Showing papers on "Bioaerosol published in 2019"
TL;DR: The results of an inhalation risk assessment for airborne bacteria and fungi indicated that potential adverse health risks for adults mainly occurred in spring, summer, and autumn, so WWTP operators should set up effective bioaerosol controls as soon as possible to protect the health of workers, and of residents near the plant.
65 citations
TL;DR: The overall results from this study suggest that bioaerosols generated during WWTP processes can aid in the emission and dispersal of bacteria and ARGs, resulting in a possible route of human exposure and deposition into surrounding environments.
63 citations
TL;DR: The detection of adenosine triphosphate (ATP) and recovery of bacteria possessing extreme tolerance to desiccation and shortwave ultraviolet radiation confirmed that certain microorganisms have the capacity to persist at lower altitudes of the stratosphere, providing constraints on the upper altitudinal boundary for microbial habitability in the biosphere.
Abstract: Bioaerosol transport in the atmosphere disperses microbial species between continents, affects human and plant health, and may influence hydrologic cycling. However, there have been few quantitative observations of bioaerosols at altitudes more than a few kilometers above the surface. Lack of data on bioaerosol distributions in the atmosphere has impeded efforts to assess the aerial dissemination of microbes and their vertical extent in the biosphere. In this study, a helium balloon payload system was used to sample microbial cells and dust particles in air masses as high as 38 km above sea level over three locations in the southwestern United States. The cell concentrations at altitudes between 3 and 29 km were highly similar (2–5 × 105 cells m−3) and approximately threefold lower than those observed in the convective boundary layer (CBL; 1 × 106 cells m−3), decreasing to 8 × 104 cells m−3 at 35–38 km. The detection of adenosine triphosphate (ATP) and recovery of bacteria possessing extreme tolerance to desiccation and shortwave ultraviolet radiation confirmed that certain microorganisms have the capacity to persist at lower altitudes of the stratosphere. Our data and related calculations provide constraints on the upper altitudinal boundary for microbial habitability in the biosphere.
49 citations
TL;DR: It is demonstrated that this approach can enable direct studies at the interface between aerobiology, atmospheric chemistry and aerosol physics to identify the factors that may affect the survival of airborne pathogens with the aim of developing infection control strategies for public health and biodefence applications.
Abstract: The airborne transmission of infection relies on the ability of pathogens to survive aerosol transport as they transit between hosts. Understanding the parameters that determine the survival of airborne microorganisms is critical to mitigating the impact of disease outbreaks. Conventional techniques for investigating bioaerosol longevity in vitro have systemic limitations that prevent the accurate representation of conditions that these particles would experience in the natural environment. Here, we report a new approach that enables the robust study of bioaerosol survival as a function of relevant environmental conditions. The methodology uses droplet-on-demand technology for the generation of bioaerosol droplets (1 to greater than 100 per trial) with tailored chemical and biological composition. These arrays of droplets are captured in an electrodynamic trap and levitated within a controlled environmental chamber. Droplets are then deposited on a substrate after a desired levitation period (less than 5 s to greater than 24 h). The response of bacteria to aerosolization can subsequently be determined by counting colony forming units, 24 h after deposition. In a first study, droplets formed from a suspension of Escherichia coli MRE162 cells (108 ml-1) with initial radii of 27.8 ± 0.08 µm were created and levitated for extended periods of time at 30% relative humidity. The time-dependence of the survival rate was measured over a time period extending to 1 h. We demonstrate that this approach can enable direct studies at the interface between aerobiology, atmospheric chemistry and aerosol physics to identify the factors that may affect the survival of airborne pathogens with the aim of developing infection control strategies for public health and biodefence applications.
46 citations
TL;DR: The composition, potential role, size distribution, and mass concentration and contribution of fungi to particulate matter was much higher than that of bacteria, suggesting the underestimated role of fungi in atmospheric aerosols.
45 citations
TL;DR: In this article, the authors focused on assessing the particulate, and culturable concentration of bacteria at five different spatially located sites in the Rajkot city and surroundings, in the western part of India.
