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1.
Artigo em Inglês | MEDLINE | ID: mdl-35682227

RESUMO

In this study, the levels of airborne bacteria and fungi were tested in a female dormitory room; the effects of heating, relative humidity and number of occupants on indoor microorganisms were analyzed and the dose rate of exposure to microbes was assessed. The bacterial and fungal concentrations in the room ranged from 100 to several thousand CFU/m3, and the highest counts were observed in the morning (930 ± 1681 CFU/m3). Staphylococcus spp. and Micrococcus spp. were found in the dormitory. When the heating was on, the total bacterial and fungal counts were lower than when there was no heating. Moreover, statistically significant differences were observed for bacterial concentrations during the morning periods between the times when there was no heating and the times when there was heating. The number of occupants had an obvious positive effect on the total bacterial counts. Moreover, RH had no correlation with the airborne fungi in the dormitory, statistically. Furthermore, the highest dose rate from exposure to bacteria and fungi was observed during sleeping hours. The dose rate from exposure to airborne microorganisms in the dormitory was associated with the activity level in the room. These results helped to elucidate the threat of bioaerosols to the health of female occupants and provide guidance for protective measures.


Assuntos
Microbiologia do Ar , Poluição do Ar em Ambientes Fechados , Poluição do Ar em Ambientes Fechados/análise , Bactérias , Monitoramento Ambiental/métodos , Fungos , Habitação
2.
Artigo em Inglês | MEDLINE | ID: mdl-35682253

RESUMO

We aimed to analyze airborne microorganisms and assess air quality, temperature, and relative humidity at "J" Market, an arcade-type traditional market in Anseong (South Korea). Measurements were taken 16 times, twice per quarter (January, April, July, and October), at both the entrance and intersection of the market in 2020. The concentrations of airborne bacteria and fungi at the entrance and intersection were highest in October and lowest in April; however, they were below the recommended indoor levels (airborne bacteria: <800 CFU/m3, airborne fungi: <500 CFU/m3) in January (second measurement) and April (first and second measurements). The concentrations of microbes during the first measurement in January and both measurements in July and October exceeded the allowed limits. The concentration of microorganisms exceeded the acceptable levels at relative humidity ≥60%. At all time points, except during the eighth survey, when the microorganisms were too numerous to count, microbial concentrations were higher at the intersection than at the entrance. It was confirmed that the microorganisms detected in this experiment were 26 species of bacteria and 21 species of fungi. Three of the four species of bacteria and fungi detected in more than 50% of the 16 experimental results were pathogenic. Our findings suggest that air purification systems must be installed in the market to improve sanitary conditions.


Assuntos
Microbiologia do Ar , Poluição do Ar em Ambientes Fechados , Poluição do Ar em Ambientes Fechados/análise , Bactérias , Monitoramento Ambiental , Fungos , República da Coreia
3.
Environ Res ; 212(Pt D): 113597, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35660405

RESUMO

Waste workers are exposed to bioaerosols when handling, lifting and dumping garbage. Bioaerosol exposure has been linked to health problems such as asthma, airway irritant symptoms, infectious, gastrointestinal and skin diseases, and cancer. Our objective was to characterize the exposure of urban collectors and drivers to inhalable bioaerosols and to measured the cytotoxic effect of air samples in order to evaluate their health risk. Personal and ambient air sampling were conducted during the summer of 2019. Workers from 12 waste trucks collecting recyclables, organic waste or compost were evaluated. Bacteria and fungi were cultured, molecular biology methods were used to detect microbial indicators, cytotoxic assays were performed and endotoxins and mycotoxins were quantified. Domestic waste collectors were exposed to concentrations of bacteria and endotoxins above the recommended limits, and Aspergillus section Fumigati was detected at critical concentrations in their breathing zones. Cytotoxic effects were observed in many samples, demonstrating the potential health risk for these workers. This study establishes evidence that waste workers are exposed to microbial health risks during collection. It also demonstrates the relevance of cytotoxic assays in documenting the general toxic risk found in air samples. Our results also suggest that exposures differ depending on the type of waste, job title and discharge/unloading locations.


