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Microbiological air contamination in premises of the primary health-care

Karwowska E., Miaśkiewicz-Pęska E., Andrzejewska-Morzuch D

Archives of Environmental Protection

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2013

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Vol. 39, no. 4

51--58

EN

The aim of this research was to evaluate the microbiological indoor air contamination level in chosen facilities of the primary health-care for adults and children. The total numbers of mesophilic bacteria, staphylococci, coli-group bacteria and moulds in both surgery rooms and patients’ waiting rooms were determined. Air samples were collected with a MAS 100 impactor and the concentration of microorganisms was estimated by a culture method. The microbiological air contamination level was diverse: the number of mesophilic bacteria ranged from 320 to 560 CFU/m3, number of staphylococci – 10–305 CFU/m3, coli group bacteria – 0–15 CFU/m3 and moulds – 15–35 CFU/m3. The bacteriological contamination level of the air in examined community health centers was higher than described in the literature for hospitals and exceeded the acceptable values proposed for the surgery objects.

PL

Przedmiotem pracy była analiza liczebności mikroorganizmów w wytypowanych pomieszczeniach służby zdrowia w placówce podstawowej opieki zdrowotnej. Zakres badań obejmował określenie stężenia bakterii mezofilnych, gronkowców, bakterii grupy coli oraz grzybów pleśniowych w powietrzu poczekalni dla chorych, gabinetu lekarskiego oraz punktu szczepień. Próbki pobierano za pomocą aparatu MAS 100 firmy Merck a liczebność mikroorganizmów szacowano metodą hodowlaną. Stwierdzono, iż poziom zanieczyszczenia mikrobiologicznego powietrza badanych pomieszczeń był zróżnicowany. Liczebność bakterii mezofi lnych kształtowała się na poziomie 320–560 JTK/m3, gronkowców – 10–305 JTK/m3, bakterii grupy coli – 0–15 JTK/m3 a grzybów pleśniowych – 15–35 JTK/m3. Poziom zanieczyszczenia bakteriologicznego w badanej placówce opieki zdrowotnej był wyższy niż ten dopuszczalny dla pomieszczeń szpitalnych w tym sal operacyjnych.

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Wpływ temperatury, intensywności mieszania oraz napowietrzania na efektywność procesu bioługowania metali z wybranych odpadów przemysłowych

Andrzejewska-Morzuch D, Karwowska E.

Rocznik Ochrona Środowiska

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2012

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Tom 14

623--631

EN

In the research work the influence of temperature, mixing intensity and aeration on heavy metals release from two types of industrial heavy metal containing wastes - combustion ash and galvanic waste - was analyzed. The bioleaching process was carried out using the culture based on the activated sludge as a source of active, sulphur-oxidizing microflora. The presence of Acidithiobacillus thiooxidans bacteria was proved using PCR technique. The culture was initially adapted to the growth in presence of 1% sulphur, up to the moment it achieved pH 1-2. The experiment was carried out in four variants, with different process parameters: temperature 22 degrees C, mixing 125 rpm, without aeration; temperature 22 degrees C, mixing 50 rpm, without aeration; temperature 37 degrees C, mixing 125 rpm, without aeration; temperature 22 degrees C, mixed and aerated with compressed air. After 14 days the amount of heavy metals released from the wastes was determined using ASA method to evaluate the process effectiveness in different experimental conditions. Mean value, standard deviation and variation coefficient was calculated. The effectiveness of heavy metals removal from the ash was significantly higher than the galvanic sludge bioleaching, in which only cadmium and chromium was effectively released (with the average effectiveness of 14.8-47.8% of Cd and 12.5-90,6% of Cr, depending on the experimental variant). In case of the combustion ash, the average removal efficiencies were: 1.1-22% of Zn, 04-12.3% of Cu, 2.8-19.7% of Pb, 3.4-6.7% of Cd, 2.8-52.2% of Ni and 43.8-87.4% of Cr, depending on process parameters. The increase of temperature from 22 to 37 degrees C resulted in the increased effectiveness of almost all metals from both tested wastes. Cadmium was the only metal that was leached better in 22 degrees C. In case of galvanic waste, Cd was released more effectively in cultures with mixing intensity of 125 rpm, and in the culture without aeration, while the aeration was favorable to Cr release. For the ash the additional aeration increased the removal of Cu, Cd, Ni and Cr. Copper, lead, nickel and chromium were released effectively using the 50 rpm mixing but zinc - in 125 rpm. The influence of the mixing intensity on cadmium bioleaching from the ash was not observed. The research indicated that the influence of tested parameters depended on the type of the waste as well as the kind of the metal. It is probably influenced by the other factors like the form of the metal in the waste, that should be a subject of further investigations.

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Bioługowanie metali ciężkich z odpadów pogalwanicznych przy neutralnym pH środowiska, w obecności bakterii produkujących biosurfaktanty

Karwowska E., Andrzejewska-Morzuch D

Rocznik Ochrona Środowiska

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2012

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Tom 14

597--606

EN

Precipitates and sludges from the galvanic industry are one of the sources of the environment contamination with heavy metals. Therefore, the investigations are carried out in order to developer the effective method of metals elimination from these wastes. The promising results are obtained in case of the application of microbial leaching. Up to now results concerned mainly the metals bioleaching in acidic environment. In this research work the possibility of heavy metals removal from galvanic wastes using the culture of sulphur oxidizing bacteria (pH 2-4) and a mixed culture of both sulphur oxidizing bacteria and biosurfactant producing bacteria (pH 6.5-8) was examined. It allowed to compare the process effectiveness in acidic and neutral environment. The cultures were prepared based on the activated sludge from the municipal wastewater treatment plant. The presence of sulphur oxidizing bacteria Acidithiobacillus ferrooxidans was confirmed using the PCR method. Bacillus subtilis and B. cereus strains were applied as biosurfactant producers. Three galvanic wastes, different in grain size, water content and heavy metal concentration, were bioleached. The research revealed that the metal release from galvanic wastes was more effective in presence of biosurfactant, especially in case of copper, but also for cadmium and chromium. The process effectiveness in acidic condition was comparatively lower. Zinc was the only metal that was bioleached faster in acidic environment, with similar final metal removal after 25 days of the process. The maximum values of metals elimination in the presence of biosurfactant depended on the bioleached waste type and were: 7.1-100% for copper, 3.7-50.3% for zinc, 30-50.5% for chromium, 34.1-71.9% for cadmium. The effectiveness of the nickel and lead removal was lower than 5%. The prolongation of the bioleaching period up to 40 days in case of waste C (the less susceptible to the bioleaching) resulted in elimination of 67.9% of Cu, 34.7% of Zn, 100% of Cr and 39.1% of Pb, while the effectiveness of nickel removal was still very low.