There are limited biosecurity measures directed at preventing airborne transmission of viruses in swine.The effectiveness of dust mitigation strategies such as oil sprinkling,to decrease risk of airborne virus transmi...There are limited biosecurity measures directed at preventing airborne transmission of viruses in swine.The effectiveness of dust mitigation strategies such as oil sprinkling,to decrease risk of airborne virus transmission are unknown.Metagenomics and qPCR for common fecal viruses were used to hunt for a ubiquitous virus to serve as a proxy when evaluating the efficiency of mitigation strategies against airborne viral infectious agents.Air particles were collected from swine buildings using high-volume air samplers.Extracted DNA and RNA were used to perform specific RT-qPCR and qPCR and analyzed by highthroughput sequencing.Porcine astroviruses group 2 were common(from 102 to 105 genomic copies per cubic meter of air or gc/m^(3),93%positivity)while no norovirus genogroup II was recovered from air samples.Porcine torque teno sus virus were detected by qPCR in low concentrations(from 101 to 102 gc/m^(3),47%positivity).Among the identified viral families by metagenomics analysis,Herelleviridae,Microviridae,Myoviridae,Podoviridae,and Siphoviridae were dominant.The phage vB_AviM_AVP of Aerococcus was present in all air samples and a newly designed qPCR revealed between 101 and 105 gc/m^(3) among the samples taken for the present study(97%positivity)and banked samples from5-and 15-year old studies(89%positivity).According to the present study,both the porcine astrovirus group 2 and the phage vB_AviM_AVP of Aerococcus could be proxy for airborne viruses of swine buildings.展开更多
Pharmaceutical wastewater treatment plants（WWTPs） are thought to be a ＂seedbed＂ and reservoirs for multi-antibiotic resistant pathogenic bacteria which can be transmitted to the air environment through aeration. W...Pharmaceutical wastewater treatment plants（WWTPs） are thought to be a ＂seedbed＂ and reservoirs for multi-antibiotic resistant pathogenic bacteria which can be transmitted to the air environment through aeration. We quantified airborne multi-antibiotic resistance in a full-scale plant to treat antibiotics-producing wastewater by collecting bioaerosol samples from December2014 to July 2015. Gram-negative opportunistic pathogenic bacteria（GNOPB） were isolated, and antibiotic susceptibility tests against 18 commonly used antibiotics, including 11 β-lactam antibiotics, 3 aminoglycosides, 2 fluoroquinolones, 1 furan and 1 sulfonamide, were conducted.More than 45% of airborne bacteria isolated from the pharmaceutical WWTP were resistant to three or more antibiotics, and some opportunistic pathogenic strains were resistant to 16 antibiotics, whereas 45.3% and 50.3% of the strains isolated from residential community and municipal WWTP showed resistance to three or more antibiotics. The calculation of the multiple antibiotic resistance（MAR） index demonstrated that the air environment in the pharmaceutical WWTP was highly impacted by antibiotic resistance, while the residential community and municipal WWTP was less impacted by antibiotic resistance. In addition, we determined that the dominant genera of opportunistic pathogenic bacteria isolated from all bioaerosol samples were Acinetobacter, Alcaligenes, Citrobacter, Enterobacter, Escherichia, Klebsiella, Pantoea, Pseudomonas and Sphingomonas. Collectively, these results indicate the proliferations and spread of antibiotic resistance through bioaerosols in WWTP treating cephalosporin-producing wastewater, which imposed a potential health risk for the staff and residents in the neighborhood, calling for administrative measures to minimize the air-transmission hazard.展开更多
Sulfur dioxide（SO_2） and benzene homologs are frequently present in the off-gas during the process of sewage sludge drying. A laboratory scale biofilter was set up to co-treat SO_2 and o-xylene in the present study....Sulfur dioxide（SO_2） and benzene homologs are frequently present in the off-gas during the process of sewage sludge drying. A laboratory scale biofilter was set up to co-treat SO_2 and o-xylene in the present study. SO_2 and o-xylene could be removed simultaneously in a single biofilter. Their concentration ratio in the inlet stream influenced the removal efficiencies. It is worth noting that the removal of SO_2 could be enhanced when low concentrations of o-xylene were introduced into the biofilter. Pseudomonas sp., Paenibacillus sp., and Bacillus sp. were the main functional bacteria groups in the biofilter. Sulfur-oxidizing bacteria（SOB） and o-xylene-degrading bacteria（XB） thrived in the biofilter and their counts as well as their growth rate increased with the increase in amount of SO2 and o-xylene supplied. The microbial populations differed in counts and species due to the properties and components of the compounds being treated in the biofilter. The presence of mixed substrates enhanced the diversity of the microbial population. During the treatment process, bioaerosols including potentially pathogenic bacteria, e.g., Acinetobacter lwoffii and Aeromonas sp., were emitted from the biofilter. Further investigation is needed to focus on the potential hazards caused by the bioaerosols emitted from waste gas treatment bioreactors.展开更多
Bioaerosols from wastewater treatment processes are a significant subgroup of atmospheric aerosols. In the present study,airborne microorganisms generated from a wastewater treatment station（WWTS） that uses an oxida...Bioaerosols from wastewater treatment processes are a significant subgroup of atmospheric aerosols. In the present study,airborne microorganisms generated from a wastewater treatment station（WWTS） that uses an oxidation ditch process were diminished by ventilation.Conventional sampling and detection methods combined with cloning/sequencing techniques were applied to determine the groups,concentrations,size distributions,and species diversity of airborne microorganisms before and after ventilation. There were 3021 ± 537 CFU/m3 of airborne bacteria and 926 ± 132 CFU/m3 of airborne fungi present in the WWTS bioaerosol.Results showed that the ventilation reduced airborne microorganisms significantly compared to the air in the WWTS. Over 60% of airborne bacteria and airborne fungi could be reduced after4 hr of air exchange. The highest removal（92.1% for airborne bacteria and 89.1% for fungi） was achieved for 0.65–1.1 μm sized particles. The bioaerosol particles over 4.7 μm were also reduced effectively. Large particles tended to be lost by gravitational settling and small particles were generally carried away,which led to the relatively easy reduction of bioaerosol particles0.65–1.1 μm and over 4.7 μm in size. An obvious variation occurred in the structure of the bacterial communities when ventilation was applied to control the airborne microorganisms in enclosed spaces.展开更多
Bioaerosols were collected by using a six-stage bioaerosols sampler from September 2007 to August 2008 in the coastal region of Qingdao, China. The terrestrial and marine microbes(including bacteria and fungi) were an...Bioaerosols were collected by using a six-stage bioaerosols sampler from September 2007 to August 2008 in the coastal region of Qingdao, China. The terrestrial and marine microbes(including bacteria and fungi) were analyzed in order to understand the distribution features of bioaerosols. The results show that the average monthly concentrations of terrestrial bacteria, marine bacteria, terrestrial fungi and marine fungi are in the ranges of 80–615 CFU m-3, 91–468 CFU m-3, 76–647 CFU m-3 and 231–1959 CFU m-3, respectively. The concentrations of terrestrial bacteria, marine bacteria, terrestrial fungi, marine fungi and total microbes are the highest in each microbial category during fall, high in spring, and the lowest in the summer and winter. The bacterial particles are coarse in spring, autumn and winter. The sizes of fungal particle present the log-normal distribution in all the seasons.展开更多