Assuntos
Poluentes Ocupacionais do Ar , Exposição Ocupacional , Microbiologia do Ar , Poluentes Ocupacionais do Ar/análise , Poluentes Ocupacionais do Ar/toxicidade , Bactérias , Endotoxinas/análise , Endotoxinas/toxicidade , Fungos , Humanos , Veículos Automotores , Exposição Ocupacional/análise
4.
Ecotoxicol Environ Saf ; 240: 113689, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35636240

RESUMO

Airborne E. coli, fecal coliform, and Enterococcus are all related to sewage worker's syndrome and therefore used as target enteric bioaerosols about researches in wastewater treatment plants (WWTPs). However, most of the studies are often inadequately carried out because they lack systematic studies reports bioaerosols emission characteristics and health risk assessments for these three enteric bacteria during seasonal variation. Therefore, quantitative microbial risk assessment based on Monte Carlo simulation was utilized in this research to assess the seasonal variations of health risks of the three enteric bioaerosols among exposure populations (academic visitors, field engineers, and office staffs) in a WWTP equipped with rotating-disc and microporous aeration modes. The results show that the concentrations of the three airborne bacteria from the rotating-disc aeration mode were 2-7 times higher than the microporous aeration mode. Field engineers had health risks 1.5 times higher than academic visitors due to higher exposure frequency. Health risks of airborne Enterococcus in summer were up to 3 times higher than those in spring and winter. Similarly, health risks associated to E. coli aerosol exposure were 0.3 times higher in summer compared to spring. In contrast, health risks associated with fecal coliform aerosol were between 2 and 19 times lower in summer compared to spring and winter seasons. Data further suggest that wearing of N95 mask could minimize health risks by 1-2 orders of magnitude. This research shed light on seasonal variation of health risks associated with bioaerosol emission from wastewater utilities.


Assuntos
Microbioma Gastrointestinal , Purificação da Água , Aerossóis , Microbiologia do Ar , Escherichia coli , Bactérias Gram-Negativas , Humanos , Medição de Risco , Estações do Ano , Águas Residuárias/microbiologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-35627588

RESUMO

The coronavirus disease pandemic has afforded dental professionals an opportunity to reconsider infection control during treatment. We investigated the efficacy of combining extraoral high-volume evacuators (eHVEs) with preprocedural mouth rinsing in reducing aerosol contamination by ultrasonic scalers. A double-masked, two-group, crossover randomized clinical trial was conducted over eight weeks. A total of 10 healthy subjects were divided into two groups; they received 0.5% povidone-iodine (PI), essential oil (EO), or water as preprocedural rinse. Aerosols produced during ultrasonic scaling were collected from the chest area (PC), dentist's mask, dentist's chest area (DC), bracket table, and assistant's area. Bacterial contamination was assessed using colony counting and adenosine triphosphate assays. With the eHVE 10 cm away from the mouth, bacterial contamination by aerosols was negligible. With the eHVE 20 cm away, more dental aerosols containing bacteria were detected at the DC and PC. Mouth rinsing decreased viable bacterial count by 31-38% (PI) and 22-33% (EO), compared with no rinsing. The eHVE prevents bacterial contamination when close to the patient's mouth. Preprocedural mouth rinsing can reduce bacterial contamination where the eHVE is positioned away from the mouth, depending on the procedure. Combining an eHVE with preprocedural mouth rinsing can reduce bacterial contamination in dental offices.