Abstract: Bio-aerosol is an emerging pollutant of the technological age. Air pollution related episodes that are a region-specific phenomenon in our atmosphere, with bio-aerosols being the main area of the problem. The present research was focused on assessing the particulate, and culturable concentration of bacteria at five different spatially located sites in the Rajkot city and surroundings, in the western part of India. The highest (108.33 × 109 CFU m−3) and lowest (318 × 103 CFU m−3) bacterial concentrations were found in dump site and residential area, respectively. With reference to particulate concentration, higher (101.79 ± 8.09) concentrations were reported in the industrial area than other sampling locations. All sampling sites under the present study displayed greater variability of bacteria than that of particle concentration. The growth potential of various bacterial isolates from perspective bioaerosol was measured spectroscopically by measuring OD at 600 nm in rich medium. The isolate 1A displayed significantly higher growth compared to all other isolates after 24 h. Outcomes of the current work suggested that bacterial concentration was observed in the respirable fraction (< 2.5 μm) and so had the potential to penetrate the deeper part of the lungs. In addition, meteorological parameters (i.e., wind speed, temperature, and relative humidity) were measured to understand whether they had any effect on biotic matter. The temperature and relative humidity are the most important meteorological parameters responsible for the enhanced viability of bacteria. Land use and land cover feature were also studied to understand the spatial characteristics of bio-aerosol in the study area. This viewpoint summarizes available information on bio-aerosols and its impact on human health, devising strategies to understand characteristics of bio-aerosols and emphasizing the vital gaps in available knowledge such as to develop a relationship between biological agents and solid/liquid or a mixture of both to the assessment of dispersion behavior and toxicological nature during exposure.
41 citations
TL;DR: Air filtration and liquid impingement for bioaerosol sampling across a range of environmental conditions are evaluated and a resource is provided that enables molecular ecologists to select the most appropriate sampling strategy for their specific research question.
Abstract: Bioaerosols (or biogenic aerosols) have largely been overlooked by molecular ecologists. However, this is rapidly changing as bioaerosols play key roles in public health, environmental chemistry and the dispersal ecology of microbes. Due to the low environmental concentrations of bioaerosols, collecting sufficient biomass for molecular methods is challenging. Currently, no standardized methods for bioaerosol collection for molecular ecology research exist. Each study requires a process of optimization, which greatly slows the advance of bioaerosol science. Here, we evaluated air filtration and liquid impingement for bioaerosol sampling across a range of environmental conditions. We also investigated the effect of sampling matrices, sample concentration strategies and sampling duration on DNA yield. Air filtration using polycarbonate filters gave the highest recovery, but due to the faster sampling rates possible with impingement, we recommend this method for fine -scale temporal/spatial ecological studies. To prevent bias for the recovery of Gram-positive bacteria, we found that the matrix for impingement should be phosphate-buffered saline. The optimal method for bioaerosol concentration from the liquid matrix was centrifugation. However, we also present a method using syringe filters for rapid in-field recovery of bioaerosols from impingement samples, without compromising microbial diversity for high -throughput sequencing approaches. Finally, we provide a resource that enables molecular ecologists to select the most appropriate sampling strategy for their specific research question.
40 citations
TL;DR: A brief description of a state-of-the-art development in bioaerosol exposure studies supported by studies on several related subjects and concrete suggestions for how to design a full bio aerosol study that includes all of the key elements necessary to help understand the real impacts of bioaerOSol exposure in the short term are presented.
Abstract: Bioaerosols are recognized as one of the main transmission routes for infectious diseases and are responsible for other various types of health effects through inhalation and potential ingestion. Associating exposure with bioaerosol and health problems is challenging, and adequate exposure monitoring is a top priority for aerosol scientists. The multiple factors affecting bioaerosol content, the variability in the focus of each bioaerosol exposure study, and the variations in experimental design and the standardization of methods make bioaerosol exposure studies very difficult. Therefore, the health impacts of bioaerosol exposure are still poorly understood. This paper presents a brief description of a state-of-the-art development in bioaerosol exposure studies supported by studies on several related subjects. The main objective of this paper is to propose new considerations for bioaerosol exposure guidelines and the development of tools and study designs to better interpret bioaerosol data. The principal observations and findings are the discrepancy of the applicable methods in bioaerosol studies that makes result comparison impossible. Furthermore, the silo mentality helps in creating a bigger gap in the knowledge accumulated about bioaerosol exposure. Innovative and original ideas are presented for aerosol scientists and health scientists to consider and discuss. Although many examples cited herein are from occupational exposure, the discussion has relevance to any human environment. This work gives concrete suggestions for how to design a full bioaerosol study that includes all of the key elements necessary to help understand the real impacts of bioaerosol exposure in the short term. The creation of the proposed bioaerosol public database could give crucial information to control the public health. Implications: How can we move toward a bioaerosol exposure guidelines? The creation of the bioaerosol public database will help accumulate information for long-term association studies and help determine specific exposure biomarkers to bioaerosols. The implementation of such work will lead to a deeper understanding and more efficient utilization of bioaerosol studies to prevent public health hazards.