Microbial diversity and abundance in bioaerosols of a coal mine were analyzed based on 454 pyrosequencing and real-time polymerase chain reaction（PCR）. A total of 37,191 high quality sequences were obtained and coul...Microbial diversity and abundance in bioaerosols of a coal mine were analyzed based on 454 pyrosequencing and real-time polymerase chain reaction（PCR）. A total of 37,191 high quality sequences were obtained and could be classified into 531, 1730 and 448 operational taxonomic units respectively for archaea, bacteria and fungi at 97% sequence similarity. The Shannon diversity index for archaea, bacteria and fungi was respectively 4.71, 6.29 and 3.86, indicating a high diversity in coal mine bioaerosols. Crenarchaeota, Proteobacteria and Ascomycota were the dominant phyla for archaea, bacteria and fungi, respectively. The concentrations of total archaea, bacteria and fungi were 1.44 × 10^8, 1.02 × 10^8 and 9.60 × 10^4cells/m^3, respectively.Methanotrophs observed in bioaerosols suggested possible methane oxidation in the coal mine. The identified potential pathogens to coal miners, such as Acinetobacter schindleri,Aeromonas cavernicola, Alternaria alternata, Aspergillus penicillioides, Cladosporium cladosporioides,and Penicillium brevicompactum were also observed. This was the first investigation of microbial diversity and abundance in coal mine bioaerosols. The investigation of microbial communities would be favorable in promoting the progress of methane control based on microbial technique and concern on coal miners＇ health.展开更多
Objective To develop a new sampling medium for detecting of bioaerosols. Methods The sampling media were tested by using Escherichia coli, Staphylococcus aureus and Serratia marcescens under static and active conditio...Objective To develop a new sampling medium for detecting of bioaerosols. Methods The sampling media were tested by using Escherichia coli, Staphylococcus aureus and Serratia marcescens under static and active conditions, preliminary applications were performed using AGI-10 and high volume sampler. Results The average recovery rates were raised to 24.7%, 58.2%, 40.5%, 44.1%, 20.5%, and 15.4%, respectively in six consecutive experiments under static condition for 60 min at room temperature. Four kinds of sampling media were singled out after static experiments, which were referred to as “samplutions” PD1, PX2, TD1, and TX2, respectively. Under the active condition, the protective efficacy of PD1, PX2, TD1, and TX2 was 226% (153/47), 553% (111/17), 150% (120/48), and 268% (419/114), respectively. Conclusion The samplutions have some effects on the subsequent nucleic acid detection, which could be avoided by employing standard nucleic acid extraction procedure. The newly developed samplution can be applied to the detection of bioaerosols.展开更多
Bioaerosols significantly affect atmospheric processes while they undergo long-range vertical and horizontal transport and influence atmospheric chemistry and physics and climate change.Accumulating evidence suggests ...Bioaerosols significantly affect atmospheric processes while they undergo long-range vertical and horizontal transport and influence atmospheric chemistry and physics and climate change.Accumulating evidence suggests that exposure to bioaerosols may cause adverse health effects,including severe disease.Studies of bioaerosols have primarily focused on their chemical composition and largely neglected their biological composition and the negative effects of biological composition on ecosystems and human health.Here,current molecular methods for the identification,quantification,and distribution of bioaerosol agents are reviewed.Modern developments in environmental microbiology technology would be favorable in elucidation of microbial temporal and spatial distribution in the atmosphere at high resolution.In addition,these provide additional supports for growing evidence that microbial diversity or composition in the bioaerosol is an indispensable environmental aspect linking with public health.展开更多
Bioaerosol emissions from animal feeding operation (AFO) facilities are of increasing interest due to the magnitude of the emissions and their potential health effect on local communities. There is limited information...Bioaerosol emissions from animal feeding operation (AFO) facilities are of increasing interest due to the magnitude of the emissions and their potential health effect on local communities. There is limited information about fate and transport of AFO bioaerosol emissions. In this study, concentrations of airborne bacteria and fungi were measured at four ambient stations in four wind directions surrounding an egg production farm through winter, spring and summer using Andersen six-stage samplers. Mean concentrations of ambient bacteria and fungi ranged from 8.7 × 102 CFU m-3 to 1.3 × 103 CFU m-3 and from 2.8 × 102 CFU m-3 to 1.4 × 103 CFU m-3, respectively. Ambient bacterial concentrations were not significantly different over the seasons, while ambient fungal concentrations were the highest in summer and the lowest in winter. There were significant differences between downwind and upwind bacterial concentrations (p < 0.0001). Downwind bacterial and fungal concentrations responded differently to the influencing factors. Bacterial concentrations were quadratically correlated with wind vector (combined effects of wind speed and direction) and emission rate, were positively correlated with temperature, and were negatively correlated with solar radiation. Fungal concentrations were positively correlated with temperature, RH, and emission rate, and were negatively correlated with wind vector.展开更多
This study aimed to evaluate the suitability of two bioaerosol generation systems（dry and wet generation） for the aerosolization of microorganisms isolated from the International Space Station, and to calibrate the ...This study aimed to evaluate the suitability of two bioaerosol generation systems（dry and wet generation） for the aerosolization of microorganisms isolated from the International Space Station, and to calibrate the produced bioaerosols to fulfill the requirements of computational fluid dynamics model（CFD） validation. Concentration, stability, size distribution, agglomeration of generated bioaerosol and deposition of bioaerosols were analyzed. In addition, the dispersion of non-viable particles in the air was studied.Experiments proved that wet generation from microbial suspensions could be used for the production of well-calibrated and stabile bioaerosols for model validation. For the simulation of the natural release of fungal spores, a dry generation method should be used. This study showed that the used CFD model simulated the spread of non-viable particles fairly well. The mathematical deposition model by Lai and Nazaroff could be used to estimate the deposition velocities of bioaerosols on surfaces, although it somewhat underestimated the measured deposition velocities.展开更多
Microorganisms constitute an essential component in the indoor environment,which is closely related to hu-man health.However,there is limited evidence regarding the associations between indoor airborne microbiome and ...Microorganisms constitute an essential component in the indoor environment,which is closely related to hu-man health.However,there is limited evidence regarding the associations between indoor airborne microbiome and systemic inflammation,as well as whether this association is modified by indoor particulate matter and the underlying mechanisms.In this prospective repeated-measure study among 66 participants,indoor airborne mi-crobiome was characterized using amplicon sequencing and qPCR.Indoor fine particulate matter(PM_(2.5))and inhalable particulate matter(PM10)were measured.Systemic inflammatory biomarkers were assessed,including white blood cell(WBC),neutrophil(NEUT),monocyte,eosinophil counts,and their proportions.Targeted serum amino acid metabolomics were conducted to explore the underlying mechanisms.Linear mixed-effect models re-vealed that bacterial and fungal Simpson diversity were significantly associated with decreased WBC and NEUT.For example,for each interquartile range increase in the bacterial Simpson diversity,WBC and NEUT changed by-4.53%(95%CI:-8.25%,-0.66%)and-5.95%(95%CI:-11.3%,-0.27%),respectively.Notably,increased inflammatory risks of airborne microbial exposure were observed when indoor PM_(2.5) and PM10 levels were below the WHO air quality guidelines.Mediation analyses indicated that dopamine metabolism partially mediated the anti-inflammatory effects of fungal diversity exposure.Overall,our study indicated protection from a diverse indoor microbial environment on cardiovascular health and proposed an underlying mechanism through amino acid metabolism.Additionally,health risks associated with microbial exposure deserve more attention in con-texts of low indoor particulate matter pollution.Further research is necessary to fully disentangle the complex relationships between indoor microbiome,air pollutants,and human health.展开更多