Assuntos
Anti-Infecciosos Locais , Antissépticos Bucais , Aerossóis , Microbiologia do Ar , Anti-Infecciosos Locais/uso terapêutico , Bactérias , Humanos , Antissépticos Bucais/uso terapêutico , Ultrassom
6.
Environ Res ; 212(Pt C): 113425, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35561831

RESUMO

Residential airborne culturable bacteria (RAB) are commonly used to assess indoor microbial loads, which is a very effective and recognized indicator of public concern about residential air quality. Many countries and organizations have set exposure limits for residential bacteria. Nevertheless, few studies have been conducted in multicenter cities about the distribution and influencing factors of RAB. It is a challenge to investigate the distribution of RAB and identify the association between indoor influencing variables and RAB in China. The current finding implied the comparative results from a one-year on-site survey of 12 cities in China. The concentration of RAB ranged from 0 CFU/m3 to 18,078 CFU/m3, with an arithmetic median of 350 CFU/m3. RAB concentrations were more in the warm season than those in the cold season, and were more in the bedrooms than those in the living rooms. Indoor environmental indicators (including PM2.5 and PM10) showed the mediating role in the process of temperature and relative humidity effects on RAB. . Influential factors including family-related information (income), architectural characteristics (house type, building history, living floor, the layers of window glass, and decoration) and lifestyle behaviors (heating, new furniture, incense-burned, insecticides-used, air condition-used, and plants-growed) were related with the concentration of RAB. This study presents essential data on the distribution of RAB in some Chinese cities, and reveals the residential influential factors that might minimize health risk from RAB.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluição do Ar , Microbiologia do Ar , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Bactérias , Cidades , Monitoramento Ambiental/métodos , Estações do Ano
8.
Sci Total Environ ; 838(Pt 1): 155990, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35584754

RESUMO

Dahuting Han Dynasty Tomb, famous for its magnificent and realistic murals in China, was selected for a year-long study as the research target in relation to microbiological degradation of cultural heritage. This dissertation has investigated the predominant genera of the airborne fungal microbial community in Dahuting and analyzed the seasonal distribution characteristics and temporal-spatial particle size distribution of the fungi in a tomb environment. The combination of culture-dependent and high-throughput sequencing methods was utilized for counting the collected fungi and identifying the strains. Results showed that seasonal dynamics significantly affect the fungal concentration, with higher-level concentrations observed in spring and autumn. However, seasonal variation has little effect on the fungal particle size distribution characteristic trend, and the higher concentration invariably appeared in stage IV to VI (0.65-3.3 µm) of the Andersen six-stage sieve impactor. The ITS (Internal Transcribed Spacer) rRNA gene-based sequences disclosed a high airborne culturable fungal abundance, dominated by Talaromyces spp. (20%-38.4%), followed by Aureobasidium spp. (19.4%-25.6%), Penicillium spp. (10.8%-23.9%) and Aspergillus spp. (8.2%-23.1%). Our research provides valuable information for reasonable protection measures and scientific prevention work of the murals in Dahuting Han Dynasty Tomb.


Assuntos
Fungos , Penicillium , Microbiologia do Ar , China , Monitoramento Ambiental/métodos , Fungos/genética , Estações do Ano
9.
Sci Total Environ ; 838(Pt 1): 155969, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35588847

RESUMO

Bioaerosols have become a major environmental concern in recent years. In this study, the diurnal variations and size distributions of bioaerosols, as well as airborne bacterial community compositions and their influencing factors on haze and non-haze days in Xi'an, China, were compared. The results indicated that the mean bacteria and fungi concentrations on non-haze days were 1.7 and 1.4 times of those on haze days, respectively, whereas the mean total airborne microbe (TAM) concentration was higher on haze days. Bacteria concentrations were the lowest in the afternoon, and the TAM concentration exhibited a bimodal distribution with two peaks coinciding with traffic rush hours. On haze days airborne fungi was mainly attached to PM2.5, whereas bacteria and TAM were mainly distributed in coarse PM. The relative abundance of Chao1, Shannon and Simpson indices of bacterial communities were higher in the non-haze day samples, for the reason that high PM2.5 levels with a large specific surface area may absorb more toxic and harmful substances on haze days, which should affect microbial growth. At the generic level, the relative abundance of Rhodococcus, Paracoccus, Acinetobacter, and Kocuria on haze days was higher than that on non-haze days, indicating a higher risk of contracting pathogenic pneumonia. The results of the redundancy analysis revealed that PM2.5 and water-soluble inorganic ions (WSIIs, NO3-, SO42+, and NH4+) strongly affected the bacterial communities on non-haze days, especially Acinetobacter. The atmospheric oxidation capacity (Ox) had a significant effect on bacterial communities during haze episodes, which were positively correlated with Paracoccus, Deinococcus, Sphingomonas, and Rubellimicrobium and were negatively correlated with Rhodococcus. These results provide valuable data to elucidate the formation and evolution of bioaerosol between haze and non-haze events and its potential threats to human health.


