Aerobiologia最新文献

Passenger air transport is a significant vector for the global dissemination of pathogenic microorganisms. Therefore, evaluating indoor air quality (IAQ) in aircraft cabins is critical for ensuring a safe environment for passengers and crew. This study retrospectively assessed IAQ in commercial aircraft operating at Maceió International Airport, focusing on the microbiological characterization of cabin air through quantifying and identifying airborne bacteria and fungi. Air samples were collected while aircraft were grounded, specifically from the cockpit and the central cabin aisle. Domestic and international flights were included, and analyses adhered to the Brazilian standard NBR 17037. Bioaerosols were sampled using a portable bioaerosol sampler. Fungi were identified via macroscopic and microscopic traits, while bacteria were identified using genetic markers. A diverse fungal population was detected, predominantly Aspergillus and Penicillium spp. Mycotoxin screening yielded positive results in three fungal isolates. Potentially pathogenic bacteria were identified, including Acinetobacter spp., Stutzerimonas stutzeri, Pseudomonas oryzihabitans, and Pantoea dispersa. Results suggest that indoor sources predominantly influence bacterial concentrations, whereas outdoor air significantly contributes to airborne fungal presence. Temperature and relative humidity had a greater effect on fungal bioaerosols than bacterial ones, although further investigation is needed to clarify these relationships. This is the first Brazilian study to assess IAQ in commercial aviation, highlighting the need to continuously monitor microbial contamination in aircraft cabins to mitigate potential health risks.

Indoor air quality is significantly compromised by the biodeterioration of building materials, such as oil-based paints, which facilitates the release of fungal bioaerosols posing health risks to occupants. This study examines the role of Cladosporium sphaerospermum as a key airborne contaminant in paint degradation and evaluates metal nanoparticles as antimicrobial additives to mitigate associated bioaerosol emissions. Cladosporium sphaerospermum was isolated from deteriorated oil-based paint samples and identified via phenotypic and genotypic analyses. Microscopic evaluations, including stereomicroscopy, light microscopy, and scanning electron microscopy (SEM), confirmed its primary involvement in paint degradation through surface invasion and colonization. The fungus displayed robust lipase and urease activities, with specific activities of 43.2 and 824 units per milligram protein, respectively, indicating enzymatic breakdown of paint components. Indoor air quality assessments identified C. sphaerospermum as the predominant bioaerosol in environments with degraded paint, accounting for 69.8% of the total fungal count (128 CFU/m³), followed by Aspergillus niger at 11.7%. Incorporation of silver nanoparticles (Ag-NPs; 3–60 nm particle size) and zinc oxide nanoparticles (ZnO-NPs; 18.2 nm particle size) into oil-based paints markedly improved resistance to fungal deterioration in vivo, relative to controls. These results underscore Ag-NPs and ZnO-NPs as effective additives for enhancing paint longevity and reducing fungal bioaerosol contamination in indoor settings, particularly from C. sphaerospermum and related dematiaceous fungi.

Exposure to fungal spores is associated with various types of respiratory health problems, and volumetric suction particle samplers have been used to estimate their concentrations in the atmosphere. This systematic review analyzes the sampling of fungal spores in outdoor air worldwide and its relationship to epidemiological data on respiratory disease. Ninety-four studies were identified that met the following inclusion criteria: They were original studies published in English or Spanish between 2010 and 2024, used active volumetric impact samplers, and identified the type of fungal spores in air. Most of the studies were conducted in Europe, with a duration of 1 to 2 years. The fungal taxa with the highest records were Alternaria sp. and Cladosporium sp. Only 13% of the studies correlated fungal spore concentrations with epidemiological variables; however, 77% of these studies concluded that there is a clear relationship between airborne fungal spore concentration and the occurrence of respiratory symptoms in the sensitized population. Therefore, this study provides an elaborate review of recent airborne fungal spore surveillance issues worldwide, attempting to include different perspectives of recent research on outdoor volumetric sampling, including epidemiological analysis.

