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Halophilic microorganisms were traditionally isolated from an aquatic environment. There has been little research conducted into halophiles inhabiting the terrestrial environment in which historic monuments deteriorate. Salt efflorescence deposited on the walls is an observed phenomenon on the surface of historic buildings, and would favour the growth of halophiles. However, some conditions have to be fulfilled in order for efflorescence to occur: (1) the presence of salts, (2) porosity, (3) a source of water. Salt crystallization influences the material structure (cracking, detachment, material loss), but active growth of halophilic microorganisms may be a serious threat to historic materials as well, leading to aesthetical changes such as coloured biofilms, orange to pink or even violet stains. This is why it is important to investigate halophilic microorganisms, taking into consideration both the environmental conditions they need to grow in, material characteristics they inhabit, the mechanisms they possess to cope with osmotic stress, and the methods that should be applied for their identification.

The aim of the study was to compare the content of ergosterol in different microorganisms (bacteria, yeasts and moulds) isolated from the air as well as in six species of moulds in their different morphological forms-live mycelium, dead mycelium, and spores. Evaluation of the level of mould contamination of the air in various places using culture method and ergosterol determination was also performed. The analysis of ergosterol was carried out by gas chromatography equipped with flame ionisation detector. For evaluation of the results, analysis of variance and multiple comparison test were used. The quantity of ergosterol in the spores of various species of mould was in the range 1.9-9.4 pg/spore. The presence of yeasts and bacteria in the air does not significantly affect ergosterol concentration, in view of the low content of that sterol in their cells (max. 0.009 pg/cell for bacteria and 0.39 pg/cell for yeast). An ergosterol concentration above 1 ng per m 3 can be considered an indicator of excessive mould contamination of indoor air. Based on determination of ergosterol in the air of mouldy rooms the result obtained may be compared with the culture method, due to the 1,000 times higher concentration of ergosterol in the mycelium compared with spores. However, in the analysis of outdoor air, in view of the presence of mould mainly in the form of spores and the degradation of ergosterol by UV radiation, analysis of that compound may indicate a lower level of contamination compared with the culture method.

Museums, archives and libraries have large working environments. The goal of this study was to determine microbial contamination in these work places and estimate the influence of microclimatic parameters and total dust content on microbial contamination. In addition, research included evaluation of ergosterol concentration and fungal bioaerosol particle size distribution. Numbers of micro-organisms in the air and on the surfaces in museums were higher (2.1 × 10 2 -7.0 × 10 3  cfu/m 3 and 1.4 × 10 2 -1.7 × 10 4  cfu/100 cm 2 , respectively) than in archives and libraries (3.2 × 10 2 -7.2 × 10 2  cfu/m 3 and 8.4 × 10 2 -8.8 × 10 2  cfu/100 cm 2 , respectively). The numbers of micro-organisms detected in the tested museums, archives and libraries did not exceed occupational exposure limits proposed by Polish Committee for the Highest Permissible Concentrations and Intensities of Noxious Agents at the Workplace. The concentrations of respirable and suspended dust in museum storerooms were 2-4 times higher than the WHO-recommended limits. We found a correlation between microclimatic conditions and numbers of micro-organisms in the air in the tested working environments. In addition, a correlation was also found between ergosterol concentration and the number of fungi in the air. Fungi were the dominant micro-organisms in the working environments tested. Particles within the dominant fractions of culturable fungal aerosols sampled from museum storerooms had aerodynamic diameters between 1.1 and 2.1 µm.

