Bioaerosol

About: Bioaerosol is a research topic. Over the lifetime, 1347 publications have been published within this topic receiving 34791 citations.

Evaluation of ergosterol content in the air of various environments

Abstract: 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 m3 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.

Reducing bioaerosol dispersion from wastewater treatment and its land application: a review and analysis.

Abstract: Wastewater treatment systems and spray irrigation of treated water may spread microorganisms such as bacteria and viruses through dispersion of aerosol particles. A recent review (Brooks, Josephson, Gerba, & Pepper, 2004) identifies appropriate reports. Teltsch and co-authors report findings that suggest effective management controls involve providing buffer zones, irrigating in the daytime and in times of low humidity, reducing microorganism levels in water used for spraying, and testing for multiple types of viruses and bacteria (Teltsch & Katzenelson, 1978; Teltsch, Shuval, & Tadmor, 1980; Teltsch, Kedmi, Bonnet, Borenzstajn-Rotem, & Katzenelson, 1980). Camann, Moore, Harding, and Sorber support these findings. They also note that fecal streptococci are hardier than fecal coliform and appear frequently in background samples, suggesting that this bacterium is a better indicator of background and downwind conditions than are fecal coliform bacteria. In their study, storage prior to spray irrigation reduced microorganism concentrations by 99 percent. Downwind concentrations of sprayed reservoir water were often comparable to background values (Camann, Moore, Harding, & Sorber, 1988). Italian researchers (Brandi, Sisti, & Amagliani, 2000; Carducci, Gemelli, Cantiani, Casini, & Rovini, 1999; Carducci et al., 2000) confirm variable die-away rates of microorganisms, observe a positive association between fecal streptococci and the presence of viruses, and recommend consideration of submerged aeration for sludge digestion at sewage treatment plants. No reports are available that measure dispersion of bioaerosols from wastewater consistently treated to meet contemporary disinfection standards.

Total Bioaerosol Detection by a Succinimidyl-Ester-Functionalized Plasmonic Biosensor To Reveal Different Characteristics at Three Locations in Switzerland

Abstract: Bioaerosols consisting of biologically originated airborne particles such as microbes, metabolites, toxins, and fragments of microorganisms are present ubiquitously in our living environment. The international interests in bioaerosols have rapidly increased because of their many potential health effects. Thus, accurate and fast detection of total bioaerosols in different environments has become an important task for safeguarding against biological threats and broadening the pool of bioaerosol knowledge. To quickly evaluate the total bioaerosol concentration, we developed a localized surface plasmon resonance biosensor based on succinimidyl-ester-functionalized gold nanoislands (SEF-AuNIs) for quantitative bioaerosol detection. The detection limit of our proposed SEF-AuNI sensors for model bacteria Escherichia coli and Bacillus subtilis can go to 0.5119 and 1.69 cells/mL, respectively. To demonstrate the capability of this bioaerosol sensing technique, we tested aerosol samples collected from Bern (urban station), Basel (suburban station), and Rigi mountain (rural and high altitude station) in Switzerland and further investigated the correlation with endotoxin and PM10. The results substantiated that our SEF-AuNI sensors could be a reliable candidate for total bioaerosol detection and air quality assessment.

Characterization of atmospheric particles in Seoul, Korea using SEM-EDX

Abstract: Atmospheric particles in Seoul, Korea were investigated by scanning electron microscopy (SEM) equipped with energy dispersive X-ray analysis (EDX). Particles were identified and characterized by their morphology and elemental compositions. The morphology of particles was closely coupled with elemental compositions, which provided information on sources and transport processes of aerosols. There were various types of combustion-derived particles identified such as fly ashes, soot, organic matters, tar balls, chars, and sulfur-containing particles. These anthropogenic particles mainly have spherical shape with nano- to micro-meter size. Char was, however, distinguished by irregular shape with varying size up to several micrometers. The sulfur-containing aggregates show a wide range of size, shape, and elemental composition. In addition, bioaerosol and mineral dust were the most abundant particles from natural sources.

Emission of bioaerosols from livestock facilities - Methods and results from available bioaerosol investigations in and around agricultural livestock farming

Abstract: The present report reviews literature from throughout the world on methods and results of bioaerosol investigations in and around agricultural livestock farming and summarises the most important points. The global trend towards intensification and industrialisation of animal production, with regional concentration of livestock facilities and increasing numbers of animals and greater stock densities, has led to an increase in bioaerosol emissions to the environment in certain areas and to increasing concern about health impairment of the population in the vicinity. The main sources of the bioaerosols are the animals and their faeces, the litter and feed. If the particles become airborne, they can be emitted from the stables into the environment. Hundreds of different viruses, bacteria and moulds have been detected in agricultural livestock farming worldwide. The bacterial group of the Staphylococcaceae appears to be most suitable for animal husbandry as a specific indicator or guiding parameter. Bioaerosols can be measured online with particle spectrometers and offline using classical methods, i.e. sampling on site with subsequent evaluation by means of culture-based or molecular biological methods in the laboratory. The classical detection methods are best suited to the complexity of bioaerosols in agricultural livestock farming. The sampling of bioaerosols should be carried out as far as possible using standardised systems that have high physical and biological collection efficiency, in order to ensure comparability of the data. The selection of a suitable collection system should primarily depend on the issue in question. After the bioaerosols have been collected in a sample, evaluation is usually carried out via cultivation and / or various biochemical and molecular biological methods. Especially the latter, in combination with the classical culture-based methods, enable a detailed insight into the composition of bioaerosols. However, further standardisation of the methods for bioaerosols is necessary here. Endotoxins, on the other hand, are predominantly detected using the LAL test, although this test remains relatively susceptible to disturbances. Most data on bioaerosol measurements in agricultural livestock farming available for this review are from the USA and Germany. Here, the concentrations of bacteria, moulds and endotoxins were measured in the stalls of pigs, cattle and chickens. The highest concentrations of airborne bacteria were found in stalls for chickens, followed by turkeys, ducks, sheep, goats, pigs, cattle, horses and rabbits, with the different husbandry and production stages having a significant influence. Emission factors published for airborne microorganisms also differ in part considerably depending on the animal species and the type of keeping, also as a result of different sampling conditions, collection methods and different methods for determination of the concentrations. The concentrations of the airborne bacteria in livestock during the day and night can deviate by a factor of ten. The deviation may further increase by a factor of 1000 if emission factors are calculated on the basis of the specific volumetric flow rates. This must be taken into account in the calculation of annual average values of emission factors. During transportation, i.e. the transport of bioaerosols via the air, the microorganisms are largely exposed to wind and weather. The extent to which they are carried is primarily dependent on two parameters: the tenacity, i.e. the ability to survive the airborne condition, and the size and composition of the bioaerosol particles, i.e. how quickly they sediment. How long microorganisms are viable in the air is dependent on very many factors and, due to the relatively unsuitable test systems used in the past, this aspect has not been studied sufficiently. Regarding particle size, most of the airborne microorganisms found in livestock farming have a significantly larger particle size or mass fraction than would be expected from the size of the individual cells of the organisms. 30% to 70% of the bacteria can be found in mass fractions larger than PM10, whereby the distribution of the different bioaerosol components can vary considerably and is not uniformly correlated with the distribution of the dust fractions. The immission concentrations of bioaerosols exponentially decrease with the distance from the emission source, mainly depending on the particle size and meteorological conditions. Instead of carrying out complex measurements, the spread of bioaerosols can also be simulated with computer models. Up to now, however, these models have often overestimated the emissions, since night reduction, particle size distributions and death rates of the microorganisms are still not taken into account. [...]