In this study, dominant airborne pollen in the province of Muğla, which is one of the important tourism centers and is located on the Aegean Sea coast of Turkey, was investigated for the first time using the volumetric method. In this two-year study conducted between February 01, 2014, and January 31, 2016, the annual pollen integral (APIn) was recorded as 20,524 pollen*day/m³ in the first year (2014) and 15,041 pollen*day/m³ in the second year (2015). The taxa Pinaceae, Quercus, Olea europaea, Cupressaceae/Taxaceae, and Poaceae accounted for 86.52% of the APIn in 2014 and 77.73% in 2015. The airborne pollen concentration of Pinaceae constituted approximately half of all pollen types (46.28%). In addition to the dominant airborne taxa, Plantago, Urticaceae, Amaranthaceae, Rumex, and Morus pollen grains were also identified as important pollen types in the Muğla atmosphere. The most significant meteorological factors on the airborne concentrations of the dominant taxa within the period of the study included mean temperature and total precipitation. An increase in mean temperature had a positive effect on Olea europaea, Quercus, and Cupressaceae/Taxaceae pollen concentrations, while it had a negative effect on Poaceae pollen concentration. Similarly, total precipitation had a negative effect on airborne concentrations of all dominant pollen types. On the other hand, wind speed did not show a significant effect on pollen concentration. April, during which 44.40% of the total pollen was recorded over the two-year period, was identified as the month posing the highest risk for sensitized individuals living in the region.

Pollen allergies pose a growing public health concern, with their severity and distribution influenced by complex seasonal and climatic factors. More than 30% of Japanese adults are allergic to the pollen released by Japanese cedar trees during spring. Although higher summer temperatures have been found to increase pollen dispersal the following spring, the broader influence of year-round meteorological conditions, including temperature, rainfall, and sunshine duration, on pollen dispersal remains poorly understood. This study investigated the impact of temperature, rainfall, and sunshine duration on pollen deposition from Japanese cedar trees at 109 monitoring stations across Japan between 1986 and 2023. We conducted regression analyses using monthly deviations of meteorological parameters with annual total pollen count and the first pollen deposition date as outcome variables. Our results indicate that higher summer temperatures are associated with increased pollen counts in the following year, whereas higher autumn temperatures are associated with reduced pollen counts. Specifically, a 1 °C increase in mean summer (July to September) temperature was associated with a 39.2% (95% CI: 21.9%, 59.0%) increase in annual pollen count, whereas a 1 °C increase in autumn (October to December) temperature was associated with a 12.8% (95% CI: − 22.5%, − 1.9%) decrease. In addition, higher winter rainfall was correlated with reduced pollen counts, and a longer sunshine duration during summer was associated with both an earlier onset and a larger amount of pollen deposition. These findings underscore the importance of considering how meteorological conditions across years influence pollen deposition in various regions when evaluating the potential effects of climate change on human health through pollen exposure.

Serratia marcescens is widely used as a model strain in aerobiological researches for its apparent colony morphology and easy removablilty from the working environment. In contrast, Bacillus subtilis var. niger ATCC 9372 is highly resistant to environmental stresses, so requires a laboring decontamination process after test. To substitute for this traditional test strain in the biological testing of Class II Biosafety Cabinets (BSC), we evaluated the characteristics of S. marcescens bioaerosol including count median diameter (CMD), the ratio of single cells, and the total viable CFU (Colony forming unit) stability. When the suspension of the S. marcescens for bioaerosol production was prepared via shake culture, the CMD of S. marcescens bioaerosol was 1.72 μm, the ratio of single cells was 92.6%, in accordance with the NSF/ANSI 49 standards. However, the total viable CFU of the S. marcescens bioaerosol tended to decline when prolonged storage of the primary slant culture and the suspension. S. marcescens bioaerosol might be used as a test strain for the biological testing of BSC only when the suspension is prepared using shake culture with a predetermined storage duration of the primary slant culture and the suspension. The relative accuracy, relative specificity, and relative sensitivity of this alternative method using S. marcescens bioaerosol was 92.6%, 91.7%, and 93.3% in personnel protection, 92.6%, 87.5%, and 94.7% in product protection of the biological testing of BSC when compared with the standard method using B. subtilis var. niger.

Ambrosia artemisiifolia (common ragweed), an annual plant native to North America, is an invasive species in Europe, including Poland, posing economic issues and significant health risks due to its highly allergenic pollen. In Poland, common ragweed is still relatively sparsely distributed, but the number of persistent populations has recently increased. This study aimed to check whether an invasion of common ragweed observed since 2020 in Kraków (southern Poland) affected the pollen seasons in the following years. The aerobiological study has been supported by an ongoing botanical survey during which 38 new sites have been described. The local invasion of A. artemisiifolia populations has noticeably affected the recorded pollen seasons since 2020, increasing the risk of exposure for residents, mainly due to the proximity of residential and recreational areas to the largest populations of common ragweed. However, trend analysis did not show the significant long-term tendencies for the most pollen season parameters; SPIn value and the number of high-pollen days increased evidently within the study period. Local ragweed invasion is becoming an increasingly important source of pollen, although pollen exposure from the long-distance transport (LDT) episodes in southern and eastern regions continues to be a large source of pollen.