37 citations
TL;DR: Differences in the diversity profiles of the five dairy farms support the idea that the novel approach identifies a large number of fungal taxa, and the presence of a diverse portrait of fungi in air may represent a health risk for workers who are exposed on a daily basis.
36 citations
TL;DR: It is shown that exposure to bioaerosols can be associated with activities undertaken at open dumpsites and may contribute to the high prevalence of the chronic respiratory symptoms among the workers in such environments.
35 citations
TL;DR: In this paper, a photocatalytic system based on Perlite-supported ZnO and TiO2 was used to inactivate fungal/bacterial emissions from a biofilter treating ethyl acetate vapors in a steady state process.
TL;DR: The source tracker results indicated that water and the surrounding air were the two main bioaerosol sources and the contribution of water is greater at larger levels of aeration.
TL;DR: This work demonstrates the potential for airborne dispersion of enteric pathogens during pit latrine emptying operations by sampling bioaerosols from pit latrines in Blantyre, Malawi.
TL;DR: Air samples from different types of swine confinement buildings used to study the effects of the production phase on the taxonomical composition and functional potential of microbial communities in the SCBs bioaerosols showed that buildings housing weaning piglets (WP) exhibited higher abundances of Bacteroidetes and Proteobacteria than buildings housing finishing pigs (FP), gestating sows, farrowing sows (FS), and breeding boars (BB).
Abstract: Bioaerosols from swine confinement buildings (SCBs) pose a challenge to public health,and microorganisms within the SCBs bioaerosols originate from swine feces, of which the microbialcomposition is associated with the production phase. The present study adopted the wholemetagenome shotgun sequencing approach, to assess the effects of the production phase on thecomposition and functional potential of microbial populations in SCBs bioaerosols. Most annotatedproteins were assigned into domain bacteria, within which the predominant phylum was Firmicutes.The taxonomical profiles of bioaerosols from different types of piggeries showed that buildingshousing weaning piglets (WP) exhibited higher abundances of Bacteroidetes and Proteobacteria thanbuildings housing finishing pigs (FP), gestating sows (GS), farrowing sows (FS), and breeding boars(BB). Regarding the functional potential, the WP bioaerosol had more genes involved in the proteinturnover and fewer genes involved in the carbohydrate metabolism than bioaerosols from othertypes of SCBs. Furthermore, production phase influenced the antibiotic resistance genes (ARGs)profile of the SCBs bioaerosols. Bioaerosol microbiome of BB, shared a high similarity with GS, andWP bioaerosol microbiome was more similar to FP than other types of SCBs. Our study suggeststhat the production phase plays a key role in the SCBs bioaerosol microbiome.
TL;DR: The results of this study are very promising for the implementation of remote sensing technology in routine detection and quantification of airborne bioparticles in real-time which is important for allergy sufferers and physicians.
TL;DR: In this article, the authors assess bacterial aerosol levels in premises for animals (giraffes, monkeys, pheasants and ostriches) of the Krakow Zoo.