Characterizations and relationships between indoor and outdoor bioaerosols were examined in an occupied office building, equipped with an air conditioning (HVAC) system, in Tempe, Arizona, USA. A two-stage microbial a...Characterizations and relationships between indoor and outdoor bioaerosols were examined in an occupied office building, equipped with an air conditioning (HVAC) system, in Tempe, Arizona, USA. A two-stage microbial air sampler was used to collect bioaerosols both inside and outside the office at fixed locations in space and at regular time intervals from August to December, 2000. Simultaneous measurements of bioaerosol, temperature, relative humidity, light intensity and wind speed were performed to explore the effects of environmental factors on bioaerosol levels. Twenty species of airborne bacteria and four genera of airborne fungi were found in our samples. The particle sizes of most outdoor and indoor bioaerosols were larger than 8.0 mm. According to the measurements of sampling days, the concentrations of outdoor bioaerosols were highest in the morning, but declined in the afternoon and reached the lowest point in the evening. The concentration peak of indoor bioaerosol (especially at the lower level) occurred in the evening, suggesting that the concentration of indoor bioaerosols follows that of outdoors, but with a time delay due to the lag associated with indoor-outdoor air exchange. With regard to the effects of four environmental factors temperature, relative humidity, light intensity, and wind speed, the relative humidity had the most pronounced influence on the outdoor bioaerosol concentrations with the number of bacteria and fungi increasing sharply on a day of high relative humidity in the desert area.展开更多
Recent pandemic outbreak of the corona-virus disease 2019(COVID-19)has raised widespread concerns about the importance of the bioaerosols.They are atmospheric aerosol particles of biological origins,mainly including b...Recent pandemic outbreak of the corona-virus disease 2019(COVID-19)has raised widespread concerns about the importance of the bioaerosols.They are atmospheric aerosol particles of biological origins,mainly including bacteria,fungi,viruses,pollen,and cell debris.Bioaerosols can exert a substantial impact on ecosystems,climate change,air quality,and public health.Here,we review several relevant topics on bioaerosols,including sampling and detection techniques,characterization,effects on health and air quality,and control methods.However,very few studies have focused on the source apportionment and transport of bioaerosols.The knowledge of the sources and transport pathways of bioaerosols is essential for a comprehensive understanding of the role microorganisms play in the atmosphere and control the spread of epidemic diseases associated with them.Therefore,this review comprehensively summarizes the up to date progress on the source characteristics,source identification,and diffusion and transport process of bioaerosols.We intercompare three types of diffusion and transport models,with a special emphasis on a widely used mathematical model.This review also highlights the main factors affecting the source emission and transport process,such as biogeographic regions,land-use types,and environmental factors.Finally,this review outlines future perspectives on bioaerosols.展开更多
Bioaerosols are defined as airbome particles(0.05-100 um in size)of biological origin.They are considered potentially harmful to human health as they can contain pathogens such as bacteria,fungi,and viruses.This revie...Bioaerosols are defined as airbome particles(0.05-100 um in size)of biological origin.They are considered potentially harmful to human health as they can contain pathogens such as bacteria,fungi,and viruses.This review summarizes the most recent research on the health risks of bioaerosols emitted from wastewater treatment plants(WWTPs)in order to improve the control of such bioaerosols.The concentration and size distribution of WWTP bioaerosols;their major emission sources,composition,and health risks;and considerations for future research are discussed.The major themes and findings in the literature are as follows:the major emission sources of WWTP bioaerosols include screen rooms,sludge-dewatering rooms,and acration tanks;the bioaerosol concentrations in screen and sludge-dewatering rooms are higher than those outdoors.WWTP bioacrosols contain a variety of potentially pathogenic bacteria,fungi,antibiotic resistance genes,viruses,endotoxins,and toxic metal(loid)s.These potentially,pathogenic substances spread with the bioaerosols,thereby posing health risks to workers and residents in and around the WWTP.Inhalation has been identified as the main exposure route,and children are at a higher risk of this than adults.Future studies should identify emerging contaminants,establish health risk assessments,and develop prevention and control systems.展开更多
Bioaerosols are a subset of important airborne particulates that present a substantial human health hazard due to their allergenicity and infectivity.Chemical reactions in atmospheric processes can significantly influ...Bioaerosols are a subset of important airborne particulates that present a substantial human health hazard due to their allergenicity and infectivity.Chemical reactions in atmospheric processes can significantly influence the health hazard presented by bioaerosols;however,few studies have summarized such alterations to bioaerosols and the mechanisms involved.In this paper,we systematically review the chemical modifications of bioaerosols and the impact on their health effects,mainly focusing on the exacerbation of allergic diseases such as asthma,rhinitis,and bronchitis.Oxidation,nitration,and oligomerization induced by hydroxyl radicals,ozone,and nitrogen dioxide are the major chemical modifications affecting bioaerosols,all of which can aggravate allergenicity mainly through immunoglobulin E pathways.Such processes can even interact with climate change including the greenhouse effect,suggesting the importance of bioaerosols in the future implementation of carbon neutralization strategies.In summary,the chemical modification of bioaerosols and the subsequent impact on health hazards indicate that the combined management of both chemical and biological components is required to mitigate the health hazards of particulate air pollution.展开更多
Indoor airborne bioaerosols of outdoor origin play an important role in determining the exposure of humans to bioaerosols because people spend most of their time indoors. However, there are few studies focusing on ind...Indoor airborne bioaerosols of outdoor origin play an important role in determining the exposure of humans to bioaerosols because people spend most of their time indoors. However, there are few studies focusing on indoor bioaerosols originating from outdoors. In this study, indoor versus outdoor size-resolved concentrations and particle asymmetry factors of airborne fluorescent bioaerosols in an office room were measured continuously for 6 days （144 h） using a fluorescent bioaerosol detector. The windows and door of this room were closed to ensure that there was only air infiltration; moreover, any human activities were ceased during sampling to inhibit effects of indoor sources. We focused on fine particles, since few coarse particles enter indoor environments, when windows and doors are closed. Both indoor and outdoor fluorescent bioaerosol size distributions were fit with two-mode lognormal distributions （indoor R2 = 0.935, outdoor R2 = 0.938）. Asymmetry factor distributions were also fit with lognormal distributions （indoor R2 = 0.992, outdoor R2 = 0.992）. Correlations between indoor and outdoor fluorescent bioaerosol concentrations show significant concentration-attenuation and a time lag during the study period. A two-parameter, semi-empirical model was used to predict concentrations of indoor fluorescent bioaerosols of outdoor origin. The measured and predicted concentrations had a linear relationship for the studied size fractions, with an R2 for all size fractions of larger than 0.83.展开更多