Airborne pollen is a significant cause of allergies leading to various discomforting symptoms. Many cities worldwide, including Beijing, face airborne pollen challenges. Accurate forecasting of airborne pollen levels can provide critical risk alerts for residents. However, existing studies at urban scale often overlook the spatial variability of pollen levels, focusing predominantly on pollen from individual plant sources or using station-based forecasts, which limits their applicability. To address these shortcomings with available data, this study integrates the Hybrid Single-Particle Lagrangian Integrated Trajectory model with Random Forest to develop a novel method for predicting the spatial distribution of next-day pollen indexes derived from dominant tree species. Using Beijing as a case study, the proposed method demonstrates promising prediction accuracy, with R² of 0.67 for the city-averaged index. An analysis of pollen index distributions during Beijing's spring pollen season reveals that urban areas consistently exhibit higher predicted pollen indexes for the included tree species compared to the citywide average throughout the season. This trend suggests an elevated allergy risk in urban regions from these specific pollen types, likely due to pollen accumulation in semi-enclosed terrains influencing pollen transport and deposition. Furthermore, the study highlights that eliminating the included dominant tree pollen sources in city centers is insufficient to achieve significant reductions in the predicted urban pollen index. This research presents a new approach for generating spatially resolved pollen index forecasts, offering enhanced spatial detail compared to traditional station-based method, and enhanced spatial detail based on available operational data and dominant vegetation surveys, offering valuable insights for allergy prevention strategies.

Atmospheric bioaerosol sampling is being extensively conducted in Antarctica. In this study, bioaerosol sampling was conducted at a 900-m altitude over S17 Base in the coastal region of Antarctica using an unmanned aerial vehicle (UAV) on January 10, 2019. Based on the meteorological data collected using the UAV, bioaerosol samples were obtained from a high mixed layer and/or the low free troposphere. Bacteria belonging to the class Chloroplast were detected in the upper air. Those were also observed at an altitude of about 1000 m over Syowa Station in 2013 (Kobayashi, 2022a), suggesting that they may be persistent in the upper atmosphere over East Antarctica. In the upper air, bacteria belonging to the genera Arcobacter, Finegoldia, and Methyloversatilis were particularly detected. From backward trajectory analyses of the air mass, these bacteria may have been transported long distance.

Background

Exposure to airborne dust particles increases the risks of respiratory illnesses, including asthma, chronic obstructive pulmonary disease, and bronchitis. Determining effective interventional strategies to mitigate toxicity induced by airborne dust particles may provide essential public health benefits. This study assessed the detrimental effects of airborne dust particles extracted from car air filters in Lahore City, alongside the therapeutic potential of adipose-derived stem cell conditioned medium (ADSC-CM) on cabin air filter (CAF) dust-induced lung damage in mice.

Methods

BALB/c mice were subjected to repeated intraperitoneal sensitization with CAF dust suspension followed by challenges with aerosolized dust in a nebulization chamber. Moreover, the treated group of mice received intravenous injections of ADSCs-CM before exposure to CAFs dust challenges. Subsequently, allergic manifestations, lung histopathological features, synthesis of inflammatory cytokines, and potential gene expressions linked to pulmonary diseases were investigated.

Results

CAF dust exposure triggered lung injury and inflammation characterized by epithelial sloughing, hyperplasia, pulmonary edema, and infiltration of inflammatory cells into the bronchi. Further studies showed an increased synthesis of inflammatory cytokines, notably IL-6 and TNF-α, and elevated expression of COX-2 and MUC5AC gene. Supplementation with ADSCs-CM substantially ameliorated lung inflammation, reduced allergic symptoms, induction of cytokines, COX-2, and MUC5AC genes expression.

Conclusion

CAF dust samples showed harmful effects on lung health, depicting potential risks to city residents. The results exhibited that ADSCs-CM transplantation substantially reduced lung inflammation and could serve as a promising treatment for pulmonary disorders.