Zentralblatt fur Bakteriologie, Parasitenkunde, Infektionskrankheiten und Hygiene. Erste Abteilung Originale. Reihe B: Hygiene, praventive Medizin最新文献

Groups of female NMRI-mice inhaled nine weeks 12.4 or 81.8 microgram Pb/m3 24 h per week, while other groups inhaled 0.3 mg NO2 + 5 mg flame soot/m3 or 5 mg NO2 + 0.3 mg flame soot/m3 for 45 h/week. Five animals of each group were randomly selected in weekly intervals and bacterial elimination determined 5 hours after inhaling a Serratia marcescens-aerosol. Bacteria in lung sections were determined by means of the "sandwich-method", using an anti-Serratia-serum and a FITC-loaded antirabbit-gammaglobuline. Inhalation of leadchloride caused a time and dose-dependent deterioration of bacterial elimination, which showed to be statistically significant already after three days of treatment with 81.8 microgram Pb/m3. A time dependent function between bacterial elimination and exposure could not be shown under treatment of the mixed pollutants NO2 and flame soot, although the lung clearance was deteriorated especially in the group treated with 5 mg NO2 + 0.3 mg flame-soot/m3. The experiments give evidence that lead exhibits a cyto-toxic effect on alveolar macrophages while the combined pollutants NO2 and flame-soot exhibit their adverse effect on the mucociliary-system. Nitrogen dioxide is shown to be a more hazardous pollutant than flame-soot within the given combination.

The suitability for field use of heating up to 80 degrees C and adding six different virucidal chemicals for decontamination of drinking and surface water was investigated using the viruses of Polio (vaccine strain), ECBO, Reo, bovine Parvo, HCC, Pseudorabies, ND and Vaccinia. The Parvovirus (concentration 10(5) TCID50/ml) heated to 80 degrees C could not be inactivated completely in drinking water within one hour; the Reovirus could after one hour only at 60 degrees C. The other viruses used lost their infectivity at 56 degrees C within 60 minutes or at 60 degrees C within 20 minutes respectively. Heating therefore seems to be too circumstantial a method for viral decontamination of water and unreliable under field conditions. As to the chemical water additives tested, chloramine-T, hydrogen peroxide and sodium peroxide proved to be unsuitable in spite of virucidal activity. The amount of their concentration necessary for reliable virus inactivation makes the water unfit for drinking. Iodine, a calcium hypochlorite sample and potassium permanganate were useful. Because of its constant reaction in drinking water together with additional advantages, iodination of water would seem to be the best method at present for viral water decontamination usable under field conditions.

The efficacy of hospital hygienic measures was checked in six hospitals. The programme was started by determining the effective state. Subsequently a two-day extension course for the training and instruction of the responsible personnel in charge (physicians, nurses and administrative staff) in the essential problems of hospital hygiene was held. The next measure consisted in giving advice in the preparation of hygiene plans which had to make allowance for the prevailing personal and constructional situation as well as for the hospital equipment. The hygiene plans represented the written concept of the measures to be implemented. Then enquiries, local inspections as well as hygienic-bacteriological ambient analyses were carried out to determine the hygienic situation in the hospital after adoption of the measures and the findings were compared with the situation preceding the initiation of the hygienic programme. The results show that the proposed improvements were mostly realised as far as such administrative measures as the procurement of disinfectant dispensers, throwaway towels and suitable disinfectants were concerned. The instructions given for the implementation of suitable methods of application were complied with to a lesser extent. Moreover, considerable improvements were achieved with regard to the operation and efficiency of the sterilizers. On the whole, the present study demonstrates that suitable measures largely reduce the extensive gaps in information on the part of the staff on hospital hygiene and that the resulting intensification of efforts can greatly contribute towards an improvement of the overall hygiene in hospitals.

We analyzed the cytotoxic effect of a city smog extract from a large urban area, employing mouse macrophages in vitro. In parallel experiments we tested carcinogenic and non carcinogenic polycyclic aromatic hydrocarbons: benzo(a)pyrene, 7, 12-dimethylbenzanthracene, pyrene and anthracene. City smog extract induced a dose-dependent reduction of cell viability and an alteration in cell membrane permeability. In contrast to city smog extract the carcinogenic and non carcinogenic polycyclic aromatic hydrocarbons produced no detectable cytotoxic effects in the dose range we analyzed. Possible implications of the cytotoxic effect of city smog extract on the lung are discussed.

It is bound to use a concentration method for the research of enteroviruses in water. One of the concentration methods, the filtration on alginat membranes, avoids the problem of the virus elution from the filter, then the membrane is soluble in a sodium citrat buffer. This method was studied with different types of water (synthetic water, tap water and wastewater). -The recovery efficiency of Poliovirus I in clear waters (synthetic water and tap water) was poor, unsatisfying reproducible; the results are better for small virus concentrations. This efficiency may be slowly enhanced by the addition to the sample of aluminium chlorid at a final concentration of 5.10(-4) M. -The technical problems (brittleness of the membranes, slow filtrations speed, small sample volume), soon noticeable with clear waters, are more important in the case of trouble waters. Meanwhile the use of this filtration method gives better results for the recovery of Poliovirus I in wastewaters than the direct inoculation to cells cultures.

The observation that PbO2 absorbs besides SO2 other, gaseous pollutants such as HF suggested to extend the lead dioxid cylinder method by means of the fluoride electrode on the determination of the fluoride immission. The results of 656 measurements were used to establish "fluoride-maps" of the federal countries Salzburg and Kärnten.

A new method is described which can be used for the examination of piped drinking water. It is also suitable for monitoring water which was initially of potable quality, and is intended for reuse in the food industry. The method is based on CLARK's "P-A test" and, because this allows many bacterial types to be detected, i.e. Enterobacteriaceae, E. coli, P. aeruginosa, Aeromonadaceae and LANCEFIELD group D streptococci it is called differential hydrobacteriogramme. A preliminary resuscitation treatment to revive sublethally injured cells is essential in this procedure. In earlier work this was attained by adding an equal volume of double strength nutrient broth and later double strength MACCONKEY purple broth, making the method somewhat bulky. In the new procedure, after the resuscitation step, a concentrated bile salts/indicator solution is added, allowing subsequent selective enrichment of the taxa sought. Positive enrichment cultures are examined for these organisms by the procedures summarized in Fig. 1. The new method, when tested on approx. 150 artificially inoculated and 92 natural samples, showed the same productivity and selectivity as the one introduced earlier. The new method is recommended for routine monitoring purposes, because it is less bulky.