The aerosol transmission of coronavirus disease in 2019,along with the spread of other respiratory diseases,caused significant loss of life and property;it impressed upon us the importance of real-time bioaerosol dete...The aerosol transmission of coronavirus disease in 2019,along with the spread of other respiratory diseases,caused significant loss of life and property;it impressed upon us the importance of real-time bioaerosol detection.The complexity,diversity,and large spatiotemporal variability of bioaerosols and their external/internal mixing with abiotic components pose challenges for effective online bioaerosol monitoring.Traditional methods focus on directly capturing bioaerosols before subsequent time-consuming laboratory analysis such as culture-based methods,preventing the high-resolution time-based characteristics necessary for an online approach.Through a comprehensive literature assessment,this review highlights and discusses the most commonly used real-time bioaerosol monitoring techniques and the associated commercially available monitors.Methods applied in online bioaerosol monitoring,including adenosine triphosphate bioluminescence,laser/light-induced fluorescence spectroscopy,Raman spectroscopy,and bioaerosol mass spectrometry are summarized.The working principles,characteristics,sensitivities,and efficiencies of these real-time detection methods are compared to understand their responses to known particle types and to contrast their differences.Approaches developed to analyze the substantial data sets obtained by these instruments and to overcome the limitations of current real-time bioaerosol monitoring technologies are also introduced.Finally,an outlook is proposed for future instrumentation indicating a need for highly revolutionized bioaerosol detection technologies.展开更多
Bioaerosol, an important constituent of the atmosphere, can directly affect light radiation characteristics due to absorption and scattering effects. Current research lacks a reasonable explanation for the extinction ...Bioaerosol, an important constituent of the atmosphere, can directly affect light radiation characteristics due to absorption and scattering effects. Current research lacks a reasonable explanation for the extinction abilities of bioaerosols in a broadband. Herein, we measured the reflectance spectra of 12 com m on biomaterials and calculated their complex refractive indexes. The peaks of the imaginary part of the complex refractive indexes are located at wavelengths of approximately 0.7, 2.7, 6.1 and 9.5μm. Based on photographs of the floating structures of bioaerosols, we constructed a model for calculating the extinction abilities of bioaerosols in the wavelength range of 240 nm to 14 (im. Taking AN02 spores as an example, absorption was found to account for more than 90% of the total extinction. In addition, the theoretical calculations and experimental data of transmittance corresponding to the smoke box show that bioaerosol exhibits significant broadband extinction ability from UV to IR bands, which provides new directions for the development of broadband light attenuation materials.展开更多
Bioaerosols exhibit significant broadband extinction performance and have vital impacts on climate change,optical detection,communication,disease transmission,and the development of optical attenuation materials.Micro...Bioaerosols exhibit significant broadband extinction performance and have vital impacts on climate change,optical detection,communication,disease transmission,and the development of optical attenuation materials.Microbial spores and microbial hyphae represent two primary forms of bioaerosol particles.However,a comprehensive investigation and comparison of their optical properties have not been conducted yet.In this paper,the spectra of spores and hyphae were tested,and the absorption peaks,component contents,and protein structural differences were compared.Accurate structural models were established,and the optical attenuation parameters were calculated.Aerosol chamber experiments were conducted to verify the optical attenuation performance of microbial spores and hyphae in the mid-infrared and far-infrared spectral bands.Results demonstrate that selecting spores and hyphae can significantly reduce the average transmittance from 21.2%to 6.4%in the mid-infrared band and from 31.3%to 19.6%in the far-infrared band within three minutes.The conclusions have significant implications for the selection of high-performance microbial optical attenuation materials as well as for the rapid detection of bioaerosol types in research on climate change and the spread of pathogenic aerosols.展开更多
ObjectiveThis study was to establish a simple method for collecting and detecting Mycoplasma hyopneumoniae （Mhp） in aerosol. MethodBased on the mechanisms of liquid impinger and filtration sampler, a double concentr...ObjectiveThis study was to establish a simple method for collecting and detecting Mycoplasma hyopneumoniae （Mhp） in aerosol. MethodBased on the mechanisms of liquid impinger and filtration sampler, a double concentration aerosol sampler was designed for collecting Mhp aerosol. Firstly, the collection was performed in a closed environment full of artificial aerosol of Mhp. Secondly, collection efficiency was detected by real-time PCR. Thereafter, the clinical feasibility of the designed equipment was tested by collecting aerosol samples in different pig herds. In one assay, the samples were collected at different times from one pig house challenged with Mhp. In another assay, the samples was collected from the delivery room, nursery and fattenning house of a MPS outbreak farm as well as a Mhp infection positive pig farm without obvious clinical symptoms. All the aerosol samples were then detected by real-time PCR or nested PCR. ResultThe collection efficiency of the designed bioaerosol sampler was （37.04±6.43） %, Mhp could be detected 7 d after intratracheal challenge with pneumonic lung homogenate suspension. Aerosol samples of 11 pig houses from the two Mhp positive pig farms with or without clinical symptoms all showed a positive result of PCR, the positivity rate was 100%. ConclusionA high sensitive collecting and detecting technology of aerosol was successfully established, which can be applied to clinical detection of Mhp in aerosol.展开更多
文摘There are limited biosecurity measures directed at preventing airborne transmission of viruses in swine.The effectiveness of dust mitigation strategies such as oil sprinkling,to decrease risk of airborne virus transmission are unknown.Metagenomics and qPCR for common fecal viruses were used to hunt for a ubiquitous virus to serve as a proxy when evaluating the efficiency of mitigation strategies against airborne viral infectious agents.Air particles were collected from swine buildings using high-volume air samplers.Extracted DNA and RNA were used to perform specific RT-qPCR and qPCR and analyzed by highthroughput sequencing.Porcine astroviruses group 2 were common(from 102 to 105 genomic copies per cubic meter of air or gc/m^(3),93%positivity)while no norovirus genogroup II was recovered from air samples.Porcine torque teno sus virus were detected by qPCR in low concentrations(from 101 to 102 gc/m^(3),47%positivity).Among the identified viral families by metagenomics analysis,Herelleviridae,Microviridae,Myoviridae,Podoviridae,and Siphoviridae were dominant.The phage vB_AviM_AVP of Aerococcus was present in all air samples and a newly designed qPCR revealed between 101 and 105 gc/m^(3) among the samples taken for the present study(97%positivity)and banked samples from5-and 15-year old studies(89%positivity).According to the present study,both the porcine astrovirus group 2 and the phage vB_AviM_AVP of Aerococcus could be proxy for airborne viruses of swine buildings.
