Comparative Dosimetry of Radon in Mines and Homes

Comparative Dosimetry of Radon in Mines and Homes
Author: National Research Council
Publisher: National Academies Press
Total Pages: 257
Release: 1991-02-01
Genre: Medical
ISBN: 0309044847

Studies of underground miners have provided a wealth of data about the risk of lung cancer from exposure to radon's progeny elements, but the application of the miner data to the home environment is not straightforward. In Comparative Dosimetry of Radon in Mines and Homes, an expert committee uses a new dosimetric model to extrapolate to the home environment the risk relationships found in the miner studies. Important new scaling factors are developed for applying risk estimates based on miner data to men, women, and children in domestic environments. The book includes discussions of radon dosimetry and the uncertainties concerning other risk factors such as age and smoking habits. The book also contains a thorough technical discussion of the characteristics of radioactive aerosols in domestic environments, the dose of inhaled radon progeny to different age groups, identification of respiratory tract cells at the greatest risk of carcinogenesis, and a complete description of the new lung dose model being developed by the International Commission on Radiological Protection as modified by this committee.

Radioactive Aerosols

Radioactive Aerosols
Author: Constantin Papastefanou
Publisher: Elsevier
Total Pages: 187
Release: 2011-07-28
Genre: Medical
ISBN: 0080555985

Whenever radioactivity is released to the atmosphere, for example by the detonation of nuclear weapons or the testing of nuclear weapons or from nuclear reactor accidents that fraction of it which remains airborne for more than a few hours is liable to be attached to aerosol particles. The resulting radioactive aerosols are carried by atmospheric mixing processes until they settle out or are scavenged by precipitation. The radiation exposure pathway of maximum concern to humans is by inhalation of aerosols and their deposition in the respiratory tract. In this context, it is important to note that radioactive aerosols are commonly of natural origin alos. In particular, the associated radionuclides can be of natural terrestrial origin, such as the decay products of radon gas, or they can e cosmogenic, such as beryllium-7. The exposure of miners of uranium and other ores and minerals to radon and its aerosol-borne decay products is of major significance. The book describes the formation of aerosols, their aerodynamic size distribution, their atmospheric residence time, their sampling and measurement, the range of radioactive aerosols found and studied thus far, including man-made nuclides and radon decay products and their interaction with man, including deposition in the lung and subsequent health effects. Advanced level science handbook for researchers, scientists and academics Covers all aspects of radiation exposure in humans, including subsequent health implications Presents the latest findings and analysis in this highly topical area

Characteristics of Attached Radon-222 Daughters Under Both Laboratory and Underground Uranium-mine Environments

Characteristics of Attached Radon-222 Daughters Under Both Laboratory and Underground Uranium-mine Environments
Author:
Publisher:
Total Pages:
Release: 1981
Genre:
ISBN:

The organic, inorganic, and radiological characteristics of airborne aerosols have been measured as a function of particle size in controlled atmosphere test chambers and operating uranium mines. Concentrations of benzo(a)pyrene in two mines ranged from 26 to 57 ng/m3 of air. The carbon chain length of adsorbed n-alkanes was correlated with particle size. Normal mining activities produced an ore dust aerosol with mass median aerodynamic diameter (MMAD) greater than 2 .mu.m. The elements Na, Al, Si, K, Ca, Ti, V, Fe, and U exhibited elemental ratios similar to bulk ore and had comparable MMAD's. The S, Zn, and Pb were higher in aerosols than bulk ore and were associated with smaller MMAD particulates. Radon daughter particle size distributions were influenced by the kinds of particulates generated in mining activity.

Cobalt and Nickel Removal from Zinc Sulfate Electrolyte by Solvent Extraction and Precipitation Techniques

Cobalt and Nickel Removal from Zinc Sulfate Electrolyte by Solvent Extraction and Precipitation Techniques
Author: Richard G. Sandberg
Publisher:
Total Pages: 500
Release: 1978
Genre: Air
ISBN:

Sphalerite concentrates prepared during processing of Missouri lead ores contain small percentages of cobalt and nickel which adversely affect zinc electrolysis. The Bureau of Mines has evaluated solvent extraction and precipitation techniques to remove and recover cobalt and nickel from zinc sulfate solution prior to zinc electrolysis. Prepared zinc sulfate solutions containing about 190 gpl of zinc and 50 ppm of both cobalt and nickel were treated using various combinations of complexing reagents, solvent, pH, concentration, time, and temperature. The following complex reagents gave the best results a-nitroso-ßnaphthol, ß-nitrosos-a-napthol, 1,2 cyclohexane dione dioxime (nioxime), di-2-pyridyl ketone oxime, and dimethglyoxime. These reagents in suitable solvents lowered the cobalt and nickel levels to