Aerial phototrophs colonize materials of anthropogenic origin, thus contributing to their biodeterioration. Structures preserved at the former Auschwitz II-Birkenau concentration and extermination camp show signs of degradation by cyanobacteria and algae. In order to protect the Auschwitz-Birkenau Memorial Site, diversity of aerial phototrophs growing on the historic buildings has been studied. Analyses of cyanobacterial and algal biofilms growing on various construction substrates were carried out in summer and winter. Multivariate data analyses were used to: characterize the diversity of cyanobacteria and algae growing in brick and wooden camp buildings depending on the research season, indicate preferences of cyanobacteria and algae in colonizing substrates, and to predict the environmental factor that most determines the growth of phototrophs. The biofilms were formed mainly by cyanobacteria, green algae and diatoms. The amount of cyanobacteria and algae in the biofilms was varied, which resulted from changes in climatic conditions, the type of substrate and the height at which the biofilms developed. In the summer, the ratio of cyanobacteria and algae groups was balanced, while in the winter, green algae and diatoms were dominant. Green algae showed a preference for colonizing plaster, wood and concrete, of which the walls and doors of the buildings were made. Their participation was correlated with a height gradient. Cyanobacteria and diatoms grew on bricks and soil on the floor of the buildings and temperature and relative humidity were the factors that modified their amount. Green algae were more cosmopolitan-occurred in dry places, potentially inaccessible to other organisms; therefore, they have been identified as the pioneer group in the prevailing climatic conditions., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Laboratory-scale experiments were conducted using poultry manure (PM) from a laying hen farm. Six strains of bacteria and one strain of yeast, selected on the base of the previous study, were investigated to evaluate their activity in the removal of odorous compounds from poultry manure: pure cultures of Bacillus subtilis subsp. spizizenii LOCK 0272, Bacillus megaterium LOCK 0963, Pseudomonas sp. LOCK 0961, Psychrobacter faecalis LOCK 0965, Leuconostoc mesenteroides LOCK 0964, Streptomyces violaceoruber LOCK 0967, and Candida inconspicua LOCK 0272 were suspended in water solution and applied for PM deodorization. The most active strains in the removal of volatile odorous compounds (ammonia, hydrogen sulfide, dimethylamine, trimethylamine, isobutyric acid) belonged to B. subtilis subsp. spizizenii, L. mesenteroides, C. inconspicua, and P. faecalis. In the next series of experiments, a mixed culture of all tested strains was immobilized on a mineral carrier being a mixture of perlite and bentonite (20:80 by weight). That mixed culture applied for PM deodorization was particularly active against ammonia and hydrogen sulfide, which were removed from the exhaust gas by 20.8% and 17.5%, respectively. The experiments also showed that during deodorization the microorganisms could reduce the concentrations of proteins and amino acids in PM. In particular, the mixed culture was active against cysteine and methionine, which were removed from PM by around 45% within 24 h of deodorization., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Background: The aim of the studies was to determine the level and kind of microbiological contamination of air and surfaces in museum premises with various collection specificities. In addition, the criteria for selecting indicators of contamination with harmful biological agents at museum workposts are proposed., Material and Methods: The analysis of microbial contamination was carried out in 14 museum premises (storehouses, restoration workshops, exhibition hall). Microbiological air purity was measured with a MAS-100 Eco Air Sampler. Surface samples were collected using contact plates RODAC Envirocheck. Biochemical API tests were used to identify bacteria and yeasts. Fungi were diagnosed with taxonomic keys, based on macro- and microscopic mycelia assessment., Results: The levels of microbiological contamination in museums varied and ranged from 2.1 x 10(2) to 7.0 x 10(3) cfu/m3 in the air and from 1.4 x 10(2) to 1.7 x 10(4) cfu/100 cm2 on surfaces. The dominant microorganisms were fungi, which accounted respectively for 18-98% and 23-100% of all isolates from tested sites and surfaces. It was found that the amount of fungi in the indoor air of the Museum of Archeology and Ethnography and the Museum of Independence Traditions equaled respectively 4.2 x 10(2) cfu/m3 and 1.4 x 10(4) cfu/m3, which means that they exceeded the recommended reference value of 2.0 x 10(2) cfu/m3., Conclusions: Having analyzed the frequency of strain isolation, the source of microorganisms and the hazard to human health, 10 fungal species were isolated, which may be regarded as indicators of contamination with harmful biological agents at museum workposts. They are: Aspergillus (A. niger, A. versicolor), Cladosporium (C. herbarum, C. macrocarpum), Penicillium (P. carneum, P. digitatum, P. italicum, P. paneum, P. polonicum), Rhizopus nigricans.

The presented study concerned mycological analysis of buildings in Lódź and evaluation of the role between filamentous fungi contaminated flats and inhabitants health (allergic airway diseases). 49 inhabitants of 20 flats with signs of moulds contamination were examined. Air samples were collected in houses and outdoors. In all inhabitants skin prick tests (SPT) to common allergens and to standardized particular fungal extracts were performed. Moreover, total and serum specific IgE to moulds, rest spirometry were measured in all subjects. Level of moulds contamination in the air of flats was high and in 75% cases exceed accepted limits. The most frequent species isolated from examined rooms were: Penicillium, Cladosporium, Aspergillus, Acremoniu and Alternaria. The most frequent symptoms reported by examined subjects were rhinitis (N = 29, 59.2%), conjunctivitis (N = 29, 59.2%), chronic cough (N = 24, 49%), dyspnea (N = 15, 30.6%) and skin symptoms (N = 24, 49%). Elevated IgE level was found in 12 subjects (24.5%) and in three patients (6.1%) mould specific serum IgE were detected. Nineteen out of all subjects (38.8%) had positive SPT to common allergens (house dust mites, grass and tree pollens). Eight out of these patients (16.3% of the group) were sensitized to moulds (Candida albicans, Alternaria alternata, Botrytis cinerea, Trichophyton mentagrophytes, Helminthosporium halodes, Aspergillus). In all cases sensitisation to moulds was accompanied by allergy to other common allergens. No isolated hypersensitivity to moulds was found. Although the frequency of self-reported symptoms was high, the prevalence of atopy and allergic diseases seems to be similar to that found in general population, but that statement must be confirmed by comparison of the control group.

This paper reviews the most common health effects of exposure to moulds. Allergens of mould may induce rhinitis or bronchial asthma, whereas occupational exposure frequently leads to hypersensitivity pneumonitis. Moulds also reveal cancerogenic and neurotoxic properties. They may cause serious infections, organic dust toxic syndrome and sick building syndrome. Methods used to evaluate exposures and decrease concentrations of spores in the house environment are also presented.