Bioaerosol

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

Assessment of Bioaerosols and Inhalable Dust Exposure in Swiss Sawmills

Abstract: An assessment of wood workers' exposure to airborne cultivable bacteria, fungi, inhalable endotoxins and inhalable organic dust was performed at 12 sawmills that process mainly coniferous wood species. In each plant, samples were collected at four or five different work sites (debarking, sawing, sorting, planing and sawing cockpit) and the efficiency of sampling devices (impinger or filter) for determining endotoxins levels was evaluated. Results show that fungi are present in very high concentrations (up to 35 000 CFU m(-3)) in all sawmills. We also find that there are more bioaerosols at the sorting work site (mean +/- SD: 7723 +/- 9919 CFU m(-3) for total bacteria, 614 +/- 902 CFU m(-3) for Gram-negative, 19 438 +/- 14 246 CFU m(-3) for fungi, 7.0 +/- 9.0 EU m(-3) for endotoxin and 2.9 +/- 4.8 g m(-3) for dust) than at the sawing station (mean +/- SD: 1938 +/- 2478 CFU m(-3) for total bacteria, 141 +/- 206 CFU m(-3) for Gram-negative, 12 207 +/- 10 008 CFU m(-3) for fungi, 2.1 +/- 1.9 EU m(-3) for endotoxin and 0.75 +/- 0.49 mg m(-3) for dust). At the same time, the species composition and concentration of airborne Gram-negative bacteria were studied. Penicillinium sp. were the predominant fungi, while Bacillus sp. and the Pseudomonadacea family were the predominant Gram-positive and Gram-negative bacteria encountered, respectively.

Using the WIBS-4 (Waveband Integrated Bioaerosol Sensor) Technique for the On-Line Detection of Pollen Grains

Abstract: Primary biological aerosol particles (PBAP) such as pollen and fungal spores can induce allergenic responses and affect health in general. Conditions such as allergic rhinitis (hay fever) and asthma have been related to pollen concentrations. Likewise some pollen have been shown to induce ice nucleation and cloud condensation at higher temperatures than those associated with some chemical species, thereby affecting planet Earth's albedo and overall radiative balance. Hence, the near real-time (on-line) monitoring of airborne pollen and other PBAP using a variety of spectroscopic and light scattering techniques represents an area of growing development and consequence. In this study, two separate field campaigns (one at a rural site in Ireland and the other at an urbanized location in Germany) were performed to detect and quantify pollen releases using a novel on-line fluorescence spectrometer (WIBS-4). The results were compared with results obtained using more traditional Hirst-type impactors. Size, “shap...

Fluorescent bioaerosol particle, molecular tracer, and fungal spore concentrations during dry and rainy periods in a semi-arid forest

Abstract: . Bioaerosols pose risks to human health and agriculture and may influence the evolution of mixed-phase clouds and the hydrological cycle on local and regional scales. The availability and reliability of methods and data on the abundance and properties of atmospheric bioaerosols, however, are rather limited. Here we analyze and compare data from different real-time ultraviolet laser/light-induced fluorescence (UV-LIF) instruments with results from a culture-based spore sampler and offline molecular tracers for airborne fungal spores in a semi-arid forest in the southern Rocky Mountains of Colorado. Commercial UV-APS (ultraviolet aerodynamic particle sizer) and WIBS-3 (wideband integrated bioaerosol sensor, version 3) instruments with different excitation and emission wavelengths were utilized to measure fluorescent aerosol particles (FAPs) during both dry weather conditions and periods heavily influenced by rain. Seven molecular tracers of bioaerosols were quantified by analysis of total suspended particle (TSP) high-volume filter samples using a high-performance anion-exchange chromatography system with pulsed amperometric detection (HPAEC-PAD). From the same measurement campaign, Huffman et al. (2013) previously reported dramatic increases in total and fluorescent particle concentrations during and immediately after rainfall and also showed a strong relationship between the concentrations of FAPs and ice nuclei (Huffman et al., 2013; Prenni et al., 2013). Here we investigate molecular tracers and show that during rainy periods the atmospheric concentrations of arabitol (35.2 ± 10.5 ng m−3) and mannitol (44.9 ± 13.8 ng m−3) were 3–4 times higher than during dry periods. During and after rain, the correlations between FAP and tracer mass concentrations were also significantly improved. Fungal spore number concentrations on the order of 104 m−3, accounting for 2–5 % of TSP mass during dry periods and 17–23 % during rainy periods, were obtained from scaling the tracer measurements and from multiple analysis methods applied to the UV-LIF data. Endotoxin concentrations were also enhanced during rainy periods, but showed no correlation with FAP concentrations. Average mass concentrations of erythritol, levoglucosan, glucose, and (1 → 3)-β-D-glucan in TSP samples are reported separately for dry and rainy weather conditions. Overall, the results indicate that UV-LIF measurements can be used to infer fungal spore concentrations, but substantial development of instrumental and data analysis methods appears to be required for improved quantification.

