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Exposure to diesel exhaust fumes in the context of exposure to ultrafine particles

100%

Bujak-Pietrek S., Mikołajczyk U., Kamińska I., Cieślak M., Szadkowska-Stańczyk I.

International Journal of Occupational Medicine and Environmental Health

2016

vol. 29

issue 4

667-682

Objectives Diesel exhaust fumes emission is a significant source of ultrafine particles, the size of which is expressed in nanometers. People occupationally exposed to diesel exhaust particles include mainly workers servicing vehicles with engines of this type. This article presents the analysis of measurements of ultrafine particle concentrations occurring in the bus depot premises during the work connected with everyday technical servicing of buses. Material and Methods The measurements were carried out in the everyday servicing (ES) room of the bus depot before, during and after the work connected with bus servicing. Determinations included: particle concentrations in terms of particle number and particle surface area, and mass concentrations of aerosol. Results Mean value of number concentration of 10- to 1000-nm particles increased almost 20-fold, from 7600 particles/cm³ before starting bus servicing procedures to 130 000 particles/cm³ during the bus servicing procedures in the room. During the procedures, the mean surface area concentration of particles potentially deposited in the alveolar (A) region was almost 3 times higher than that of the particles depositing in the tracheo-bronchial (TB) region: 356.46 μm²/cm³ vs. 95.97 μm²/cm³, respectively. The mass concentration of the fraction of particulate matter with aerodynamic diameter 0.02–1 μm (PM₁) increased 5-fold during the analyzed procedures and was 0.042 mg/m³ before, and 0.298 mg/m³ while the procedures continued. Conclusions At the time when bus servicing procedures continued in the ES room, a very high increase in all parameters of the analyzed particles was observed. The diesel exhaust particles exhibit a very high degree of fragmentation and, while their number is very high and their surface area is very large, their mass concentration is relatively low. The above findings confirm that ultrafine particles found in diesel exhaust fumes may be harmful to the health of the exposed people, and to their respiratory tract in particular.

Staroegyptské měděné a bronzové artefakty v Egyptském muzeu Lipské univerzity. Průběžná zpráva o projektu

67%

Odler M., Kmošek J., Jamborová T., Msallamová Š., Kmoníčková M., Šálková K.

Pražské egyptologické studie (Prague Egyptological Studies)

2016

issue 16

37-46

This article presents a preliminary report on the first results of the interdisciplinary project Early copper metallurgy in Ancient Egypt- a case study of the material from Agyptisches Museum - Georg Steindorff - der Universitat Leipzig, in cooperation of the Czech Institute of Egyptology, Faculty of Arts, Charles University in Prague, Institute of Chemistry and Technology in Prague and the Egyptian Museum in Leipzig. The project is focused on the analysis of a selected corpus of artefacts from ancient Egyptian and Nubian sites (fig. 1 ). The analysed material was found in greatest part at the Egyptian sites of Abusir, Abydos and Giza and at the Nubian site of Aniba (fig. 2). The artefacts represent an outline of the development of ancient Egyptian metallurgy over more than one and half millennia, from the First Dynasty (ca 3100 - 2900 BC) until almost the end of the New Kingdom (ca 1200 BC). The selected corpus of artefacts has been documented by X-ray radiography and computer tomography last year at the Institute of Mineralogy, Crystallography and Material Science of the Leipzig University. In all, 86 artefacts were then sampled and almost 100 samples obtained. The results of a metallography and SEMIEDS analysis of five selected artefacts, representing five different chronological stages of the corpus, are discussed in this article (Table 1 ). The first one is a Dynasty 1 vessel from Abusir South (AMUL 2162; Fig. 3). This bowl was hammered out of copper sheet, with high contents of Ni, As and Fe. Non-metallic admixtures of copper sulfides are present in the inner structure, which is highly deformed by the hammering. The second is an Old Kingdom vessel from Giza made of arsenical copper, hammered and annealed (AMUL 2169; Figs. 4-5). The third is a lugged and decorated Middle Kingdom axe blade, hammered and annealed and made of copper with admixtures of As, Fe and S (AMUL 3952; Fig. 6). The fourth is a pair of tweezers from a C-Group tumulus N83 at Aniba, which was made by the cold hammering of arsenical copper, but with rather surprising amount (1 .0%) of tin (AMUL 4647; Figs. 7-8). The fifth is the middle part of an early Dynasty 18 dagger cast from a tin bronze alloy (AMUL 2153; Figs. 9- 1 0). A poster with the analysis of the XRF results was presented at the 41st International Symposium on Archaeometry at Kalamata (Greece) and received honorable mention from The Society for Archaeological Sciences in the Best Student Poster competition (Kmosek - Odler et a/. 2016). All samples will be submitted to neutron activation analysis, and the selected corpus will be also analysed for lead isotope ratios.

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1 International Journal of Occupational Medicine and Environmental Health

1 Pražské egyptologické studie (Prague Egyptological Studies)

1 Bujak-Pietrek S.

1 Cieślak M.

1 Jamborová T.

1 Kamińska I.

1 Kmoníčková M.

1 Kmošek J.

1 Mikołajczyk U.

1 Msallamová Š.

1 Odler M.

1 Szadkowska-Stańczyk I.

1 Šálková K.

2 2016

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Exposure to diesel exhaust fumes in the context of exposure to ultrafine particles

Staroegyptské měděné a bronzové artefakty v Egyptském muzeu Lipské univerzity. Průběžná zpráva o projektu