Abstract: Currently, there are almost no studies concerning bioaerosol and particulate matter levels in animal enclosures of zoos. Numerous air contamination sources can be found there, and zoos are both working environments and popular tourist objects. The aim of this study was to assess bacterial aerosol levels in premises for animals (giraffes, monkeys, pheasants and ostriches) of the Krakow Zoo. Bioaerosol samples were collected using six-stage Andersen impactor to assess the concentration and size distribution of airborne mesophilic bacteria, Gram-negative bacteria and staphylococci. Particulate matter levels (PM10, PM4, PM2.5 and PM1) were assessed using DustTrak Aerosol Monitor. The results showed that the concentration of airborne bacteria varied significantly between enclosures for the analyzed animal groups and various groups of bacteria reached their maximum concentrations in premises for different animals. The mean share of respirable fraction of bacteria was quite high—68%, with values ranging from 12.8% for Gram-negative bacteria to 98% for mannitol-positive staphylococci, indicating potential harmfulness to the health of exposed people. Dust concentrations remained at similar, relatively low levels (maximum of 0.105 mg/m3 for PM10 in rooms for giraffes). This study showed that neither bacterial bioaerosol levels, nor dust concentrations exceed the permissible values provided by Polish guidelines, but comparing the values with other countries’ limits suggests that the air could be considered as contaminated. The animals are a significant source of bioaerosol; therefore, attention should be paid to thorough cleaning of animals themselves and their premises and to maintaining appropriate levels of microclimatic parameters prevailing in the rooms.
TL;DR: This review explains and compares different methods of conventional, offline, online, and real-time detection methods of bioaerosols based on their working principles, sensitivity, and efficiency on a single platform to assist researchers in selecting appropriate methods for bioaerOSol measurement and investigation.
Abstract: Bioaerosols are biologically originated particles present in the atmosphere that can be formed from any process involving biological materials. They comprise of both living and non-living components including organisms, dispersal methods of organisms, and excretions. Bioaerosols such as airborne bacteria, fungal spores, pollen, and others possess diverse characteristics and effects. A large gap exists in the scientific understanding of the overall physical characteristics and measurement of bioaerosols. Consequently, this review aims to devise an appropriate approach to generate more scientific knowledge of bioaerosols. In addition to comparisons and discussions about the various factors affecting bioaerosols, sampling, handling, and the application of various devised analytical techniques, this review offers insight into the current state of bioaerosol research. The review focuses on instrumental and methodical strategies to understand bioaerosol measurement. Numerous studies have investigated conventional methods, advanced methods, and real-time methods that can be applied for bioaerosol monitoring. Each method is different in terms of working principle, characteristics, sensitivity, and efficiency. For the first time, this review explains and compares different methods of conventional, offline, online, and real-time detection methods of bioaerosols based on their working principles, sensitivity, and efficiency on a single platform. This will provide a clear concept and better options for selecting the appropriate method based on the research proposal. Furthermore, recent advances are summarized, and future outlooks are emphasized for bioaerosol identification and categorization. This study also encourages developing affordable and standardized methods to avoid the inter-laboratory and sampling variability to obtain a better understanding and comparison of bioaerosol measurements worldwide. Nevertheless, this work can assist researchers in selecting appropriate methods for bioaerosol measurement and investigation.
TL;DR: In this paper, the indoor air of glasshouses in a botanical garden was sampled with regard to bioaerosol quantitative and qualitative characteristics in comparison to those of the garden outdoor and adjacent street air.
TL;DR: Electron microscopy showed that the particles collected on filters in summer were predominantly of biological origin (bioaerosols), with which the observed radiocaesium activity concentration varied, and the fungal spore concentration in air was positively correlated with the radiocaeesium concentration at Namie in summer 2016.
Abstract: We observed the atmospheric resuspension of radiocaesium, derived from the Fukushima Dai-ichi Nuclear Power Plant accident, at Namie, a heavily contaminated area of Fukushima, since 2012. During the survey periods from 2012 to 2015, the activity concentrations of radiocaesium in air ranged from approximately 10-5 to 10-2 Bq per m3 and were higher in the warm season than in the cold season. Electron microscopy showed that the particles collected on filters in summer were predominantly of biological origin (bioaerosols), with which the observed radiocaesium activity concentration varied. We conducted an additional aerosol analysis based on fluorescent optical microscopic observation and high-throughput DNA sequencing technique to identify bioaerosols at Namie in 2015 summer. The concentrations of bioaerosols fluctuated the order of 106 particles per m3, and the phyla Basidiomycota and Ascomycota (true Fungi) accounted for approximately two-thirds of the bioaerosols. Moreover, the fungal spore concentration in air was positively correlated with the radiocaesium concentration at Namie in summer 2016. The bioaerosol emissions from Japanese mixed forests in the temperate zone predominately included fungal cells, which are known to accumulate radiocaesium, and should be considered an important scientific issue that must be addressed.