基金supported by the National Natural Science Foundation of China(No.51478237)
文摘Pharmaceutical wastewater treatment plants（WWTPs） are thought to be a ＂seedbed＂ and reservoirs for multi-antibiotic resistant pathogenic bacteria which can be transmitted to the air environment through aeration. We quantified airborne multi-antibiotic resistance in a full-scale plant to treat antibiotics-producing wastewater by collecting bioaerosol samples from December2014 to July 2015. Gram-negative opportunistic pathogenic bacteria（GNOPB） were isolated, and antibiotic susceptibility tests against 18 commonly used antibiotics, including 11 β-lactam antibiotics, 3 aminoglycosides, 2 fluoroquinolones, 1 furan and 1 sulfonamide, were conducted.More than 45% of airborne bacteria isolated from the pharmaceutical WWTP were resistant to three or more antibiotics, and some opportunistic pathogenic strains were resistant to 16 antibiotics, whereas 45.3% and 50.3% of the strains isolated from residential community and municipal WWTP showed resistance to three or more antibiotics. The calculation of the multiple antibiotic resistance（MAR） index demonstrated that the air environment in the pharmaceutical WWTP was highly impacted by antibiotic resistance, while the residential community and municipal WWTP was less impacted by antibiotic resistance. In addition, we determined that the dominant genera of opportunistic pathogenic bacteria isolated from all bioaerosol samples were Acinetobacter, Alcaligenes, Citrobacter, Enterobacter, Escherichia, Klebsiella, Pantoea, Pseudomonas and Sphingomonas. Collectively, these results indicate the proliferations and spread of antibiotic resistance through bioaerosols in WWTP treating cephalosporin-producing wastewater, which imposed a potential health risk for the staff and residents in the neighborhood, calling for administrative measures to minimize the air-transmission hazard.
基金financially supported by the National Natural Science Foundation of China(Nos.51478456 and 51308527)
文摘Sulfur dioxide（SO_2） and benzene homologs are frequently present in the off-gas during the process of sewage sludge drying. A laboratory scale biofilter was set up to co-treat SO_2 and o-xylene in the present study. SO_2 and o-xylene could be removed simultaneously in a single biofilter. Their concentration ratio in the inlet stream influenced the removal efficiencies. It is worth noting that the removal of SO_2 could be enhanced when low concentrations of o-xylene were introduced into the biofilter. Pseudomonas sp., Paenibacillus sp., and Bacillus sp. were the main functional bacteria groups in the biofilter. Sulfur-oxidizing bacteria（SOB） and o-xylene-degrading bacteria（XB） thrived in the biofilter and their counts as well as their growth rate increased with the increase in amount of SO2 and o-xylene supplied. The microbial populations differed in counts and species due to the properties and components of the compounds being treated in the biofilter. The presence of mixed substrates enhanced the diversity of the microbial population. During the treatment process, bioaerosols including potentially pathogenic bacteria, e.g., Acinetobacter lwoffii and Aeromonas sp., were emitted from the biofilter. Further investigation is needed to focus on the potential hazards caused by the bioaerosols emitted from waste gas treatment bioreactors.
基金financially supported by the National Key Technology R & D Program of China (No.2012BAC13B04-08)the National Natural Science Foundation of China (Nos.51178451 and 51221892)
文摘Bioaerosols from wastewater treatment processes are a significant subgroup of atmospheric aerosols. In the present study,airborne microorganisms generated from a wastewater treatment station（WWTS） that uses an oxidation ditch process were diminished by ventilation.Conventional sampling and detection methods combined with cloning/sequencing techniques were applied to determine the groups,concentrations,size distributions,and species diversity of airborne microorganisms before and after ventilation. There were 3021 ± 537 CFU/m3 of airborne bacteria and 926 ± 132 CFU/m3 of airborne fungi present in the WWTS bioaerosol.Results showed that the ventilation reduced airborne microorganisms significantly compared to the air in the WWTS. Over 60% of airborne bacteria and airborne fungi could be reduced after4 hr of air exchange. The highest removal（92.1% for airborne bacteria and 89.1% for fungi） was achieved for 0.65–1.1 μm sized particles. The bioaerosol particles over 4.7 μm were also reduced effectively. Large particles tended to be lost by gravitational settling and small particles were generally carried away,which led to the relatively easy reduction of bioaerosol particles0.65–1.1 μm and over 4.7 μm in size. An obvious variation occurred in the structure of the bacterial communities when ventilation was applied to control the airborne microorganisms in enclosed spaces.
