The Chemistry of Eolian Quartz Dust and the Origin of Chert

2018 ◽  
Vol 88 (6) ◽  
pp. 743-752 ◽  
Author(s):  
C. Blaine Cecil ◽  
Bruce S. Hemingway ◽  
Frank T. Dulong
Keyword(s):  
Quartz Dust

EFFECT OF DIFFERENT DOSES OF PREDNISOLONE AND ADRENOCORTICOTROPHIC HORMONE (ACTH) ON LYMPHATIC LUNG CLEARANCE AND ON EXPERIMENTAL SILICOSIS

1970 ◽  
Vol 63 (2) ◽  
pp. 325-337
Author(s):  
Carl-Johan Göthe
Keyword(s):  
Lymph Nodes ◽  
Lymphatic System ◽  
The Body ◽  
Lung Weight ◽  
Lung Clearance ◽  
Dust Transport ◽  
Fine Particulate ◽  
Quartz Dust ◽  
Different Doses ◽  
Stimulation Of

ABSTRACT The effect of three doses of prednisolone and ACTH respectively on the weight of the body, the lungs and the hilar lymph nodes was studied on rats killed one month after the intratracheal (i.t.) injection of 50 mg of fine-particulate quartz. The prednisolone was administered via the drinking water, and the ACTH was injected intraperitoneally during the period between the i.t. injection of quartz dust and the killing of the animals. Prednisolone causes the rats to become cachectic and reduces the weight of the hilar lymph nodes. It also retards the transport of quartz dust from the lungs via the lymphatics. All these effects increase with increasing doses of prednisolone. However, its effect on the lung weight is insignificant. ACTH does not affect the body weight, but retards the weight increase of the lungs and the hilar lymph nodes. These effects increase with increasing doses of ACTH, and seem to be connected with an ability of ACTH to promote the clearance of quartz dust from the lungs and hilar lymph nodes. The method used, however, does not make it possible to differentiate quantitatively between any ACTH effects on the bronchogenie and lymphatic lung-clearance mechanisms. Available data, however, indicate that the stimulation of the dust transport from the lungs and hilar lymph nodes is, at least to some extent, related to the lymphatic system.

scholarly journals Complex laboratory investigations in occupational respiratory diseases

2008 ◽  
pp. 26-30
Author(s):  
L. A. Ivanova ◽  
M. N. Gorizontova ◽  
Yu. V. Statsenko ◽  
I. V. Babenko ◽  
G. M. Vologzhanina ◽  
...  
Keyword(s):  
Treatment Strategies ◽  
Bronchial Epithelium ◽  
Point Of View ◽  
Individual Treatment ◽  
Laboratory Examination ◽  
Brush Biopsy ◽  
Cell Dysfunction ◽  
Bronchial Mucus ◽  
Respiratory Pathology ◽  
Quartz Dust

Results of complex laboratory examination of 103 patients with dust related bronchitis caused by exposure of various industrial dusts, 22 patients with pneumoconiosis and 12 subjects not having respiratory pathology and not exposed to quartz dust or any other occupational hazards are presented in this article. Laboratory examination included morphological investigations of sputum and bronchial brush biopsy specimens, cytochemical characterization of bronchial ciliated epithelium and blood cells, and bacteriological and serological investigations of bronchial mucus. Our results demonstrated that morphological lesions of bronchial epithelium cells leading to their death followed cell dysfunction, disorders of enzyme activity, hypoxemia, predominance of Haemophilus influenzae in microflora, and significant inflammatory and allergic response in blood. These changes were found in different clinical stages of dust related bronchitis and pneumoconiosis. The findings obtained are of great importance for understanding pathogenic mechanisms of dust related lung diseases as well as from clinical point of view such as diagnosis and development of individual treatment strategies.

Atomization of Water Sprays for Quartz Dust Control

1988 ◽  
Vol 3 (12) ◽  
pp. 327-331 ◽  
Author(s):  
Natesa I. Jayaraman ◽  
Robert A. Jankowski
Keyword(s):  
Dust Control ◽  
Water Sprays ◽  
Quartz Dust

scholarly journals Aerosols of synthetic amorphous silica do not induce fibrosis in lungs after inhalation: Pathology working group review of histopathological specimens from a subchronic 13-week inhalation toxicity study in rats

2018 ◽  
Vol 2 ◽  
pp. 239784731880527
Author(s):  
Klaus Weber ◽  
Axel Bosch ◽  
Mario Bühler ◽  
Chirukandath Gopinath ◽  
Jerry F Hardisty ◽  
...  
Keyword(s):  
Amorphous Silica ◽  
Working Group ◽  
Recovery Period ◽  
Toxicity Study ◽  
Inhalation Toxicity ◽  
Synthetic Amorphous Silica ◽  
Comparative Group ◽  
Quartz Dust ◽  
High Level ◽  
Dose Levels

In a subchronic (13-week) inhalation toxicity study with a terminal sacrifice (after 13 weeks inhalation) and several recovery period sacrifices (13, 26, 39, and 52 weeks), the effects of AEROSIL® 200 (pyrogenic synthetic amorphous silica (SAS)), AEROSIL® R 974 (surface-treated pyrogenic SAS), and SIPERNAT® 22 S (precipitated SAS) were tested in rats at multiple dose levels. The aforementioned materials are all SAS products. A comparative group of animals was exposed to quartz dust. This study attempts to reexamine the lung tissues originally evaluated in a study published by Reuzel et al. using the current standards. To reach a high level of credibility, the results of the reevaluation were subsequently examined by a pathology working group (PWG). In particular, the reevaluating pathologist and the PWG concluded that, even though quartz (crystalline silica) persisted, induced alterations in the lungs following 13 weeks of exposure to amorphous silicas were reversible following 52 weeks of recovery. A long-term adversity has not been established with SAS products. However, quartz dust damages lungs significantly by causing pulmonary fibrosis.

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