TL;DR: Nasopharynx sampling and microbiota could be used as a proxy of air sampling for exposure assessment studies or for the determination of exposure markers in highly contaminated agricultural environments.
Abstract: Background: Bioaerosols are a major concern for public health and sampling for exposure assessment purposes is challenging. The nasopharyngeal region could be a potent carrier of long-term bioaerosol exposure agents. This study aimed to evaluate the correlation between nasopharyngeal bacterial flora of swine workers and the swine barns bioaerosol biodiversity. Methods: Air samples from eight swine barns as well as nasopharyngeal swabs from pig workers (n = 25) and from a non-exposed control group (n = 29) were sequenced using 16S rRNA gene high-throughput sequencing. Wastewater treatment plants were used as the industrial, low-dust, non-agricultural environment control to validate the microbial link between the bioaerosol content (air) and the nasopharynxes of workers. Results: A multivariate analysis showed air samples and nasopharyngeal flora of pig workers cluster together, compared to the non-exposed control group. The significance was confirmed with the PERMANOVA statistical test (p-value of 0.0001). Unlike the farm environment, nasopharynx samples from wastewater workers did not cluster with air samples from wastewater treatment plants. The difference in the microbial community of nasopharynx of swine workers and a control group suggest that swine workers are carriers of germs found in bioaerosols. Conclusion: Nasopharynx sampling and microbiota could be used as a proxy of air sampling for exposure assessment studies or for the determination of exposure markers in highly contaminated agricultural environments.
TL;DR: A clear impact of operated landfill on microbiological air quality within the occupied location and nearby areas is indicated, considering health and safety of landfill workers and neighboring residents, who can be exposed to airborne microbial pollutants.
TL;DR: The release pattern ofBioaerosols was analyzed during vegetable waste composting through onsite direct sampling of bioaerosol, compost on the pile surface, and compost inside the windrows to have a systematic understanding of the aerosolization behavior of bacteria, archaea, and fungi during composting.
TL;DR: In this article, the 16S rRNA gene was sequenced and compared with bacterial bioaerosols present in rain and dry deposition passively collected at high-elevation sites in Sierra Nevada along a set of sampling periods lasting 3 years.
TL;DR: Results indicated that MW irradiation released endotoxins from cells into the atmosphere, most likely by exerting thermal effects, which achieved a total endotoxin removal efficiency of as high as 35%.
TL;DR: In this paper, a Wideband Integrated Bioaerosol sensor (WIBS-4A) was deployed at the summit of Mt. Tai in spring from 21 March to 8 April 2017 to quantify the abundance, size distributions, and diurnal variations of fluorescent bioaerosols and investigate the effect of different fluorescence thresholds of WIBS for ambient bioaero-soluble particles recognition.
Abstract: Primary biological aerosol particles are ubiquitous in the global atmosphere and can affect cloud formation, deteriorate air quality, and cause human infections. Mt. Tai (1,534 m a.s.l.) is an elevated site in the North China Plain where atmospheric aerosols reflect both regional advection and long-range transport. In this study, we deployed a Wideband Integrated Bioaerosol Sensor (WIBS-4A) and collected total suspended particles and eight-stage size-segregated aerosol samples at the summit of Mt. Tai in spring from 21 March to 8 April 2017 to quantify the abundance, size distributions, and diurnal variations of fluorescent bioaerosols and to investigate the effect of different fluorescence thresholds of WIBS for ambient bioaerosol recognition. During the whole sampling period, the number concentration of fluorescent particles (>0.8 μm) was 647 ± 533 L−1, accounting for 26.9% ± 10.0% by number of the total particles in that size range. Three-dimensional excitation-emission matrix fluorescence of water-soluble organic matter in size-segregated aerosols shows that humic-like substances (HULIS) are mainly in the fine mode ( 2.1 μm). From the diurnal variation, it is shown that bioaerosols can undergo transformation during long-range transport and contribute to HULIS. For bioaerosol recognition, we find that 6σ-threshold can lead to better classification of fluorescent aerosol particles for fungal spores. Overall, our results constrain the abundance of primary bioaerosols in the troposphere over East Asia and elucidate the processes for their evolution via mountain/valley breezes and long-range transport.