The microbial signature of aerosols produced during the thermophilic phase of composting.

Abstract: Aims: The microbial diversity of bioaerosols released during operational activities at composting plants is poorly understood. Identification of bacteria and fungi present in such aerosols is the prerequisite for the definition of microbial indicators that could be used in dispersal and exposure studies. Methods and Results: A culture-independent analysis of composting bioaerosols collected at five different industrial open sites during the turning of composting piles in fermentation was performed by building 16S rDNA and 18S rDNA libraries. More than 800 sequences were analysed. Although differences in the phylotypes distribution were observed from one composting site to another, similarities in the structure of microbial diversity were remarkable. The same phyla dominated in the five bioaerosols: Ascomycota among fungi, Firmicutes and Actinobacteria among bacteria. For each phylum, some dominant phylotypes were common to at least four bioaerosols. These common phylotypes belonged to Thermomyces, Aspergillus, Penicillium, Geobacillus, Planifilum, Thermoactinomyces, Saccharopolyspora, Thermobifida and Saccharomonospora. Conclusions: The microbial signature of aerosols produced during the thermophilic phase of composting was determined. The similarities observed may be explained by the selection of thermophilic and sporulating species. Significance and Impact of the Study: Several bacteria and fungi identified in this study may represent potential indicators of composting bioaerosols in air.

Collection of three bacterial aerosols by respirator and surgical mask filters under varying conditions of flow and relative humidity

Abstract: A variety of respirator filters and surgical masks were challenged with three aerosolized bacteria: Mycobacterium abscessus (M.a.) (a rod), Staphylococcus epidermidis (S.e.) (a sphere), and Bacillus subtilis (B.s.) (a rod). Tests were conducted at two flow rates (45 and 85 l./min) and two humidity levels (30 and 70%). Aerosols were measured with a total-particle, direct-reading, spectrometer and a viable particle cascade impactor. Measurements up- and downstream of the filter or mask were used in determining aerosol penetration; respirator or surgical mask fit was not evaluated. Bioaerosol penetration measured with two aerosol sampling instruments was found to correlate. Additionally, bioaerosol test parameters were evaluated with respect to their effect on penetration. Increasing flow resulted in increased penetration of all organisms while an increase in relative humidity did not exert a consistent effect on all organisms. Of the respirators approved by the National Institute for Occupational Safety and Health (NIOSH), filter efficiency was as expected with dust/mist respirators having the lowest and HEPA filters the highest efficiency. Surgical masks were the least efficient of all filters tested; these are not certified by NIOSH. Bioaerosol penetration was compared to that of a polystyrene latex sphere (PSL) aerosol. Penetration of the test aerosols was predicted on the basis of particle aerodynamic diameter and was expected to be in this order: PSL > M.a. > S.e. = B.s. The PSL aerosol was the most penetrating, as predicted. However, results showed that B.s. was more penetrating than S.e. The aerodynamic diameter may not be the best parameter for predicting aerosol penetration of non-spherical particles in these filters.