Cytotoxic fungal spores in the indoor atmosphere of the damp domestic environment

Eight-three fungal isolates collected and cultured from the air spora of damp public sector Scottish housing have been screened for cytotoxic properties. A bioassay procedure has been utilised for this purpose involving cytotoxic effects on human embryonic diploid fibroblast lung cells grown as monolayer cultures within the wells of microtitre plates. The MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] biochemical assay system employed has revealed that 39 (47%) of the moulds investigated possessed spore-associated cytotoxic properties; a value which emphasises the potential health hazards of the continual inhalation of toxigenic fungal propagules by occupants of mouldy houses. Penicillia, the most prevalent fungi found in the internal atmosphere of the domestic environment, accounted for the great majority of cytotoxic strains identified.     

Airborne fungal spores in a sawmill environment in Palakkad District, Kerala, India

Concentration of airborne fungal spores inindoor and outdoor environments of a sawmill in Palakkad district of Kerala, India was studied with Burkard Personal Slide Sampler from January to December 1997. Total spore concentration in the indoor and outdoor showed a 3:2 ratio. Higher spore count was observed in indoor in January and in outdoor in October. Thirty three fungal spore types were identified from the indoor and twenty six from the outdoor. Aspergillus/Penicillium, Cladosporium, Nigrospora, Ganoderma, `other basidiospores' and ascospores were the dominant components of the airspora. Aspergillus/Penicillium, the most dominant spore type in the indoor contributed 51.19% and Cladosporium, the most dominant spore type in the outdoor contributed 44.75% of the total spores. The study revealed high prevalence of predominantly allergenic fungal spores in the sawmill environment.     

Airborne fungal spores in urban and rural environments in Poland

The concentrations of airborne fungal spores were measured during 2001–2002 in two sites in Poland—one in the city and the other in the countryside. The sites differed in habitat characteristics, such as urbanisation level, vegetation and microclimate. The aim of the study was to determine if, and in which way, land use type would affect spore occurrence. The volumetric method was used, and ten easily identifiable spore types were sampled and anyalysed: Alternaria, Botrytis, Cladosporium, Epiccocum, Ganoderma, Pithomyces, Polythrincium, Stemphylium, Torula and Drechslera. The season of spore occurrence was determined using the 90% method. The fungal spores studied were very frequent in the air (in most instances at a frequency higher than 50%). The most common spores were those of Cladosporium, with a frequency range of 83.1–90.5%. In both years the proportion of Cladosporium spores was statistically significantly higher in the city. In both 2001 and 2002 the total seasonal sum of all the spores was higher in the countryside than in the city as was the Seasonal Fungal Index (SFI) values and average concentrations of Botrytis, Ganoderma and Torula. These latter three genera are usually represented as pathogens of plants. The mean spore concentrations of most taxa were significantly higher in the rural environment. Correlation coefficients between daily concentrations at both sites for most of the taxa studied were significant, but with lower correlation values between variables. Such results indicate that the values from the sites are weakly interdependent. The study confirms that land use type may very likely have an impact on the course of spore occurrence, the mean daily concentrations of spores as well as SFI values.     

Airborne fungal spores and the thunderstorm of 24 June 1994

On the evening of 24 June 1994 there were thunderstorms which passed from the south to the north over large areas of England, followed by an extensive and initially alarming episode of 'thunderstorm asthma'. It was eventually concluded that the probable cause of this episode was the release of allergenic particles from wetted grass pollen. As part of the investigation of this episode changes in the fungal air spora were investigated at several sites. The fungal spores present varied from site to site. At London, Addlestone and Leicester there were very marked transient peaks of smut ustilospores (and to a much smaller extent at Cambridge), particularly those of Ustilago segetum (Bull.) Roussel. At many sites there were transient peaks of Cladosporium conidia. The possible causes of the transient peaks are discussed. At most of the other sites except London there were high concentrations of ascospores after the rain. Typically, Didymella ascospores occur after rain, but on this occasion they occurred at low concentrations at all sites, because of dry weather in the previous month. Instead, there were high concentrations of ascospores which normally occur in far lower numbers, viz. ascospores of Phaeosphaeria nigrans and Diatrypaceous ascospores. The reasons for this were related to increased rainfall in the previous thirteen months. There were site to site differences in the ascospore composition of the air spora, and this was related to habitat differences, where this was known. This revised version was published online in June 2006 with corrections to the Cover Date.     