TL;DR: HEPA filters in the HVAC system successfully decreased the bioaerosol concentrations in the hospital environment, indicating the effectiveness of a well-designed ventilation system to eliminate site-specific variations.
Abstract: This study characterized and quantified the bacterial and fungal bioaerosols in nine wards of the Razavi Hospital (Mashhad, Iran) that is equipped with an advanced heating, ventilating, and air conditioning (HVAC) system including HEPA filters for air cleaning. In this study, 432 samples were taken from the indoor air of multiple hospital wards during the morning and afternoon shifts during summer and autumn. The particle number concentrations with sizes of > 0.3, > 0.5, > 1, > 2, > 5, and > 10 μm were measured using a 6-channel handheld particle counter. A greater diversity of bioaerosol types were observed during the morning shifts and during summer. The microbial load was not affected significantly by the temperature, relative humidity, working shift, season, and number of visitors, indicating the effectiveness of a well-designed ventilation system to eliminate site-specific variations. For microbial number concentrations, a significant correlation was only observed between the number of particles with a diameter of > 10 μm and the airborne microbial loading. Thus, passive sampling may not properly reflect the actual concentrations of smaller bioaerosols. In conclusion, HEPA filters in the HVAC system successfully decreased the bioaerosol concentrations in the hospital environment. Additionally, we recommend that active sampling be used in cases where a well-functioning HVAC system exists.
TL;DR: Bioaerosol sampling using PTFE samplers is an effective hands-off approach for detecting influenza virus activity among swine and mobile data collection stands to be an invaluable tool in the field by allowing secure, real-time reporting of sample collection and results.
Abstract: Influenza A virus in swine is of significant importance to human and veterinary public health. Environmental sampling techniques that prove practical would enhance surveillance for influenza viruses in swine. The primary objective of this study was to demonstrate the feasibility of bioaerosol and surface sampling for the detection of influenza virus in swine barns with a secondary objective of piloting a mobile application for data collection. Sampling was conducted at a large swine operation between July 2016 and August 2017. Swine oral fluids and surface swabs were collected from multiple rooms. Room-level air samples were collected using four bioaerosol samplers: a low volume polytetrafluoroethylene (PTFE) filter sampler, the National Institute for Occupational Safety and Health's low volume cyclone sampler, a 2-stage Andersen impactor and/or one high volume cyclonic sampler. Samples were analysed using quantitative RT-PCR. Data and results were reported using a mobile data application. Eighty-nine composite oral fluid samples, 70 surface swabs and 122 bioaerosol samples were analysed. Detection rates for influenza virus RNA in swine barn samples were 71.1% for oral fluids, 70.8% for surface swabs and 71.1% for the PTFE sampler. Analysis revealed a statistically significant relationship between the results of the PTFE sampler and the surface swabs with oral fluid results (p < 0.001 and p < 0.01 respectively). In addition, both the PTFE sampler (p < 0.01) and surface swabs (p = 0.03) significantly correlated with, and predicted oral fluid results. Bioaerosol sampling using PTFE samplers is an effective hands-off approach for detecting influenza virus activity among swine. Further study is required for the implementation of this approach for surveillance and risk assessment of circulating influenza viruses of swine origin. In addition, mobile data collection stands to be an invaluable tool in the field by allowing secure, real-time reporting of sample collection and results.
TL;DR: In this article, the ambient bioaerosols were measured in PM2.5 and PM10 samples taken in Huangshi City, Hubei Province, China, during autumn and winter from November 2017 to February 2018.
