摘要:

The effects of the application of potassium ferrate to remove possible toxic compounds are presented. Potassium ferrate (K2FeO4) is shown in this work to be an effective means to remove toxic metals and nonmetals from aqueous solution. The toxic material present in water is precipitated from aqueous solution and readily removed. Potassium ferrate removes itself from solution. Discolored contaminated water may be made clear by utilizing potassium ferrate. In addition, turbidities of solutions induced by dissolved substances are eliminated by the action of potassium ferrate. The efficacy of potassium ferrate in cleaning contaminated water shows great potential in application to municipal and industrial waste water.

ISSN:0098-4108    

DOI:10.1080/15287399209531611

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

A rat model for combined exposure to cadmium and nickel is presented that involves the administration of drinking water containing these elements over a period of 90 d. Coadministration of these two ions in drinking water leads to brain levels of both elements that are significantly higher than results from the administration of equal doses of the metals individually. The enhanced biliary excretion of cadmium in rats given sodium N‐benzyl‐d‐glucamine dithiocarbamate (BCDTC) is almost twice as great in those animals given cadmium and nickel as in those animals given cadmium only. The excretion of nickel is reduced by the administration of this chelating agent. Although equal amounts of nickel and cadmium were administered to these animals, liver and kidney cadmium levels were approximately 100 times greater than the corresponding nickel levels. The results suggest that combined exposure to these elements may lead to enhanced levels of nickel and cadmium in the brain and a level of nervous system damage not predictable from information obtained under conditions of exposure to only one of these elements.

ISSN:0098-4108    

DOI:10.1080/15287399209531612

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The investigation sought to identify alterations of specific ciliated epithelial surface components after exposure to formaldehyde (HCHO) levels that decrease respiratory ciliary function. Bovine tracheae were reacted with an analog of N‐hydroxysuccinimidobiotin to label epithelial surface‐accessible components before exposure to HCHO. The tracheae were then exposed to 0, 16, 33, and 66 μg HCHO/cm2epithelial surface for 30 min. Cilia were isolated from the epithelium, separated into membrane and internal axonemal portions, analyzed on sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PACE), and either stained to detect proteins or transblotted to detect biotin‐labeled components. Densitometric analysis of axoneme proteins showed a decrease in the total amount extracted with increased HCHO concentration, including axoneme‐specific proteins, dynein, and tubulin. However, biotinylated proteins in the axoneme fractions proportionately increased. Membrane fractions showed little change in protein with increasing HCHO concentration. The majority of these is not biotin‐labeled and thus not surface‐accessible components. Biotinylated material in the membrane fractions showed a significant decrease with increased HCHO concentration, particularly of bands at 92, 98, and 105 kD. These data suggest that increasing HCHO exposure reduces both extractable ciliary axonemes and detergent‐soluble surface components, possibly by stabilizing respiratory epithelial membranes. This process apparently strengthens association of certain surface components with the internal axoneme, thereby reducing subsequent solubilization in detergent.

ISSN:0098-4108    

DOI:10.1080/15287399209531613

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Exposure of cultures of human lung fibroblasts to 0.5 ppm ozone for 20 h resulted in a significant increase in cellular mortality by 29%; after exposure to 2.5 ppm ozone for 4 h, the increase amounted to 74%. A marked difference in sensitivity to ozone was observed between fibroblast lines from different individuals. This variability in resistance to ozone was more evident after exposure to 0.5 ppm ozone for 20 h, when compared with 2.5 ppm ozone for 4 h. In one fibroblast line, synthesis of hyaluronan was enhanced by exposure to 0.5 ppm ozone for 20 h. The concentrations of hyaluronan in culture media increased in experiments using different fibroblast cell lines, a phenomenon that was obvious both if cell numbers and combined protein concentrations of cells and media are selected as references for hyaluronan concentrations.

ISSN:0098-4108    

DOI:10.1080/15287399209531614

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

To investigate how alveolar macrophages adapt themselves to oxidative pollutants in the long term, rats were exposed to a strong oxidant, ozone (O3), or a weak oxidant, nitrogen dioxide (NO2), for a maximum duration of 12 wk. After exposures, alveolar macrophages were collected by pulmonary lavage.

ISSN:0098-4108    

DOI:10.1080/15287399209531615

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

Five cases of poisoning by cypermethrin, a pyrethroid pesticide, are presented. The chemical was inadvertently introduced to the air‐conditioning ducts and the patients inhaled it. Exposed patients experienced shortness of breath, nausea, headaches, and irritability. The exposure was compounded by repeated entry into the contaminated area and slow referral to a physician experienced in pesticide exposures.

ISSN:0098-4108    

DOI:10.1080/15287399209531616

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

摘要:

The objective was to determine percutaneous absorption of chlordane in vitro and in vivo from soil into and through skin. The data are needed to calculate the absorbed dose of chlordane from soil, which is then used to assess the toxicity risk. Chlordane, an insecticide for which residues exist in soil, is restricted currently to use for termite control. Chlordane is highly lipophilic with little or no movement out of soil. Soil (Yolo County 65‐California‐57–8; 26% sand, 26% clay, 48% silt, 0.9% organic) was passed through 10‐, 20‐, and 48‐mesh sieves. Soil then retained by 80‐mesh was mixed with14C‐labeled chemical at 67 ppm. Acetone solutions were prepared for comparative analysis. Human cadaver skin was dermatomed to 500 pm and used in glass diffusion cells with human plasma as the receptor fluid (3 ml/h flow rate) for a 24‐h skin application time. Chlordane concentration within skin from in vitro studies was 0.34 ± 0.31% from soil and 10.8 ± 8.2% from acetone vehicle (p < .01). Individual variation from human skin sources was evident (p < .008). Chlordane accumulation in human plasma receptor fluid was the same for soil (0.04 ± 0.05%) and acetone (0.07% ± 0.06%) formulations. Most of the remaining chlordane was recovered in the soap and water skin surface wash. In contrast, in vivo percutaneous absorption of chlordane in the rhesus monkey was the same for soil (4.2 ± 1.8%) and acetone (6.0 ± 2.8%) formulations (p = .29, nonsignificant). Multiple soap and water washings were necessary to remove chlordane from skin, suggesting that a single wash may not adequately remove all the chlordane.

ISSN:0098-4108    

DOI:10.1080/15287399209531617

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor

ISSN:0098-4108    

DOI:10.1080/15287399209531610

出版商:Taylor & Francis Group    

年代:1992

数据来源: Taylor