Assuntos
Poluentes Atmosféricos , Material Particulado , Aerossóis/análise , Microbiologia do Ar , Poluentes Atmosféricos/análise , Bactérias , China , Monitoramento Ambiental/métodos , Fungos , Humanos , Tamanho da Partícula , Material Particulado/análise , Estações do Ano
10.
Sci Total Environ ; 832: 155033, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35390386

RESUMO

Bioaerosol as an important medium has aroused widespread concern on its potential hazards in disease transmission and environment biosafety. However, little is known about the duration and self-decay of airborne bacteria in the atmosphere environment. Further, the self-decay process is proposed to include biological-decay and physical-decay. At present, there are many reports on the bacteria apoptosis mechanism and airborne particle migration. However, few studies focus on self-decay during the physical movement of airborne bacteria. The present study investigated self-decay laws and efficiencies of airborne bacteria in the sealed reactor under room temperature (18 ± 2 °C, RT) and low temperature (3 ± 2 °C, LT). The self-decay rate constants of 0.0089, 0.0133, 0.0092, and 0.0122 min-1 were obtained under RT-E. coli, LT-E. coli, RT-S. aureus and LT-S. aureus, respectively. There was no significant difference between the self-decay efficiency of gram-negative and gram-positive bacteria under the same conditions. Nevertheless, gram-negative bacteria were more sensitive to temperature change compared with gram-positive bacteria, where the self-decay efficiency of gram-negative under LT was 49% higher than that under RT, and the value of gram-positive was 32% at the same condition. Furthermore, the laws of biological-decay and physical-decay conformed to the first-order kinetic model by theoretical derivation. Biological-decay accounted for 59.5% at RT and 88.5% at LT among self-decay, which is mainly caused by energy absorption, environmental stress, and bacterial structure changes. Physical-decay mainly caused by gravity settlement accounting for 40% at RT and 10% at LT among self-decay, approximately. Meanwhile, the influence of environmental factors on self-decay was mainly reflected in the biological-decay process. Overall, it is of great significance for clarifying the changing laws of bioaerosol and controlling the transmission of airborne bacteria.


Assuntos
Microbiologia do Ar , Escherichia coli , Bactérias , Bactérias Gram-Positivas , Cinética , Staphylococcus aureus , Temperatura
11.
J Hosp Infect ; 125: 48-54, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35452718

