small particles deposited more efficiently in the airways. Lung cancer was related to radiation dose. These dose estimates are important determinants of lung cancer. 

Additional research regarding the health effects of acute-duration inhalation exposure to uranium would be useful these studies should include toxicological end points, lung doses, and metabolic fate. 

Hesterberg TW, Hart GA, Chevalier J, et al. 1998b. The importance of fiber biopersistence and lung dose in determining the chronic inhalation effects of X607, RCFl, and chrysotile asbestos in rats. Toxicol Appl Pharmacol 153 68-82. 

LUDEP (LUng Dose Evaluation Program) was developed concurrently with the new ICRP respiratory tract model. LUDEP was designed principally for two applications ... 

For example, when using a perfusion scan to outline the lung and to correct for tissue attenuation of radioactivity, the total lung dose deposited (TLDrf) is calculated as follows ... 

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