基金supported by NSFC under Grant No.40705047Natural Science Foundation of Shandong Province(No.ZR2012DM003)
文摘Bioaerosols were collected by using a six-stage bioaerosols sampler from September 2007 to August 2008 in the coastal region of Qingdao, China. The terrestrial and marine microbes(including bacteria and fungi) were analyzed in order to understand the distribution features of bioaerosols. The results show that the average monthly concentrations of terrestrial bacteria, marine bacteria, terrestrial fungi and marine fungi are in the ranges of 80–615 CFU m-3, 91–468 CFU m-3, 76–647 CFU m-3 and 231–1959 CFU m-3, respectively. The concentrations of terrestrial bacteria, marine bacteria, terrestrial fungi, marine fungi and total microbes are the highest in each microbial category during fall, high in spring, and the lowest in the summer and winter. The bacterial particles are coarse in spring, autumn and winter. The sizes of fungal particle present the log-normal distribution in all the seasons.
基金supported by the National Natural Science Foundation of China (No. 21177153)the National Science and Technology Major Project, China (No. 2012ZX05060-005)the Key Research Program of the Chinese Academy of Sciences (No. KZZD-EW-09-1)
文摘Microbial diversity and abundance in bioaerosols of a coal mine were analyzed based on 454 pyrosequencing and real-time polymerase chain reaction（PCR）. A total of 37,191 high quality sequences were obtained and could be classified into 531, 1730 and 448 operational taxonomic units respectively for archaea, bacteria and fungi at 97% sequence similarity. The Shannon diversity index for archaea, bacteria and fungi was respectively 4.71, 6.29 and 3.86, indicating a high diversity in coal mine bioaerosols. Crenarchaeota, Proteobacteria and Ascomycota were the dominant phyla for archaea, bacteria and fungi, respectively. The concentrations of total archaea, bacteria and fungi were 1.44 × 10^8, 1.02 × 10^8 and 9.60 × 10^4cells/m^3, respectively.Methanotrophs observed in bioaerosols suggested possible methane oxidation in the coal mine. The identified potential pathogens to coal miners, such as Acinetobacter schindleri,Aeromonas cavernicola, Alternaria alternata, Aspergillus penicillioides, Cladosporium cladosporioides,and Penicillium brevicompactum were also observed. This was the first investigation of microbial diversity and abundance in coal mine bioaerosols. The investigation of microbial communities would be favorable in promoting the progress of methane control based on microbial technique and concern on coal miners＇ health.
文摘Objective To develop a new sampling medium for detecting of bioaerosols. Methods The sampling media were tested by using Escherichia coli, Staphylococcus aureus and Serratia marcescens under static and active conditions, preliminary applications were performed using AGI-10 and high volume sampler. Results The average recovery rates were raised to 24.7%, 58.2%, 40.5%, 44.1%, 20.5%, and 15.4%, respectively in six consecutive experiments under static condition for 60 min at room temperature. Four kinds of sampling media were singled out after static experiments, which were referred to as “samplutions” PD1, PX2, TD1, and TX2, respectively. Under the active condition, the protective efficacy of PD1, PX2, TD1, and TX2 was 226% (153/47), 553% (111/17), 150% (120/48), and 268% (419/114), respectively. Conclusion The samplutions have some effects on the subsequent nucleic acid detection, which could be avoided by employing standard nucleic acid extraction procedure. The newly developed samplution can be applied to the detection of bioaerosols.
基金supported by the National Research Foundation(NRF)of Korea via a grant(No.2011-0030040)funded by the Korea government(MSIP)GAIA project from Korea Ministry of Environment for the performance of this study
文摘Bioaerosols significantly affect atmospheric processes while they undergo long-range vertical and horizontal transport and influence atmospheric chemistry and physics and climate change.Accumulating evidence suggests that exposure to bioaerosols may cause adverse health effects,including severe disease.Studies of bioaerosols have primarily focused on their chemical composition and largely neglected their biological composition and the negative effects of biological composition on ecosystems and human health.Here,current molecular methods for the identification,quantification,and distribution of bioaerosol agents are reviewed.Modern developments in environmental microbiology technology would be favorable in elucidation of microbial temporal and spatial distribution in the atmosphere at high resolution.In addition,these provide additional supports for growing evidence that microbial diversity or composition in the bioaerosol is an indispensable environmental aspect linking with public health.
文摘Bioaerosol emissions from animal feeding operation (AFO) facilities are of increasing interest due to the magnitude of the emissions and their potential health effect on local communities. There is limited information about fate and transport of AFO bioaerosol emissions. In this study, concentrations of airborne bacteria and fungi were measured at four ambient stations in four wind directions surrounding an egg production farm through winter, spring and summer using Andersen six-stage samplers. Mean concentrations of ambient bacteria and fungi ranged from 8.7 × 102 CFU m-3 to 1.3 × 103 CFU m-3 and from 2.8 × 102 CFU m-3 to 1.4 × 103 CFU m-3, respectively. Ambient bacterial concentrations were not significantly different over the seasons, while ambient fungal concentrations were the highest in summer and the lowest in winter. There were significant differences between downwind and upwind bacterial concentrations (p < 0.0001). Downwind bacterial and fungal concentrations responded differently to the influencing factors. Bacterial concentrations were quadratically correlated with wind vector (combined effects of wind speed and direction) and emission rate, were positively correlated with temperature, and were negatively correlated with solar radiation. Fungal concentrations were positively correlated with temperature, RH, and emission rate, and were negatively correlated with wind vector.
基金funding from the European Union Seventh Framework Programme(FP/2007-2013)grant agreement number 263076 within the BIOSMHARS Project(BIO contamination Specific Modeling in Habitats Related to Space)
文摘This study aimed to evaluate the suitability of two bioaerosol generation systems（dry and wet generation） for the aerosolization of microorganisms isolated from the International Space Station, and to calibrate the produced bioaerosols to fulfill the requirements of computational fluid dynamics model（CFD） validation. Concentration, stability, size distribution, agglomeration of generated bioaerosol and deposition of bioaerosols were analyzed. In addition, the dispersion of non-viable particles in the air was studied.Experiments proved that wet generation from microbial suspensions could be used for the production of well-calibrated and stabile bioaerosols for model validation. For the simulation of the natural release of fungal spores, a dry generation method should be used. This study showed that the used CFD model simulated the spread of non-viable particles fairly well. The mathematical deposition model by Lai and Nazaroff could be used to estimate the deposition velocities of bioaerosols on surfaces, although it somewhat underestimated the measured deposition velocities.
基金supported by the National Key Research and Development Program of China(No.2022YFC3702704)the National Natural Science Foundation of China(Nos.22376005,22076006 and 82073506).
