["Microbial air pollutants--methods for detection of endotoxins, mycotoxins and MVOC"]. / "Mikrobielle Luftverunreinigungen--Verfahren zur Erfassung und Diagnose von Endotoxinen, Mykotoxinen und MVOC"

In the context of microbial emissions from composting facilities the methods for the detection and identification of the groups of substances released, i.e. endotoxins, mycotoxins and Microbial Volatile Compounds (MVOC) are discussed. With the aid of an overview of the different methods employed for the investigation of the single groups of compounds the current state of the art in this field is presented. In conclusion the enormous research needs, especially with regard to the mycotoxins and MVOC, are pointed out.

[Detection of airborne cultivatable microorganisms from compost sites--emissions and imissions]. / Erfassung von luftgetragenen kultivierbaren Mikroorganismen aus Kompostierungsanlagen--Emission und Immission.

The statement presented here gives an overview and assessment of the procedures and concepts currently used for the collection and determination of airborne, culturable microorganisms at sources of emission within composting plants and in their near vicinity. The paper focuses on "classical" methods, which involve cultivation as an intermediate step for the determination of viable, airborne microorganisms. The theoretical and practical requirements on such methods are discussed. Results and experiences from recent investigations are described.

[Measuring the spread of airborne microorganisms in the area of composting sites]. / Messungen zur Ausbreitung von luftgetragenen Mikroorganismen im Umfeld von Kompostierungsanlagen.

Emission concentrations of culturable microorganisms were determined in the vicinity of three open or partly encapsulated composting facilities. Sampling was performed during so-called worst case situations which should promote aerial transport of emissions. Suitability of thermophilic organisms to detect an emitting influence of the plant was confirmed. Generally, concentrations decreased significantly with increasing distances from the plant at all three locations. At one plant 10(6) CFU m-3 thermophilic actinomycetes were found in a distance of 200 m. Partly increased concentrations could be determined even in distances above 500 m. Concentrations could vary within one hour to more than ten times.

[Claims of machine decontamination of dishes under hygienic conditions and of a small load in sewage--a contradiction?]. / Forderungen an die maschinelle Dekontamination von Geschirr unter hygienischen Gesichtspunkten sowie an eine geringe Belastung der Abwässer--ein Widerspruch?

To make sure, whether the hygienic requirements and the ecotoxicologic ones are excluding each other or not, several studies in dishwashing machines under practical conditions have been done. The requirements from the hygienic point of view have been fixed at a 5 lg--reduction of E. faecium ATCC 6057 in a mixture of bovine albumin, mucin and starch as interfering substances on well defined test items. The temperatures in the machine have been increased from around 50 degrees C to 60 degrees C-63 degrees C and a separate precleaning zone has been installed. Under these conditions a cleaner without any available chlorine could be used and that in a lower concentration as before. Furthermore a significant reduction in the parameter AOX and an improvement of the data H 17 and COD could be achieved at the waste water outlet of the machine and at the waste pipe of the whole kitchen without any reduction of the hygienic demands.

[Water disinfection of dental treatment units using ozone]. / Wasserdesinfektion zahnärztlicher Behandlungseinheiten durch Ozon.

The disinfecting effect of ozonized water has been investigated. Under the precondition that the dental chair had been thoroughly sanitized, the system showed a good disinfecting effect. Finally, for reasons of practical medical treatment, the ozone concentration in air and, for reasons of hygiene in drinking water, the ozone concentrations in water were determined under various conditions. In addition, the influence of continuous-flow water heaters is discussed. The problem of continuous-flow water heaters regarding their effects on the colonisation of water by microbes proves not to be significant. The exposure of patients to disinfectants is discussed.

Cytotoxicity and carcinogenicity of chrysotile fibres from asbestos-cement products.

Fibres from weathered asbestos-cement products have little or no haemolytic activity, as compared with UICC chrysotile; this is probably the result of magnesium leaching during the weathering process. Weathered samples of asbestos cement are cytotoxic, but the release of lactic dehydrogenase (LDH) by guinea-pig alveolar macrophages caused by low and intermediate dust concentrations of UICC chrysotile is greater than that of such samples. The influence of serum is different as between UICC chrysotile and asbestos cement. In the former, LDH release by macrophages is enhanced, whereas it is reduced in the latter. Cytotoxicity is length-dependent in respect of LDH release from macrophages and proliferating cells, as well as cell proliferation. In all test systems, the sample from the unweathered core of an asbestos-cement plate is less toxic; only in the haemolysis system using an unbuffered solution can erythrocyte destruction be observed. This may be because this sample contains fewer single fibres than the others and because the specific surface of those fibres is smaller. The carcinogenicity of the weathered asbestos-cement chrysotile fibres is comparable to that of standard chrysotile fibres following intraperitoneal (i.p.) application.

[Hygienic relations and stability of drugs in peridural long-term infusion with implanted or external pumps]. / Hygieniche Verhältnisse und Stabilität der Medikamente bei periduraler Langzeit-Infusion mit implantierten oder externen Pumpen.

Implantable devices (implanted pump/implanted catheter and port) are recommended for continuous epidural application of opiates or local anaesthetics in order to reduce hygienic problems during long term epidural medication. No signs of contamination could be found during bacteriologic culture of residual volumes of 30 patients treated with epidural drug delivery systems and of samples collected during an in vitro investigation (incubation of filled external pump systems at body temperature/storage of syringes with a premixed solution of opiate and local anaesthetic for repeated epidural bolus application). As demonstrated in a case report prophylactic antibiotic coverage prior to implantation may be necessary in patients with a preexisting susceptibility to infection. The concentrations of morphine (radioimmuno-assay) and of bupivacaine (gas-solid chromatography) within the reservoir were stable during clinical therapy as well as during the in vitro experiments.

