Dust uranium

Haustein and Herrmann (1994) (some of these patients were also reported by Ziegler et al. 1986, Baur 1994, Mehlhorn 1994) 111 SSc, 57 with silicosis Uranium mining (57), coal mining (8), both (12) Silica dust (uranium)... 

Care must be taken in handling radon, as with other radioactive materials. The main hazard is from inhalation of the element and its solid daughters which are collected on dust in the air. Good ventilation should be provided where radium, thorium, or actinium is stored to prevent build-up of the element. Radon build-up is a health consideration in uranium mines. Recently radon build-up in homes has been a concern. Many deaths from lung cancer are caused by radon exposure. In the U.S. it is recommended that remedial action be taken if the air in homes exceeds 4 pCi/1. 

Handling of soluble uranium compounds requires appropriate clothing to prevent skin contact and eye protection to prevent any possible eye contact. Protective clothing requirements for insoluble uranium compounds should prevent repeated or prolonged skin contact. Eye protection for use in handling insoluble uranium compounds should prevent any possibiUty of eye contact. Respirators should always be worn to prevent inhalation of uranium dust, fumes, or gases (38). 

Some cutting fluids, eg, oils, may present a fire ha2ard. Some work materials, eg, magnesium, aluminum, titanium (under certain conditions), and uranium, in finely divided form, also present fire ha2ards. Very small metal chips or dust may ignite. 

The presence of radiation in the workplace - which is an inevitable consequence of the radioactivity of uranium - requires that additional safety precautions be taken over and above those observed in other similar workplaces. There are generally three sources from which radiation exposure may occur (i) radiation emitted from uranium ore in-situ and/or during handling (ii) airborne radiation resulting from the decay of radon gas released from the ore and uranium dust and (iii) contamination by ore dust or concentrate. Radiation levels around uranium mining and milling facilities are quite low - for the most part only a few times the natural background levels - and they decrease rapidly as the distance from... 

Dust created by mining and milling activities blown by the wind from ore stockpiles is a potential source of environmental contamination. The watering of stockpiles or erection of enclosures is resorted to when necessary in order to prevent the spread of dust. Where ventilation systems collect significant amounts of uranium dust in mills, scrubbers are used to remove the dust from the air before it is discharged to the environment. 

Cross,F.T., Palmer,R.F., Filipy,R.E., Busch,R.H. and B.O. Stuart, Study on the Combined Effects of Smoking and Inhalation of Uranium Ore Dust, Radon Daughters and Diesel Oil Exhaust Fumes in Hamsters and Dogs, Pacific Northwest Laboratory Rep. No. PNL-2744> Richland, National Technical Information Service, Springfield, VA., USA (1978). 

Cross, F., Palmer, R., F. and Busch, R., H., Influence of Radon Daughter Exposure Rate and Uranium Ore Dust Concentration on Occurrence of Lung Tumors, in Proc. of the Specialist Meeting on the Assessment of Radon and Radon Daughter Exposure and Related... 

Mehlhorn, J. et al., Analysis for the association between progressive systemic scleroderma, exposure to quartz dust, and silicosis in East German uranium mining, Zbl. Arbeitsmed., 49, 134, 1999. 

Conrad, K. et al., Systemic lupus erythematosus after heavy exposure to quartz dust in uranium mines clinical and serological characteristics, Lupus, 5, 62, 1996. 

The characteristic feature of the uranium exploration industry is the radioactivity of all wastes. The quality of these wastes, such as radon, radioactive aerosols, and dust emitted to the atmosphere, depends on mine production and the radioactive budget in the mines. For example, middle range mine exploring the ores with n x 10 1-10 2% of U content emits to the atmosphere up to 8 x 1010 Bq/day of radon. 

Precipitation inhibitors, dispersants contrasted, 3 686 Precipitation leachate procedure, synthetic, 25 868-869 Precipitation reactions, for niobium and tantalum determination, 27 142-143 Precipitation reagents, protein, 22 133 Precipitation with compressed antisolvent (PCA) process, 24 17, 18 Precipitator dust, in phosphorus manufacture, 19 12 Precipitators, electrostatic, 23 180 Precision agriculture, 23 328 26 269-270 Precision measurement techniques, noble gases in, 27 370 Precision scales, 26 245 Preconcentration, of uranium ores, 25 401 Pre-crosslinked polychloroprene grades, 19 852... 

Occurrence. Important minerals are carnotite K(U02)V04 3/2 H20, more important as a uranium ore, vanadinite Pb5(V04)3Cl and some complex sulphides. It occurs also in certain crude oils and may be recovered from dusts after combustion. 

Of the 313 samples examined, the dust explosion hazards of finely divided aluminium, aluminium-magnesium alloys, magnesium, thorium, titanium and uranium, and the hydrides of thorium and uranium, are rated highest [1]. The... 

Soluble Compounds Animals repeatedly exposed to dusts of soluble uranium compounds in concentrations from 3 to 20mg/m died of pulmonary and renal damage both feeding and percutaneous toxicity studies on animals indicated that the more soluble compounds are the most toxic. In animals, effects on the liver are a consequence of the acidosis and azotemia induced by renal dysfunction. ... 

Leach LJ, Maynard EA, Hodge CH, et al A five-year inhalation study with natural uranium dioxide (UO2) dust. I. Retention and biologic effect in the monkey, dog and rat. Health Phys 18 599-612, 1970... 

Two epidemiology studies have examined mortality among thorium workers neither found significant excess mortality. The standard mortality ratio (SMR) for all causes of death in a cohort of 3039 male workers in a thorium processing plant was 1.05 in comparison to United States white males (Polednak et al. 1983). The estimated radiation levels to the workers for inhalation intake ranged from 0.003-0.192 nCi/m (0.001-0.007 Bq/m ) for a period of 1-33 years. No evidence of overt industrial disease was found in a cohort of 84 workers at a thorium refinery exposed to <0.045-450 nCi/m (<0.002-0.02 Bq/m ) for <1-20 years (Albert et al. 1955). In both studies, the workers were exposed to other toxic compounds (uranium dust) as well as other radioactive materials (thoron, uranium daughters, thorium daughters, cerium). 

After inhalation exposure, the primary route of excretion is in the feces following ciliary clearance from the lungs to the gastrointestinal tract (Wrenn et al. 1981). Fecal excretion may account for as much as 97% of total excretion (Fisher et al. 1983). Higher levels of thorium-230 were excreted in the feces by active crushermen (uranium mill workers exposed to uranium ore dust in the crusher building) compared to retired workers or controls (Fisher et al. 1983). Levels of thorium-230 in the urine were comparable to those of retired workers, and the levels in both were significantly greater than controls. 

Hannibal L. 1982. On the radiological significance of inhaled uranium and thorium ore dust. Health Phys 42 367-371. 

Sill CW. 1977. Simultaneous determination of U-238, U-234, Th-230, Ra-226, and Pb-210 in uranium ores, dusts, and mill tailings. Health Phys 33 393-404. 

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