文摘Microorganisms constitute an essential component in the indoor environment,which is closely related to hu-man health.However,there is limited evidence regarding the associations between indoor airborne microbiome and systemic inflammation,as well as whether this association is modified by indoor particulate matter and the underlying mechanisms.In this prospective repeated-measure study among 66 participants,indoor airborne mi-crobiome was characterized using amplicon sequencing and qPCR.Indoor fine particulate matter(PM_(2.5))and inhalable particulate matter(PM10)were measured.Systemic inflammatory biomarkers were assessed,including white blood cell(WBC),neutrophil(NEUT),monocyte,eosinophil counts,and their proportions.Targeted serum amino acid metabolomics were conducted to explore the underlying mechanisms.Linear mixed-effect models re-vealed that bacterial and fungal Simpson diversity were significantly associated with decreased WBC and NEUT.For example,for each interquartile range increase in the bacterial Simpson diversity,WBC and NEUT changed by-4.53%(95%CI:-8.25%,-0.66%)and-5.95%(95%CI:-11.3%,-0.27%),respectively.Notably,increased inflammatory risks of airborne microbial exposure were observed when indoor PM_(2.5) and PM10 levels were below the WHO air quality guidelines.Mediation analyses indicated that dopamine metabolism partially mediated the anti-inflammatory effects of fungal diversity exposure.Overall,our study indicated protection from a diverse indoor microbial environment on cardiovascular health and proposed an underlying mechanism through amino acid metabolism.Additionally,health risks associated with microbial exposure deserve more attention in con-texts of low indoor particulate matter pollution.Further research is necessary to fully disentangle the complex relationships between indoor microbiome,air pollutants,and human health.
文摘Characterizations and relationships between indoor and outdoor bioaerosols were examined in an occupied office building, equipped with an air conditioning (HVAC) system, in Tempe, Arizona, USA. A two-stage microbial air sampler was used to collect bioaerosols both inside and outside the office at fixed locations in space and at regular time intervals from August to December, 2000. Simultaneous measurements of bioaerosol, temperature, relative humidity, light intensity and wind speed were performed to explore the effects of environmental factors on bioaerosol levels. Twenty species of airborne bacteria and four genera of airborne fungi were found in our samples. The particle sizes of most outdoor and indoor bioaerosols were larger than 8.0 mm. According to the measurements of sampling days, the concentrations of outdoor bioaerosols were highest in the morning, but declined in the afternoon and reached the lowest point in the evening. The concentration peak of indoor bioaerosol (especially at the lower level) occurred in the evening, suggesting that the concentration of indoor bioaerosols follows that of outdoors, but with a time delay due to the lag associated with indoor-outdoor air exchange. With regard to the effects of four environmental factors temperature, relative humidity, light intensity, and wind speed, the relative humidity had the most pronounced influence on the outdoor bioaerosol concentrations with the number of bacteria and fungi increasing sharply on a day of high relative humidity in the desert area.
基金the National Natural Science Foundation of China(Grant No.51478045)the Fund Project of Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control(GKECHRC-07)+1 种基金the Fund Project of Shaanxi Key Laboratory of Land Consolidation(2018-ZD04)the Opening Fund of State Key Laboratory of Green Building in Western China(LSKF202008).
文摘Recent pandemic outbreak of the corona-virus disease 2019(COVID-19)has raised widespread concerns about the importance of the bioaerosols.They are atmospheric aerosol particles of biological origins,mainly including bacteria,fungi,viruses,pollen,and cell debris.Bioaerosols can exert a substantial impact on ecosystems,climate change,air quality,and public health.Here,we review several relevant topics on bioaerosols,including sampling and detection techniques,characterization,effects on health and air quality,and control methods.However,very few studies have focused on the source apportionment and transport of bioaerosols.The knowledge of the sources and transport pathways of bioaerosols is essential for a comprehensive understanding of the role microorganisms play in the atmosphere and control the spread of epidemic diseases associated with them.Therefore,this review comprehensively summarizes the up to date progress on the source characteristics,source identification,and diffusion and transport process of bioaerosols.We intercompare three types of diffusion and transport models,with a special emphasis on a widely used mathematical model.This review also highlights the main factors affecting the source emission and transport process,such as biogeographic regions,land-use types,and environmental factors.Finally,this review outlines future perspectives on bioaerosols.
基金the Special Fund from the State Key Joint Laboratory of Environment Simulation and Pollution Control(Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences)(No.19Z03ESPCR)the National Natural Science Foundation of China(Grant Nos.51478456 and 41961134033).
文摘Bioaerosols are defined as airbome particles(0.05-100 um in size)of biological origin.They are considered potentially harmful to human health as they can contain pathogens such as bacteria,fungi,and viruses.This review summarizes the most recent research on the health risks of bioaerosols emitted from wastewater treatment plants(WWTPs)in order to improve the control of such bioaerosols.The concentration and size distribution of WWTP bioaerosols;their major emission sources,composition,and health risks;and considerations for future research are discussed.The major themes and findings in the literature are as follows:the major emission sources of WWTP bioaerosols include screen rooms,sludge-dewatering rooms,and acration tanks;the bioaerosol concentrations in screen and sludge-dewatering rooms are higher than those outdoors.WWTP bioacrosols contain a variety of potentially pathogenic bacteria,fungi,antibiotic resistance genes,viruses,endotoxins,and toxic metal(loid)s.These potentially,pathogenic substances spread with the bioaerosols,thereby posing health risks to workers and residents in and around the WWTP.Inhalation has been identified as the main exposure route,and children are at a higher risk of this than adults.Future studies should identify emerging contaminants,establish health risk assessments,and develop prevention and control systems.
基金supported by the National Natural Science Foundation of China(42293324,41961134034,and 21876002).
文摘Bioaerosols are a subset of important airborne particulates that present a substantial human health hazard due to their allergenicity and infectivity.Chemical reactions in atmospheric processes can significantly influence the health hazard presented by bioaerosols;however,few studies have summarized such alterations to bioaerosols and the mechanisms involved.In this paper,we systematically review the chemical modifications of bioaerosols and the impact on their health effects,mainly focusing on the exacerbation of allergic diseases such as asthma,rhinitis,and bronchitis.Oxidation,nitration,and oligomerization induced by hydroxyl radicals,ozone,and nitrogen dioxide are the major chemical modifications affecting bioaerosols,all of which can aggravate allergenicity mainly through immunoglobulin E pathways.Such processes can even interact with climate change including the greenhouse effect,suggesting the importance of bioaerosols in the future implementation of carbon neutralization strategies.In summary,the chemical modification of bioaerosols and the subsequent impact on health hazards indicate that the combined management of both chemical and biological components is required to mitigate the health hazards of particulate air pollution.