Abstract: The ambient bioaerosols were measured in PM2.5 and PM10 samples taken in Huangshi City, Hubei Province, China, during autumn and winter from November 2017 to February 2018. Both the bioaerosol number concentration and size distribution (0.37–16 µm) were obtained by direct fluorescent staining coupled with microscopic imaging. The bioaerosol number concentrations ranged from 0.05 to 3.4 # cm–3 for PM2.5 and from 0.17 to 5.7 # cm–3 for PM10, with averages of 0.90 # cm–3 and 1.9 # cm–3, respectively. In terms of particle number, the bioaerosols were dominated by fine particles (0.37–2.5 µm in diameter), with a larger proportion of submicron than supermicron particles. Assuming a unit density of 1 g cm–3 and a spherical shape for the particles, the mass abundances of the bioaerosols were estimated to be 2.4 ± 1.9% and 4.8 ± 3.2% of the PM2.5 and PM10, respectively, as measured by a nearby compliance monitor. Higher bioaerosol concentrations were observed in winter than autumn and on polluted than non-polluted days. During heavily polluted conditions, bioaerosols in the PM2.5 and PM10 were enriched by 6 and 3.7 times, respectively, compared to non-polluted days and contributed up to 15% of the PM10 mass. Rainfall and snowfall appeared to lower the bioaerosol levels. As enhanced emission controls on combustion and dust sources decrease PM levels in China, the bioaerosol fraction in measured PM concentrations will likely increase.
TL;DR: Staphylococcus was found to drive the difference in the bacterial community of tetracycline-resistant bacteria to total culturable bacteria and erythromycin-resistantacteria and also the difference from aerosol to manure samples, which would help in evaluating the risk to human and livestock health and tracing the source of airborne antibiotic- resistant bacteria in animal farms.
Abstract: Confined animal feeding operations generate high levels of airborne antibiotic-resistant bacteria, including pathogenic strains that may pollute the local environment or pose a health risk to both animals and workers. However, the communities of airborne antibiotic-resistant bacteria in such operations are not fully understood, especially in fine particles that penetrate deeply into the respiratory system. To address these gaps, manures and aerosols from inside and outside of animal houses were collected, and the characteristics of antibiotic-resistant bacteria were analyzed using Illumina MiSeq sequencing to amplify the V3-V4 region of bacterial 16S rRNA. The results indicated that animal species was the main factor that influenced the bacterial community of both manure and aerosol samples, while antibiotic selection was the major factor that influenced the bacterial community of aerosol samples from the inside of animal houses. An obvious clustering difference was detected between manure and aerosol samples. No significant difference in both alpha- and beta-diversity indices was detected between fine and coarse particles. As a key genus, Staphylococcus was found to drive the difference in the bacterial community of tetracycline-resistant bacteria to total culturable bacteria and erythromycin-resistant bacteria and also the difference in the bacterial community from aerosol to manure samples. Current data would help in evaluating the risk to human and livestock health and tracing the source of airborne antibiotic-resistant bacteria in animal farms.
TL;DR: Bacteria and fungi are part of the bioaerosol components of PM2.5 and their inhalation health risks in an industrial vicinity in South Africa were determined and children inhaled a higher dose of bacterial and fungal aerosols than adults.
Abstract: There is a growing concern that exposure to particulate matter of aerodynamic diameter of less than 2.5 µm (PM2.5) with biological composition (bioaerosols) may play a key role in the prevalence of adverse health outcomes in humans. This study determined the bacterial and fungal concentrations in PM2.5 and their inhalation health risks in an industrial vicinity in South Africa. Samples of PM2.5 collected on a 47-mm glass fiber filter during winter and summer months were analysed for bacterial and fungal content using standard methods. The health risks from inhalation of bioaerosols were done by estimating the age-specific dose rate. The concentration of bacteria (168–378 CFU/m3) was higher than fungi (58–155 CFU/m3). Bacterial and fungal concentrations in PM2.5 were lower in winter than in the summer season. Bacteria identified in summer were similar to those identified in winter: Staphylococcus sp., Bacillus sp., Micrococcus sp., Flavobacterium sp., Klebsiella sp. and Pseudomonas sp. Moreover, the fungal floras identified include Cladosporium spp., Aspergillus spp., Penicillium spp., Fusarium spp. and Alternaria spp. Children inhaled a higher dose of bacterial and fungal aerosols than adults. Bacteria and fungi are part of the bioaerosol components of PM2.5. Bioaerosol exposure may present additional health risks for children.