RESUMO

BACKGROUND: Adequate storage of sterile surgical devices must prevent contamination and the introduction of microbial contaminants inside the operating room. For functional and economic purposes, stacker cranes (STCs) could replace the traditional sterile storage room (TSSR). STCs are large, multi-stage, computer-assisted systems used to automatically store and retrieve loads from defined locations. However, their microbiological performance has not been evaluated. AIM: As part of the opening of a new building that included an operating theatre, we qualified a new STC and compared its microbiological control performance to that of the previous TSSR. METHODS: From December 2020 to March 2021, 590 environmental specimens (air, N = 56; surfaces, N = 534) were collected and interpreted according to the NF S90-351 French Association for Standardization standards. FINDINGS: Thorough surface disinfection was not sufficient for controlling microbial contamination in the STC. Thus, the initial qualification testing was conducted following an aggressive aerial chemical decontamination of the STC. Despite the lack of a HEPA filtered air system, the overall non-conformity rates were lower in the STC than in the TSSR (8.3% vs 21.4%, P=0.33 for air, respectively, and 9.7% vs 41.7% P<0.001 for surfaces). The air-controlled barrier in front of the loading zone appeared to be sufficient to prevent bacterial contamination. The presence of fungi must be carefully monitored. CONCLUSION: This is the first study supporting the contribution of STCs in saving space and improving the maintenance of sterile surgical device storage and availability under acceptable environmental conditions. Further studies are needed to assess the long-term microbiological contamination inside the STC.


Assuntos
Microbiologia do Ar , Salas Cirúrgicas , Bactérias , Fungos , Humanos
12.
BMJ ; 377: o976, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35418446
13.
Ecotoxicol Environ Saf ; 236: 113478, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35390686

RESUMO

Bioaerosols containing pathogens released from wastewater treatment plants (WWTP) may pose potential health risks to workers on-site and residents downwind. In this study, sampling points were set up in the wastewater treatment facility to investigate the generation pattern of bioaerosols in the aeration tank section. High-throughput sequencing was utilized to assay the intestinal bacteria population, while the health risks associated with airborne bacteria were estimated based on average daily dose rates. The contribution of wastewater to bioaerosols was evaluated using the traceability analysis. As the rotational speed increased from 200 rpm to 800 rpm, the concentration of culturable bacteria increased from 397 CFU/m3 to 1611 CFU/m3, the proportion of bacteria attached to particles with an aerodynamic diameter larger than 4.7 µm increased from 30.41% to 48.44%, and the Shannon index of air samples increased from 1.032485 to 1.282065. Microbial composition, sources, and health risks of bioaerosols also changed as the rotational speed increased. The results showed that the predominant bacteria in the air at 200 rpm were Bacillus (78.78%), Paenibacillus (11.77%) and Lysinibacillus (1.40%). When the rotating speed reached 800 rpm, the dominant bacteria became Bacillus (55.50%), Acinetobacter (31.01%), and Paenarthrobacter (13.17%). The contribution of the wastewater to bioaerosols increased from 46.49% to 65.10%, in which surface water was the main source of bioaerosols (34.64% on average). Although the contribution of bottom water was lower than that of surface water, its contribution increased more, from 15.36% to 29.31%. The health risk of bioaerosols was 1.28 × 10-2 on average, which increased with the increase of rotational speed. At the same exposure concentration, children (2.31 × 10-2) have a higher exposure risk than adults (7.67 × 10-3). This study is aimed at exploring the variation law of bioaerosols discharged from WWTP with oxidation ditch process and providing preliminary data for reducing its risk.


Assuntos
Águas Residuárias , Purificação da Água , Aerossóis/análise , Microbiologia do Ar , Bactérias/genética , Criança , Monitoramento Ambiental , Humanos , Águas Residuárias/microbiologia , Água/análise
14.
Environ Monit Assess ; 194(5): 355, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35403921