Airborne fungal spores in the coastal plain of Israel: A preliminary survey

Airborne spores were monitored during the years 1993–1995 in three cities along the coastal plain of Israel: Ramat Gan, Tel Aviv (Ramat Aviv) and Haifa. Seasonal fluctuations in the concentration of airborne spores were recorded. The following genera of fungi were identified:Alternaria, Cladosporium, Coprinus, Curvularia, Drechslera. Diplococcum, Epicoccum, Fusarium, Leptosphaeria, Pithomyces, Puccinia, Sphacelotheca, Stemphylium andUstilago. Unidentified spores were very rare and in negligible numbers. The dominant airborne fungal spores wereCladosporium andAlternaria. The monthly variations in airborne spores, observed among the three cities, seem to be rather minor. The recorded levels of airborne spores were below the concentrations that are accepted as threshold levels for provocation of clinical responses.     

Toxic-metabolite-producing bacteria and fungus in an indoor environment.

Toxic-metabolite-emitting microbes were isolated from the indoor environment of a building where the occupant was suffering serious building-related ill-health symptoms. Toxic substances soluble in methanol and inhibitory to spermatozoa at <10 microg (dry weight) ml(-1) were found from six bacterial isolates and one fungus. The substances from isolates of Bacillus simplex and from isolates belonging to the actinobacterial genera Streptomyces and Nocardiopsis were mitochondriotoxic. These substances dissipated the mitochondrial membrane potential (Deltapsi) of boar spermatozoa. The substances from the Streptomyces isolates also swelled the mitochondria. The substances from isolates of Trichoderma harzianum Rifai and Bacillus pumilus damaged the cell membrane barrier function of sperm cells.     

Fate of bioterrorism-relevant viruses and bacteria, including spores, aerosolized into an indoor air environment

An aerosol physics test facility was used in a series of eight experiments to gather an integrated comprehensive broad base of data on the fate of surrogates of microorganisms that cause smallpox, plague, glanders, anthrax, and viral hemorrhagic fevers. The results are directly relevant to the public health issue of how to protect the occupants of buildings against bioterrorism. The test conditions were directly relevant to the indoor air environment situation, and the results can be generalized to buildings that are now occupied. The reductions in concentrations of relevant viruses and bacteria--including gram-negative fermenters and nonfermenters, gram-positive cocci and bacilli, and spores--were substantial and statistically robust. The data show that the bioterrorism-relevant aerosolized viruses and bacteria, including spores, respond like small particulates to the primary (electrical) forces that control the distribution of small particulates in a room. Further, these relevant microorganisms respond like small particulates to means designed to control airborne particulates. The results could be used to anticipate the effects of a bioterrorist attack on the public health, provide information on means that can be used to minimize such effects, and used to make decisions on how best to protect occupants of specific buildings at minimal cost and with assurance of success.     

Airborne bacteria in an urban environment

Samples were taken at random intervals over a 2-year period from urban air and tested for viable bacteria. The number of bacteria in each sample was determined, and each organism isolated was identified by its morphological and biochemical characteristics. The number of bacteria found ranged from 0.013 to 1.88 organisms per liter of air sampled. Representatives of 19 different genera were found in 21 samples. The most frequently isolated organisms and their percent of occurence were Micrococcus (41%), Staphylococcus (11%), and Aerococcus (8%). The bacteria isolated were correlated with various weather and air pollution parameters using the Pearson product-moment correlation coefficient method. Statistically significant correlations were found between the number of viable bacteria isolated and the concentrations of nitric oxide (-0.45), nitrogen dioxide (+0.43), and suspended particulate pollutants (+0.56). Calculated individually, the total number of Micrococcus, Aerococcus, and Staphylococcus, number of rods, and number of cocci isolated showed negative correlations with nitric oxide and positive correlations with nitrogen dioxide and particulates. Statistically significant positive correlations were found between the total number of rods isolated and the concentration of nitrogen dioxide (+0.54) and the percent relative humidity (+0.43). The other parameters tested, sulfur dioxide, hydrocarbons, and temperature, showed no significant correlations.     

Monitoring airborne fungal spores in an experimental indoor environment to evaluate sampling methods and the effects of human activity on air sampling.

Aerobiological monitoring was conducted in an experimental room to aid in the development of standardized sampling protocols for airborne microorganisms in the indoor environment. The objectives of this research were to evaluate the relative efficiencies of selected sampling methods for the retrieval of airborne fungal spores and to determine the effect of human activity on air sampling. Dry aerosols containing known concentrations of Penicillium chrysogenum spores were generated, and air samples were taken by using Andersen six-stage, Surface Air System, Burkard, and depositional samplers. The Andersen and Burkard samplers retrieved the highest numbers of spores compared with the measurement standard, an aerodynamic particle sizer located inside the room. Data from paired samplers demonstrated that the Andersen sampler had the highest levels of sensitivity and repeatability. With a carpet as the source of P. chrysogenum spores, the effects of human activity (walking or vacuuming near the sampling site) on air sampling were also examined. Air samples were taken under undisturbed conditions and after human activity in the room. Human activity resulted in retrieval of significantly higher concentrations of airborne spores. Surface sampling of the carpet revealed moderate to heavy contamination despite relatively low airborne counts. Therefore, in certain situations, air sampling without concomitant surface sampling may not adequately reflect the level of microbial contamination in indoor environments.     