Macrophage functions after exposure to mineral fibers.

UICC, other well-defined asbestos samples and different man-made mineral fibers (MMM) such as glass fiber and synthetic amphibole asbestos were studied in vitro by using rat and guinea pig lung macrophages. These samples had relatively narrow length and diameter spectra. Most of the fiber samples were added to the cultures on a gravimetric basis, although some were added on a numerical basis. Electrocorundum and DQ12 (Dorentruper Quartz) were used as controls at comparable gravimetrical concentrations. The assays used were the release of lactate dehydrogenase (to demonstrate plasma membrane permeability) and the release of beta-glucuronidase (to indicate lysosomal permeability). Carbohydrate metabolism was monitored by the measurement of lactic acid production and, as one of the tests for macrophage function, the production of lysozyme was determined. The phagocytic ability of the cells was measured, after the addition of opsonized zymosan, by bioluminescence following luminol enhancement. Only some results could be evaluated, however, due to technical difficulties. A length- and dose-dependent cytotoxicity of the fibers was found in this system which was similar to that previously described with permanent cell lines. No great differences were found between fibers having different physicochemical compositions if their geometric dimensions were similar. Long, very thin fibers of glass, chrysotile, crocidolite and synthetic fluoroamphiboles were all toxic in the test system.

Influence of well-defined mineral fibers on proliferating cells.

The effects of well-defined asbestos and man-made mineral fibers, as well as glass and synthetic fluoroamphibole, on phagocytizing permanent rat tumor cells were tested. The following parameters were compared: cell proliferation as determined by cell count and 3H-thymidine incorporation, RNA synthesis by 3H-uridine uptake, protein synthesis by incorporation of 3H-labeled amino acids, protein content and plasma membrane permeability by release of lactic dehydrogenase. The dosage of most of the dusts was estimated gravimetrically, but for some dusts also numerically. Because of the wide range of different fibers lengths, diameters and specific weights, it was sometimes difficult to compare chemically and physically differing fiber fractions with the same fiber counts. In some cases, resulting weights are so different that a direct comparison of the conclusions is impossible. The results with fibers of diverse sources showed the same trends: the toxicity of fibers increases with increasing length and dose. In this test system we found an inhibition of DNA and RNA synthesis. Protein synthesis as measured by amino acid uptake per total cell culture decreased, but the protein content of the single cell increased as determined by the Lowry method. The increase of plasma membrane permeability as determined by lactic dehydrogenase was also dependent on fiber length and concentration. Generally the thinner the fiber, the greater the toxicity when gravimetrical dosage and the same length distributions are employed. Beyond that we can state that the toxicity of fibers from different sources with similar fiber dimensions is similar. One of the glass fiber fractions has a comparable geometry (length, diameter) to the UICC fraction of chrysotile and exhibits the same high toxicity.

Macrophage functions after exposure to nonfibrous mineral dusts.

The effects of the standard dusts, electrocorundum, and Dorentruper quartz (DQ12), as well as mine dusts have been tested in guinea pig lung macrophage cultures. The parameters compared were: release of lactic dehydrogenase for demonstration of plasma membrane permeability and production of lactic acid as an indicator of carbohydrate metabolism. In addition to the dose-dependent toxicity of different mine, coal and other mineral dusts, we studied the influence of cell culture media and the supplement of fetal calf serum (FCS) and bovine serum albumin (BSA) upon the cell toxicity in this test system. We demonstrated a protective effect of FCS and BSA on dusts of low and medium toxicity, while dusts of high toxicity, like DQ12, were not influenced in their toxicity.

Reaction of cells cultured in vitro to different asbestos dusts of equal surface area but different fibre length.

Peritoneal macrophages from mice were cultured in Leighton tubes and exposed to UICC chrysotile, crocidolite or amosite. Their cytotoxicity (Erythrosin uptake), release of lactate dehydrogenase (LDH) and uptake of 3H amino acids were determined according to weight (100 micrograms/tube), surface area (21.3 cm2 or fibre length. In all reactions tested chrysotile was more active than the amphiboles, but the latter gained activity if applied according to surface area. Uptake of 3H amino acids basis. Long-fibred asbestos dusts proved more cytotoxic than the corresponding short fibres when used on the basis of equal mass. In experiments with ascites tumour cells induced by nemalite the different asbestos dusts showed a very significant reduction of 3H-labelled thymidine uptake, but on weight basis the amphibole uptake was markedly higher.

Comparison of length-dependent cytotoxicity of inhalable asbestos and man-made mineral fibres.

Fibres of various defined length distributions were tested in vitro and in vivo. Tumour cells with phagocytic ability were used as the in vitro test system. DNA and protein synthesis and cell proliferation and enzyme release (LDH) were determined. Using gravimetrical and numerical doses in cultures, good indications of the toxicity of single fibres were found. It was possible to demonstrate clear-cut relationships between fibre length and cytotoxicity. In this test system, the toxicity of fibres increases with increasing length. The results of the cell experiments also furnish important indications of the doses of fibrous dusts to be used in animal tests and of the possibility of comparing different fibres with each other, especially with respect to the numerical or gravimetrical quantification of fibre fractions. Amosite, chrysotile, crocidolite and glass fibres of three or four different length spectra were tested.