RESUMO

Microbiological air contamination in the desert environment is becoming an essential subject for the health of office building occupants and public health. In this study, the concentrations and compositions of airborne microorganisms (bacteria and fungi) were assessed in indoor and outdoor environments using a multistory building complex in Kuwait as a case study. Airborne microorganism samples were collected from 12 sites within the building complex containing nineteen stories over four seasons. Culturable airborne bacteria and fungi were impacted on selected media to determine their concentrations and compositions with a Biolog Omnilog GEN III system and Biolog MicroStation. The indoor mean airborne bacterial count concentrations ranged from 35 to 18,463 CFU/m3, concentrations that are higher than 2,000 CFU/m3, demonstrating high-very high contamination levels in all seasons. Fungal contamination was high in winter and summer, with detected concentrations > 2,000 CFU/m3. Indoor-to-outdoor (I/O) ratios showed that airborne microbial contamination inside building floors originated from indoor air contamination. All the building floors showed bacterial and fungal concentrations ranging from less than 2,000 to more than 2,000 CFU/m3, indicative of a high to very high air contamination level. Statistical analysis showed no correlation between bacterial and fungal concentrations, demonstrating that they originated from unrelated sources. In the indoor building air, the most prevalent bacterial isolate was Bacillus pseudomycoides/cereus, whereas the most dominant fungal isolate was Aspergillus spp. The low count for indoor air bacterial species suggested no particular health risk for the occupants. In contrast, the high count of indoor air fungal species in the winter samples and the presence of potentially allergenic genera detected may suggest possible health risks for the occupants. The results obtained are the basis for the recommendation that the maintenance activities of the HVAC system and the periodical cleaning operation program be revised and preplanned as protective measures.


Assuntos
Microbiologia do Ar , Poluição do Ar em Ambientes Fechados , Poluição do Ar em Ambientes Fechados/análise , Bactérias , Clima Desértico , Monitoramento Ambiental , Fungos , Estações do Ano
15.
J Hazard Mater ; 434: 128873, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35427967

RESUMO

Growth tube collectors (GTCs) are used to sample virus aerosols because of their superior viable virus recovery among air samplers. However, a major limitation of such samplers is that they operate at low flow rates compared to many inertia-based air samplers. Herein, we demonstrated efficient measurements of airborne MS2 and T3 viruses using a GTC that can implement high flow velocities for higher flow rates per tube, which we refer to as the growth-based virus aerosol concentrator (GVC), via qPCR and the plaque assay technique. The GVC exhibited a flow rate of up to 6 L/min, where the average sampling flow velocity was 5.09 m/s, 22 times higher than those used in the GTCs, for a single tube with a diameter of 5 mm. The count median diameter of the size-increased particles at the exit of the initiator was measured to be 1.44 µm at 6 L/min, considerably smaller than those observed in conventional GTCs. Nevertheless, the measurement of airborne MS2 and T3 viruses using the GVC showed a high concentration (high enrichment ratio of 109,458 at 10-min sampling) of viruses in a sampling medium, with a high viable virus percentage (> 90%) and physical collection efficiency (> 90%) at 6 L/min, which shows the potential for rapid on-site detection of airborne viruses.


Assuntos
Microbiologia do Ar , Vírus , Aerossóis/análise , Monitoramento Ambiental/métodos , Tamanho da Partícula
16.
Artigo em Inglês | MEDLINE | ID: mdl-35457694

