摘要:

Airway permeability was studied in groups of male guinea pigs at 2, 8, and 24 h after a 1‐h exposure to 7 ppm ozone or at 2 h after a 1‐h exposure to filtered air (control). Intratracheal administration of 2 mg horseradish peroxidase (HRP) was followed by blood sampling at 5‐min intervals up to 30 min. The rate of appearance of HRP in plasma was significantly higher at 2 and 8 h after ozone exposure than that found in animals examined 2 h after air exposure or 24 h after ozone exposure. A dose of 0.12 mg/kg of subcutaneous histamine given after the 75 min blood sample significantly increased the already elevated permeability seen at 2 h post ozone, but had no effect on animals exposed to filtered air 2 h earlier or to ozone 24 h earlier. No difference was seen in the amount of subcutaneous radiolabeled histamine in the lungs of animals exposed 2 h earlier either to air or to ozone. These data indicate that a short‐term exposure to ozone produced a reversible increase in respiratory epithelial permeability to HRP in guinea pigs. The potentiation of this increased permeability by histamine may be another manifestation of ozone‐induced hyperreactivity.

ISSN:0098-4108    

DOI:10.1080/15287398609530853

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Four groups of 20 guinea pigs were sequentially exposed by inhalation to either air followed by sulfuric acid aerosol, ozone followed by sulfuric acid aerosol, ozone followed by air, or air followed by air to determine whether ozone preexposure sensitizes guinea pigs to the airway constrictive effects of sulfuric acid aerosol. All first exposures to ozone or air were 2 h in duration; all second exposures to sulfuric acid or air were for 1 h. All ozone and sulfuric acid exposures were 0.8 ppm and 12 mg/m3, respectively. Animals were observed for respiratory distress during exposure, and excised lungs were quantitated for trapped gas and wet/dry ratios. None of the guinea pigs developed dyspnea, and wet/dry ratios were not altered. Ozone significantly (p < 0.05) increased trapped gas volumes, which were 44% (ozone‐acid) to 65% (ozone‐air) greater than in the air‐air group. Trapped gas volume was 23% greater in the ozone‐acid group than in the air‐acid group, but the difference was not statistically significant (p < 0.20). Thus, ozone increased gas trapping but did not significantly sensitize guinea pigs to the bronchoconstrictive action of sulfuric acid.

ISSN:0098-4108    

DOI:10.1080/15287398609530854

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The effects of fume particles given off by the manual metal arc (MMA) and metal inert gas (MIG) welding of stainless steel (SS) and mild steel (MS) were studied on rat alveolar macrophage cultures in vitro. The fumes were generated by welding, and particulate material obtained was collected on membrane filters. The macrophage cultures were exposed to the total dust and to its water‐insoluble fractions. Cell viability and the release of both lactate dehydrogenase and one lysosomal enzyme from the cells to the medium were measured after an exposure period of 24 h. The cyto‐toxic control dust was DQ 12 quartz, and the inert control dust was pure titanium dioxide. According to the parameters studied, SS/MMA and MSIMMA welding fumes were cytotoxic to rat alveolar macrophages. The cytotoxic effect of SS/MMA welding fumes decreased after the samples had been washed with phosphate‐buffered salt solution. The MIC welding fumes of SS and MS had markedly smaller effects on the cells. Diluted solutions of potassium chromate were also tested in order to investigate its role in the cytotoxicity of SS/MMA welding fumes. The results suggest that hexavalent chromium may be responsible for the cytotoxicity of SS/MMA.

ISSN:0098-4108    

DOI:10.1080/15287398609530855

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Three cases of pulmonary interstitial fibrosis, two in agricultural workers and one in a textile worker, are reported. In lung samples of all three patients the presence of aflatoxin B1was demonstrated by radioimmunoassay (RIA). A possible occupational risk of aflatoxin exposure via the respiratory tract is suggested.

ISSN:0098-4108    

DOI:10.1080/15287398609530856

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

SCOPE 25: APPRAISAL OF TESTS TO PREDICT THE ENVIRONMENTAL BEHAVIOR OF CHEMICALS. Edited by Patrick Sheehan, Friedhelm Korte, Werner Klein, and Philippe Bourdeau, John Wiley and Sons, New York, New York, 1985, 380 pp. $59.95.

ISSN:0098-4108    

DOI:10.1080/15287398609530857

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

ISSN:0098-4108    

DOI:10.1080/15287398609530842

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor