Aerobiologia最新文献

Some types of airborne pollen can cause pollinosis, and several studies have been conducted on the fluctuation and prediction of their dispersal amount. In Sapporo, Betula pollen is the main cause of hay fever, as in Europe and North America, and various types of pollen other than Betula pollen are dispersed from early spring to autumn. These pollen grains vary in size and shape, and the distribution of their sources is also diverse. In this study, in order to obtain knowledge about the localized pollen dispersion trends within the same city, airborne pollen was comprehensively observed for six years at two sites, one in the center of Sapporo and the other about 10 km away near the mountain area. In addition, stellate hairs, which are airborne substances derived from plants other than pollen, were also observed. Cryptomeria pollen showed the highest correlation between the two sites among all 17 pollen groups. Betula pollen includes three species (B. platyphylla, B. maximowicziana and B. ermanii) that differ in dispersal time, size and distribution of source plants, but it showed a high correlation between the two sites. Although it was revealed that the trends differed depending on the pollen, it is interesting that large pine pollen with air sacs showed high correlation only in the daily fluctuations. We believe that it is useful information that a statistically high correlation was shown between the two locations in both daily and annual fluctuations of Cryptomeria and Betula pollens, which are involved in pollinosis in Japan.

Common ragweed (Ambrosia artemisiifolia) is one of the most harmful alien invasive species in Europe. Ragweed pollen is a potent aeroallergen, and can travel long distances in the atmosphere. In this research we studied pollen samples collected in Turku, Finland, during 1990–2022, to identify when ragweed pollen was first transported to the country and how frequently it has happened since, how much pollen has been transported to the country yearly, and whether it is possible to observe trends in airborne ragweed pollen occurrence in Finland during the past decades. We show that (1) ragweed pollen has been transported to Finland since the 1990’s, significantly earlier than previously thought, and (2) the long-distance transport episodes have often been more intense in the recent years. Ragweed pollen transports occur in the late summer or in the autumn, thus lengthening the pollen season in Finland. We also describe a case study where we show that ragweed is able to produce mature viable seeds in Finland. Our conclusion is that the significance of ragweed as an aeroallergen in Finland is increasing, and thus the situation needs to be regularly monitored.

Pollen allergies affect a large proportion of the UK population, resulting in significant socio-economic costs to the country. The existing Met Office pollen forecast, produced manually, provides a single daily level for 16 UK administrative regions. A new pollen modelling system using the Met Office Numerical Atmospheric-dispersion Modelling Environment (NAME) dispersion model is presented. Initial developments are for the three taxa which are the most allergenic across the UK population: birch, oak and grass. Pollen grain emission maps have been estimated using species distribution modelling methods. The timing of the pollen season is controlled within NAME by an accumulated temperature sum parametrisation, while pollen release is estimated with short-term meteorological dependencies based on precipitation, wind speed, vapour pressure deficit and a diurnal cycle. When examined as hindcasts, the performance of NAME (verified against pollen observations independent of those used in model development) is comparable with the Copernicus Atmosphere Monitoring Service ensemble median prediction for birch and grass. NAME Daily Pollen Index predictions show an improved correlation coefficient (0.58, 0.61) compared to the existing manual forecast (0.53, 0.59) for the years 2022 and 2023, respectively. The NAME model provides taxa-specific outputs at high temporal (hourly) and spatial (0.05°) resolutions, which will eventually transform the level of detail in a future forecast system and therefore be of significantly greater use to the public and health professionals for managing pollen risks.

In urban environments, computational fluid dynamics (CFD) is used for visualizing health and comfort risks in outdoor spaces. Our main objective is to study a model based on 3D trajectories at a local scale, focusing on urban trees geolocated using KML maps and LiDAR data. The study tracks pollen particles (Pinaceae) from trees to pollen samplers, considering meteorological parameters such as wind speed and direction, as well as the influence of buildings. Four simulations were conducted using annual episode criteria, based on representative days from a five-day intradiurnal pollen pattern at both ground and terrace levels. One simulation represented the interannual average, while the others were based on annual averages. The BIM methodology was employed to analyze air quality and particle dispersion. The results from air trajectory simulations and the potential impact of vegetation on buildings (including façade and street canyon effects) could be extrapolated to inform new building designs.