RESUMO

This study aimed to assess the physicochemical, microbiological and toxicological hazards at an illegal landfill in central Poland. The research included the analysis of airborne dust (laser photometer), the number of microorganisms in the air, soil and leachate (culture method) and the microbial diversity in the landfill environment (high-throughput sequencing on the Illumina Miseq); the cytotoxicity (PrestoBlue) and genotoxicity (alkaline comet assay) of soil and leachate were tested. Moreover, an analysis of UHPLC-Q-ToF-UHRMS (ultra-high-performance liquid chromatography-quadrupole-time-of-flight ultrahigh-resolution mass spectrometry) was performed to determine the toxic compounds and microbial metabolites. The PM1 dust fraction constituted 99.89% and 99.99% of total dust and exceeded the threshold of 0.025 mg m-3 at the tested locations. In the air, the total number of bacteria was 9.33 × 101-1.11 × 103 CFU m-3, while fungi ranged from 1.17 × 102 to 4.73 × 102 CFU m-3. Psychrophilic bacteria were detected in the largest number in leachates (3.3 × 104 to 2.69 × 106 CFU mL-1) and in soil samples (8.53 × 105 to 1.28 × 106 CFU g-1). Bacteria belonging to Proteobacteria (42-64.7%), Bacteroidetes (4.2-23.7%), Actinobacteria (3.4-19.8%) and Firmicutes (0.7-6.3%) dominated. In the case of fungi, Basidiomycota (23.3-27.7%), Ascomycota (5.6-46.3%) and Mortierellomycota (3.1%) have the highest abundance. Bacteria (Bacillus, Clostridium, Cellulosimicrobium, Escherichia, Pseudomonas) and fungi (Microascus, Chrysosporium, Candida, Malassezia, Aspergillus, Alternaria, Fusarium, Stachybotrys, Cladosporium, Didymella) that are potentially hazardous to human health were detected in samples collected from the landfill. Tested leachates and soils were characterised by varied cyto/genotoxins. Common pesticides (carbamazepine, prometryn, terbutryn, permethrin, carbanilide, pyrethrin, carbaryl and prallethrin), quaternary ammonium compounds (benzalkonium chlorides), chemicals and/or polymer degradation products (melamine, triphenylphosphate, diphenylphtalate, insect repellent diethyltoluamide, and drugs (ketoprofen)) were found in soil and leachate samples. It has been proven that the tested landfill is the source of the emission of particulate matter; microorganisms (including potential pathogens) and cyto/genotoxic compounds.


Assuntos
Microbiologia do Ar , Poeira , Bactérias , Poeira/análise , Fungos , Humanos , Polônia , Solo , Instalações de Eliminação de Resíduos
17.
Sci Total Environ ; 831: 154665, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35314242

RESUMO

As a vital component of airborne bioaerosols, bacteria and fungi seriously endanger human health as pathogens and allergens. However, comprehensive effects of environmental variables on airborne microbial community structures remain poorly understood across the PM sizes and seasons. We collected atmospheric PM1.0, PM2.5, and PM10 samples in Hefei, a typical rapidly-developing city in East China, across three seasons, and performed a comprehensive analysis of airborne microbial community structures using qPCR and high-throughput sequencing. Overall the bacterial and fungal abundances in PM1.0 were one to two orders of magnitude higher than those in PM2.5 and PM10 across seasons, but their α-diversity tended to increase from PM1.0 to PM10. The bacterial gene abundances showed a strong positive correlation (P < 0.05) with atmospheric SO2 and NO2 concentrations and air quality index. The bacterial gene abundances were significantly higher (P = 0.001) than fungi, and the bacterial diversity showed stronger seasonality. The PM sizes influenced distribution patterns for airborne microbial communities within the same season. Source-tracking analysis indicated that soils, plants, human and animal feces represented important sources of airborne bacteria with a total relative abundance of more than 60% in summer, but total abundance from the unidentified sources surpassed in fall and winter. Total 10 potential bacterial and 12 potential fungal pathogens were identified at the species level with the highest relative abundances in summer, and their abundances increased with the PM sizes. Together, our results indicated that a complex set of environmental factors, including water-soluble ions in PM, changes in air pollutant levels and meteorological conditions, and shifts in the relative importance of available microbial sources, acted to control the seasonal compositions of microbial communities in the urban atmosphere.


Assuntos
Poluentes Atmosféricos , Microbiota , Microbiologia do Ar , Poluentes Atmosféricos/análise , Animais , Atmosfera/análise , Bactérias , Monitoramento Ambiental , Fungos/genética , Material Particulado/análise , Estações do Ano
18.
Artigo em Inglês | MEDLINE | ID: mdl-35329215