基金This work was supported by the National Key Research and Development Plan from the Ministry of Science and Technology of China through Grant No. 2016YFC0700500, as well as funding from Innovative Research Groups of the National Natural Science Foundation of China （No. 51521005）, and the National Natural Science Foundation of China （No. 51678328 ＆ 21221004 ＆ 41227805 ＆ 21190054）.
文摘Indoor airborne bioaerosols of outdoor origin play an important role in determining the exposure of humans to bioaerosols because people spend most of their time indoors. However, there are few studies focusing on indoor bioaerosols originating from outdoors. In this study, indoor versus outdoor size-resolved concentrations and particle asymmetry factors of airborne fluorescent bioaerosols in an office room were measured continuously for 6 days （144 h） using a fluorescent bioaerosol detector. The windows and door of this room were closed to ensure that there was only air infiltration; moreover, any human activities were ceased during sampling to inhibit effects of indoor sources. We focused on fine particles, since few coarse particles enter indoor environments, when windows and doors are closed. Both indoor and outdoor fluorescent bioaerosol size distributions were fit with two-mode lognormal distributions （indoor R2 = 0.935, outdoor R2 = 0.938）. Asymmetry factor distributions were also fit with lognormal distributions （indoor R2 = 0.992, outdoor R2 = 0.992）. Correlations between indoor and outdoor fluorescent bioaerosol concentrations show significant concentration-attenuation and a time lag during the study period. A two-parameter, semi-empirical model was used to predict concentrations of indoor fluorescent bioaerosols of outdoor origin. The measured and predicted concentrations had a linear relationship for the studied size fractions, with an R2 for all size fractions of larger than 0.83.
基金financially supported by National Natural Science Foundation of China(U1901210,42177410 and 42130611)Science and Technology Project of Guangdong Province,China(2021A0505030070)+2 种基金Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(2017BT01Z032)Science and Technology Program of Guangzhou(202201010684)and Young S&T Talent Training Program of Guangdong Provincial Association for S&T(GDSTA),China(2022QNRC23).
文摘The aerosol transmission of coronavirus disease in 2019,along with the spread of other respiratory diseases,caused significant loss of life and property;it impressed upon us the importance of real-time bioaerosol detection.The complexity,diversity,and large spatiotemporal variability of bioaerosols and their external/internal mixing with abiotic components pose challenges for effective online bioaerosol monitoring.Traditional methods focus on directly capturing bioaerosols before subsequent time-consuming laboratory analysis such as culture-based methods,preventing the high-resolution time-based characteristics necessary for an online approach.Through a comprehensive literature assessment,this review highlights and discusses the most commonly used real-time bioaerosol monitoring techniques and the associated commercially available monitors.Methods applied in online bioaerosol monitoring,including adenosine triphosphate bioluminescence,laser/light-induced fluorescence spectroscopy,Raman spectroscopy,and bioaerosol mass spectrometry are summarized.The working principles,characteristics,sensitivities,and efficiencies of these real-time detection methods are compared to understand their responses to known particle types and to contrast their differences.Approaches developed to analyze the substantial data sets obtained by these instruments and to overcome the limitations of current real-time bioaerosol monitoring technologies are also introduced.Finally,an outlook is proposed for future instrumentation indicating a need for highly revolutionized bioaerosol detection technologies.
基金supported by the National Natural Science Foundation of China (61271353 and 60908033)the Natural Science Foundation of Anhui Province (1408085MKL47)
文摘Bioaerosol, an important constituent of the atmosphere, can directly affect light radiation characteristics due to absorption and scattering effects. Current research lacks a reasonable explanation for the extinction abilities of bioaerosols in a broadband. Herein, we measured the reflectance spectra of 12 com m on biomaterials and calculated their complex refractive indexes. The peaks of the imaginary part of the complex refractive indexes are located at wavelengths of approximately 0.7, 2.7, 6.1 and 9.5μm. Based on photographs of the floating structures of bioaerosols, we constructed a model for calculating the extinction abilities of bioaerosols in the wavelength range of 240 nm to 14 (im. Taking AN02 spores as an example, absorption was found to account for more than 90% of the total extinction. In addition, the theoretical calculations and experimental data of transmittance corresponding to the smoke box show that bioaerosol exhibits significant broadband extinction ability from UV to IR bands, which provides new directions for the development of broadband light attenuation materials.
文摘Bioaerosols exhibit significant broadband extinction performance and have vital impacts on climate change,optical detection,communication,disease transmission,and the development of optical attenuation materials.Microbial spores and microbial hyphae represent two primary forms of bioaerosol particles.However,a comprehensive investigation and comparison of their optical properties have not been conducted yet.In this paper,the spectra of spores and hyphae were tested,and the absorption peaks,component contents,and protein structural differences were compared.Accurate structural models were established,and the optical attenuation parameters were calculated.Aerosol chamber experiments were conducted to verify the optical attenuation performance of microbial spores and hyphae in the mid-infrared and far-infrared spectral bands.Results demonstrate that selecting spores and hyphae can significantly reduce the average transmittance from 21.2%to 6.4%in the mid-infrared band and from 31.3%to 19.6%in the far-infrared band within three minutes.The conclusions have significant implications for the selection of high-performance microbial optical attenuation materials as well as for the rapid detection of bioaerosol types in research on climate change and the spread of pathogenic aerosols.
基金Supported by the Fund for Agricultural Science and Technology Independent Innovation of Jiangsu Province[CX(12)1001-05]~~
文摘ObjectiveThis study was to establish a simple method for collecting and detecting Mycoplasma hyopneumoniae （Mhp） in aerosol. MethodBased on the mechanisms of liquid impinger and filtration sampler, a double concentration aerosol sampler was designed for collecting Mhp aerosol. Firstly, the collection was performed in a closed environment full of artificial aerosol of Mhp. Secondly, collection efficiency was detected by real-time PCR. Thereafter, the clinical feasibility of the designed equipment was tested by collecting aerosol samples in different pig herds. In one assay, the samples were collected at different times from one pig house challenged with Mhp. In another assay, the samples was collected from the delivery room, nursery and fattenning house of a MPS outbreak farm as well as a Mhp infection positive pig farm without obvious clinical symptoms. All the aerosol samples were then detected by real-time PCR or nested PCR. ResultThe collection efficiency of the designed bioaerosol sampler was （37.04±6.43） %, Mhp could be detected 7 d after intratracheal challenge with pneumonic lung homogenate suspension. Aerosol samples of 11 pig houses from the two Mhp positive pig farms with or without clinical symptoms all showed a positive result of PCR, the positivity rate was 100%. ConclusionA high sensitive collecting and detecting technology of aerosol was successfully established, which can be applied to clinical detection of Mhp in aerosol.