Pathogenic infections especially those caused by organisms resistant to antimicrobials pose a critical challenge to achieving Sustainable Development Goal 3 (SDG 3), particularly in Africa. The environment is also indicated as a significant vector for antimicrobial resistance (AMR) dissemination. Unfortunately, the air is the least monitored environment or reported for AMR. This study reviews the prevalence of bacterial pathogens and resistomes in African air samples, comparing them with global reports. Using PubMed and Google Scholar, publications from 2013 to 2023 on biomonitored air samples were reviewed; the regional occurrence of bacteria, their antibiotic resistance profiles, and the knowledge gaps in this area across the African continent and between other continents are highlighted. West African region had the highest research output and publications, predominantly from Nigeria (46.6%). Most of the African studies focused on indoor air environments, especially in hospitals, employing passive air sampling. Staphylococcus aureus was the most frequently reported bacteria, with tetracycline resistance being the most common. Only three studies in Africa clearly reported antibiotic resistance genes (ARGs) in the air, a stark contrast to the numerous global studies employing molecular methods. The review highlights the lack of indigenous solutions for air treatment and underlines the need for improved surveillance, funding, and policy enforcement to mitigate AMR and strengthen public health systems across the continent.

Birch pollen grains (BPGs) are major aeroallergens in Europe, causing allergies in millions of people. Although background concentrations are provided by stationary pollen monitoring stations, they do not accurately reflect personal exposure. Knowing personal exposure makes it possible to establish a link between inhaled pollen grains and symptoms. Characterizing personal exposure to pollen using portable devices is challenging and requires time-consuming visual counting of pollen grains. We have developed a method for counting sedimented BPGs based on easy sampling using a handheld hoover and automated analysis by gas chromatography-mass spectrometry (GC-MS). This work is a feasibility study on the use of a lipid tracer (heptacosane) for the mass quantification of sedimented BPGs in outdoor and indoor environments. Before a lipid tracer could be used for the determination of BPGs, we ensured that the variability of total lipid mass was low (around 17%) for pollen samples from various geographical origins and for several pollen seasons. The limit of quantification of sedimented BPGs by GC-MS was estimated to be 100 µg (equivalent to 16,000 BPGs), i.e. about 1.6 BPG cm⁻² for a sampled surface of 1 m². This method of assessing individual exposure was implemented during the birch pollen season indoors (between 70 and 225 sedimented BPGs per cm²) and outdoors, directly on the ground under a birch tree (over 6600 BPGs per cm²). This method of counting sedimented pollen grains is suitable for large sample series, and the data obtained could be used as an indicator of individual exposure to indoor air pollen in a large number of patients as part of epidemiological surveys.

Ambrosia artemisiifolia L., or short ragweed, is an invasive species known for its highly allergenic pollen and impact on agriculture. Native to North America, it has spread to northern Türkiye, with models suggesting pollen influx through the Black Sea region. This study had several objectives: (1) to investigate the dynamics and origin of Ambrosia pollen and Amb a 1 allergen emissions in Ankara, a Central Anatolian city with 6 million residents; (2) to examine the effects of meteorological factors on pollen and allergen emissions; (3) to determine the duration of possible risky days for Ambrosia allergy; and (4) to determine the localization of Amb a 1 allergens within the pollen structure using immunolabeling with transmission electron microscopy (TEM). Daily pollen concentrations were obtained using a Burkard spore trap, and Amb a 1 allergen concentrations were measured using a BGI900 high-volume air sampler. Filters capturing PM_>10 and PM_10>2.5 fractions were analyzed via sandwich ELISA. Seasonal Ambrosia pollen indices were 189 in 2015 and 21 in 2016, with allergen concentrations peaking on August 29, 2015 (1620 pg/m³) and August 17, 2016 (201 pg/m³), primarily in PM_>10 fractions. Backward trajectory analysis (HYSPLIT) identified air masses from Ukraine, Crimea and Russia as probable sources, with higher pollen levels linked to northeast and east winds. This is the first study to detail Amb a 1 allergen localization in ragweed pollen. Immunolabeling localized allergens in the pollen wall (columella, cavea and intine) and ribosome-rich cytoplasmic areas, with no labeling observed in starch grains.