RESUMO

Indoor air quality in hospital operating rooms is of great concern for the prevention of surgical site infections (SSI). A wide range of relevant medical and engineering literature has shown that the reduction in air contamination can be achieved by introducing a more efficient set of controls of HVAC systems and exploiting alarms and monitoring systems that allow having a clear report of the internal air status level. In this paper, an operating room air quality monitoring system based on a fuzzy decision support system has been proposed in order to help hospital staff responsible to guarantee a safe environment. The goal of the work is to reduce the airborne contamination in order to optimize the surgical environment, thus preventing the occurrence of SSI and reducing the related mortality rate. The advantage of FIS is that the evaluation of the air quality is based on easy-to-find input data established on the best combination of parameters and level of alert. Compared to other literature works, the proposed approach based on the FIS has been designed to take into account also the movement of clinicians in the operating room in order to monitor unauthorized paths. The test of the proposed strategy has been executed by exploiting data collected by ad-hoc sensors placed inside a real operating block during the experimental activities of the "Bacterial Infections Post Surgery" Project (BIPS). Results show that the system is capable to return risk values with extreme precision.


Assuntos
Poluição do Ar em Ambientes Fechados , Salas Cirúrgicas , Ar Condicionado , Microbiologia do Ar , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/prevenção & controle , Humanos , Infecção da Ferida Cirúrgica/prevenção & controle
19.
Artigo em Inglês | MEDLINE | ID: mdl-35329300

RESUMO

Home healthcare workers (HHCWs) are subjected to variable working environments which increase their risk of being exposed to numerous occupational hazards. One of the potential occupational hazards within the industry includes exposure to bioaerosols. This study aimed to characterize concentrations of three types of bioaerosols utilizing a novel fluorescence-based direct-reading instrument during seven activities that HHCWs typically encounter in patients' homes. Bioaerosols were measured in an indoor residence throughout all seasons in Cincinnati, OH, USA. A fluorescence-based direct-reading instrument (InstaScope, DetectionTek, Boulder, CO, USA) was utilized for all data collection. Total particle counts and concentrations for each particle type, including fluorescent and non-fluorescent particles, were utilized to form the response variable, a normalized concentration calculated as a ratio of concentration during activity to the background concentration. Walking experiments produced a median concentration ratio of 52.45 and 2.77 for pollen and fungi, respectively. Fungi and bacteria produced the highest and lowest median concentration ratios of 17.81 and 1.90 for showering, respectively. Lastly, our current study showed that sleeping activity did not increase bioaerosol concentrations. We further conclude that utilizing direct-reading methods may save time and effort in bioaerosol-exposure assessment.


Assuntos
Poluição do Ar em Ambientes Fechados , Exposição Ocupacional , Aerossóis/análise , Microbiologia do Ar , Poluição do Ar em Ambientes Fechados/análise , Atenção à Saúde , Monitoramento Ambiental/métodos , Fluorescência , Fungos , Humanos , Exposição Ocupacional/análise
20.
J Hazard Mater ; 429: 128372, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35236040

RESUMO

Cross-transmission of airborne pathogens between buildings facilitates the spread of both human and animal diseases. Rational spatial arrangement of buildings and air inlet-outlet design are well-established preventive measures, but the effectiveness of current configurations for mitigating pathogens cross-transmission is still under assessment. An intensive field study in a laying hen farm was conducted to elucidate the spatial distribution of airborne bacteria (AB) and the source of AB at the inlets under different wind regimes. We found higher concentrations of AB at the interspace and sidewall inlets of buildings with sidewall exhaust systems than at those with endwall exhaust systems. We observed significant differences in bacterial diversity and richness at the interspace and sidewall inlets between buildings with side exhaust systems and those with endwall exhaust systems. We further found that the AB emitted from buildings could translocate to the sidewall inlets of adjacent building to a greater extent between buildings with sidewall exhaust systems than between those with endwall exhaust systems. Our findings revealed that sidewall exhaust systems aggravate cross-transmission of AB between buildings, suggesting that endwall exhaust systems or other compensatory preventive measures combined with sidewall exhaust systems could be a better choice to suppress airborne cross-transmission.


Assuntos
Microbiologia do Ar , Doenças dos Animais , Abrigo para Animais , Doenças dos Animais/transmissão , Animais , Bactérias , Galinhas , Feminino , Vento
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