| 1. |
- Akselsson, Roland, et al.
(författare)
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Particle Size Distribution and Human Respiratory Deposition of Trace Metals in Indoor Work Environments
- 1976
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Ingår i: Annals of Occupational Hygiene. - : Oxford University Press (OUP). - 1475-3162. ; 19:3-4, s. 225-238
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Tidskriftsartikel (refereegranskat)abstract
- Respiratory response to inhalation of fine particles has been investigated for the aerosol generated by welding. Particles were sampled using a pair of 5-stage cascade impactors operating at 1 l./min flow rate. The subject exhaled into one impactor through an air ballast arrangement, and the other impactor simultaneously sampled the surrounding air. Particle size fractions were analyzed for principal elemental constituents from sulphur to lead using proton induced X-ray emission, PIXE. The results indicated a complex respiratory response, including both increase in particle size due to exposure to high humidity in the respiratory tract and deposition of particles during inhalation. The response was found to be different for the element group Mn, Cr, Fe, Ni compared to the group K, Ca, Ti by observing the associations among the elements as a function of particle size in the inhaled and exhaled aerosol. However, for respiratory deposition efficiency alone in all runs averaged together, no systematic differences between the different elements are demonstrated at the 99 % confidence level.
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| 2. |
- Bohgard, Mats, et al.
(författare)
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An Analytical Procedure for Determining Chromium in Samples of Airborne Dust
- 1979
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Ingår i: Annals of Occupational Hygiene. - : Oxford University Press (OUP). - 1475-3162. ; 22:3, s. 241-251
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Tidskriftsartikel (refereegranskat)abstract
- Abstract in UndeterminedA method is described for assessing occupational exposures to chromium aerosols; it involves four procedures. The first, proton induced X-ray emission (PIXE), measures the total chromium,. The second, electron spectroscopy for chemical analysis (ESCA), measures the oxidation state of the particle surfaces, and the third, which uses sym-diphenylcarbazide (DPC), measures the proportion of water-soluble chromium VI. The fourth, transmission electron microscopy (TEM), provides information about the size and shape of the particles and guides the interpretation of the ESCA-data.The multielemental nature of PIXE-analysis is advantageous in eliminating the possibility of interference in the DPC-method and in eliminating chromium compounds from the tentative list of existing health hazards in the smoke. These methods were applied to the analysis of samples of fume produced in welding, and information was obtained for the amounts of soluble and insoluble chromium (III and VI) in samples of different aerosols.
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