The objective of this study was to determine the presence of Drechslera/Helminthosporium in the air of a wheat crop in the NW Iberian Peninsula and its relationship with meteorological variables. Research was conducted in A Limia, Ourense, during the wheat growing seasons from 2021 to 2023. The Lanzoni VPPS-2010 spore trap was used to collect the spores, which were identified by optical microscopy. The phenological stages of the wheat crop were classified according to the BBCH scale, and the spore concentrations in each phenophase were analyzed. Meteorological variables were provided by a meteorological station located near the spore trap. In 2021, monitoring was done for 94 days, in 2022 for 89 days and in 2023 for 78 days. Spores were detected during most phenological stages, mainly during 11–20 h. Temperature and sunshine hours were the variables that positively influenced the variations in Drechslera/Helminthosporium concentrations in the air in 2021 and 2023, while in 2022, relative humidity, rainfall and leaf moisture were the factors that had the most influence. The maximum temperature and leaf moisture of the previous days were the variables that best predicted the concentrations of these spores for 2022. This is the first investigation in Spain that reports the presence of the sporal type Drechslera/Helminthosporium in the air during all phenological stages of wheat cultivation, and provides useful information for the development of strategies to prevent the diseases they cause.

Real-time bioaerosol monitoring is improving the quality of life for people affected by allergies, but it often relies on deep learning models which pose challenges for widespread adoption. These models are typically trained in a supervised fashion and require considerable effort to produce large amounts of annotated data, an effort that must be repeated for new particles, geographical regions, or measurement systems. In this work, we show that self-supervised learning and few-shot learning can be combined to classify holographic images of pollen grains using a large collection of unlabelled data and only a few identified particles per type. We first demonstrate that self-supervision on pictures of unidentified particles from ambient air measurements enhances identification even when labelled data are abundant. Most importantly, it greatly improves few-shot classification when only a handful of labelled images are available. Our findings suggest that real-time bioaerosol monitoring workflows can be substantially optimized, and the effort required to adapt models for different situations considerably reduced.

This study investigates the impact of geographic location on birch and grass pollen seasons in Akureyri, Iceland, and Kraków, Poland, during the years 1998–2023 highlighting the significant variations in pollen dynamics due to differing climatic conditions. Wind-dispersed (anemophilous) pollen is not only crucial for plant reproduction but also a prominent trigger for allergic diseases affecting a large portion of the global population. We analyzed atmospheric pollen concentrations alongside meteorological variables to assess the timing, duration, and intensity of pollen seasons in both locations over the period 1998–2023. Results indicate that birch pollen seasons are more sensitive to meteorological factors, including temperature and precipitation, than grass pollen seasons. In Akureyri, both birch and grass pollen seasons demonstrate greater responsiveness to environmental changes, with complex interactions involving preceding weather conditions. In contrast, Kraków exhibits a more stable climate, with clearer correlations between meteorological variables and pollen production. This comparative analysis reveals that while Kraków grass pollen seasons are predominantly influenced by temperature, Akureyri dynamic weather leads to more variability in pollen season characteristics. Understanding these differences is essential for predicting future changes in pollen exposure and their implications for public health, particularly in light of climate change. Our findings emphasize the need for localized research to unravel the intricate relationships between geographic location, climate variability, and pollen season characteristics, providing valuable insights for managing allergic diseases related to pollen exposure.

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