Airborne fungal spores in an industrial area: seasonal and diurnal periodicity

Qualitative and quantitative studies of atmospheric fungal spores at a chloralkali factory, Jayashree Chemicals. were made during 1993 employing culture plate and rotorod methods. A total of 57 sporulating fungal types, including three sterile mycelial forms, were recorded by the culture plate method and 51 spore types, including the hyphal fragments and unidentified spores, were recorded by the rotorod method. As to the seasonal variation, winter was found to be the greatest contributor of fungal spores as compared to the summer and rainy season. Instead, when considering the hour of the day, the peak number of fungal propagules was recorded at noon (12.00 h) followed by evening and morning values, an exception being recorded in winter months, when maximum CFUs ofCladosporium were monitored in the morning. The seasonal variation in fungal concentration and composition was found to be influenced by temperature, rainfall and relative humidity, whereas diurnal incidence was the effect of varying temperature and relative humidity during day time only. Moderate temperature and relative humidity favoured the maximum fungal spore load in the atmosphere.Cladosporium, Nigrospora, Alternaria, Lasiodiplodia, Drechslera, Pestalotia, Curvularia, Epicoccum, Aspergillus, Penicillium andChaetomium were the commonest fungal spores in the factory area.     

Airborne pollen and fungal spores in Garki,Abuja (North-Central Nigeria)

The ambient atmosphere is dominated with pollen and spores, which trigger allergic reactions and diseases and impact negatively on human health. A survey of pollen and fungal spores constituents of the atmosphere of Garki, Abuja (North-Central Nigeria) was carried out for 1 year (June 1, 2011–May 31, 2012). The aim of the study was to determine the prevalence and abundance of pollen and fungal spores in the atmosphere and their relationship with meteorological parameters. Airborne samples were trapped using modified Tauber-like pollen trap, and the recipient solutions were subjected to acetolysis. Results revealed the abundance of fungal spores, pollen, fern spores, algal cysts and diatoms in decreasing order of dominance. The atmosphere was qualitatively and quantitatively dominated by pollen during the period of late rainy/harmattan season than the rainy season. Numerous fungal spores were trapped throughout the sampling periods among which Alternaria spp., Fusarium spp., Cladosporium spp. and Curvularia spp. dominated. These fungi have been implicated in allergic diseases and are dermatophytic, causing diverse skin diseases. Other pathogenic fungi found in the studied aeroflora were Dreschlera spp., Helminthosporium spp., Torula spp., Pithomyces spp., Tetraploa spp., Nigrospora ssp., Spadicoides spp., Puccinia spp. and Erysiphe graminis. Total pollen and fungal spores counts do not show significant correlation with meteorological parameters.     

Monitoring airborne fungal spores in an experimental indoor environment to evaluate sampling methods and the effects of human activity on air sampling

[This corrects the article on p. 226 in vol. 59.].     

Airborne fungal load in agricultural environment during threshing operations

The effect of threshing operations on the fungal spora of farm air, has been studied with the culture plate method. Air samples were taken before, during and after the threshing of paddy and wheat grains, at the end of the respective crop seasons. An immediate local increase in the airborne fungal load was observed during threshing operations. In case of wheat the high rise was due toAlternaria tenuissima, followed byDrechslera sp. andCladosporium herbarum. In Boro variety of paddy, the high count was contributed byAlternaria humicola andA. tenuissima, while in Aman variety,Helminthosporium oryzae was the dominant type followed byC. herbarum and unidentified yeasts.Aspergillus spp. were observed in significant numbers before the operation started; their occurrence was negligible during threshing. A considerable number of yeast was observed, particularly during threshing and after threshing operations.     

Airborne fungal spores colonising marbles exposed in the terrace of Messina Museum, Sicily

Studies were carried out on the air and on Carraramarble blocks located in the terrace of MessinaMuseum, in order to know the likelihood of airbornefungal spores coming into contact with and colonisingtridimensional objects. Our results showed there were not significantdifferences between airborne fungi circulating inspring and in autumn; Aspergillus, Penicillium,Fusarium, Alternaria, Cladosporium,Ulocladium, Aureobasidium, Phoma were themost common isolates. However, only few species wereable to settle on the marble surfaces as demonstratedby their isolation after 2 and 6 years of exposition.     

Airborne fungal spores in the Campus of Anchieta (La Laguna,Tenerife/Canary Is.)

A quantitative and qualitative study was carried out of the atmospheric fungal propagules in two university buildings in the Campus of Anchieta (La Laguna, Tenerife, Canary Islands, Spain) and in the outdoor atmosphere, in order to ascertain the most abundant fungi and the concentration of spores in the air, as possible sources of respiratory allergies caused by this type of aeroallergens. Sampling was carried out using two kinds of traps (Burkard Personal Culture Sampler and Burkard Personal Slide Sampler), as well as adhesive tape. Sample 1, indoor, identified between 650-320 CFU m -3 depending on the culture medium, with outdoor values between 670-440 CFU m -3 ; sample 2, recorded between 630-80 CFU m -3 inside and 580-300 CFUm -3 in the outdoor atmosphere. The most represented genera were Cladosporium and Penicillium , although the following were also identified: Agaricales, Alternaria, Aspergillus, Botrytis, Drechslera, Coprinus, Curvularia, Chaetomium, Exserohilum, Fusarium, Helminthosporium, Leptosphaeria , Myxomycetes, Paecilomyces, Pleospora, Stemphylium, Tetraploa, Torula and Ulocladium .     

Airborne fungal spores in 80 homes in the Latrobe Valley, Australia: levels, seasonality and indoor-outdoor relationship

Airborne viable and total fungal spores were sampled inside and outside 80 houses in the Latrobe Valley, Victoria, Australia as part of a larger indoor environmental study. Each residence was visited six times over a period of 1 year for sample collection, and fungal spore samples were collected from at least three indoor sites and from an outdoor site. Viable spores were sampled using an Andersen sampler, while total spores were assessed using a Burkard spore trap. Identification of fungal colonies to genera level was performed in two seasons; winter and late spring. The most common fungal genera/groups wereCladosporium, Penicillium, and yeasts, both indoors and outdoors in winter and late spring. Outdoor levels were higher than those indoors throughout the year, and a significant seasonal variation in spore levels was seen both indoors and outdoors with overall maxima in summer. Contrary to this trend, the levels ofAspergillus, yeasts,Cephalosporium andGliocladium were higher in winter. Most fungal genera were found in greater concentrations outdoors compared to indoors, butPenicillium was more common indoors. Outdoor spore levels were a significant influence on indoor levels, but seasonal differences suggest that other influences are important.     

Airborne bacteria, fungi, and endotoxin levels in residential microenvironments: a case study

Limited data are currently available on the concentrations of airborne bacteria, fungi, and endotoxins in indoor environments. The levels of aerial bacteria and fungi were measured at several microenvironments within a well-ventilated residential apartment in Singapore including the living room, kitchen, bedroom, toilet, and at a workplace environment by sampling indoor air onto culture medium plates using the 6-stage Andersen sampler. Total microbial counts were determined by collecting the air samples in water with the Andersen sampler, staining the resultant extracts with a fluorescent dye, acridine orange, and counting the microbes using a fluorescent microscope. The levels of airborne endotoxins were also determined by sampling the airborne microorganisms onto 0.4?μm polycarbonate membrane filter using the MiniVol sampler at 5?l/min for 20?h with a PM_2.5 cut-off device. The aerial bacterial and fungal concentrations were found to be in the ranges of 117–2,873?CFU/m³ and 160–1,897?CFU/m³, respectively. The total microbial levels ranged from 49,000 to 218,000?microbes/m³. The predominant fungi occurring in the apartment were Aspergillus and Penicillium while the predominant bacterial strains appeared to be Staphylococcus and Micrococcus. The average indoor endotoxin level was detectable in the range of 6–39?EU/m³. The amount of ventilation and the types of human activities carried out in the indoor environment appeared to be important factors affecting the level of these airborne biological contaminants.     

广东省三种植物群落土壤AMF孢子比较

应用样方法,以三叶草(Trifolium repens)作盆栽扩繁,利用湿筛倾析法和蔗糖离心法分离土壤孢子,研究了广东省常绿阔叶林、人工林(台湾相思林、湿地松林、刚果按林)和木薯地等3种植物群落11个土样的丛枝菌根菌(Arbuscular mycorrhizal fungi,AMF)孢子组成及分布状况.根据孢子形状、颜色、大小、孢壁饰纹及连孢菌丝等形态,将所分离的孢子划分为20个形态型(morphotypes),分属于3科5属.其中球囊霉属(Glomus)有10种形态型,无梗囊霉属(Acaulospora)5种,巨孢囊霉属(Gigaspora)和盾巨孢囊霉属(Scutellospora)各2种,内养囊霉属(Entrophospora)1种.在20个形态型中,以球囊霉属最丰富,分布最广.其中4种类型Glomus dolichosporum(TypeI)、Glomus eburneum(TypeJ)、Glomus versiforme(TypeM)和Acaulospora scrobiculata(TypeD)在常绿阔叶林、人工林和木薯地中均有出现,其余类型仅见个别土样.