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Although Svalbard archipelago is considered as a natural laboratory for the environmental studies in the High Arctic, the knowledge on the transport and diversity of bioaerosols (aeroplankton) in the atmosphere is poorly recognized. To improve our knowledge about the aeroplankton over the Svalbard, we conducted a short-term study in the central part of the archipelago with a special focus on two important, but understudied in this region, airborne components: pollen grains and invertebrates. Aerobiological traps, three impact-type samplers and 12 pitfall-type water traps, were operated for a week of July 2022 at three sites located near Longyearbyen, the largest settlement of Svalbard. These sites, that is, Platåfjellet, Longyearbreen Glacier, and glacier valley, varied in the local sources of biological material and altitude. In total, 11 pollen taxa were isolated from pollen impactors. Most of them (68%) belonged to non-native plants, for example, Alnus sp., Betula sp., Picea abies, or Pinus sylvestris-type pollen. In pitfall-type water traps, we found invertebrates representing Acari (Prostigmata, Endeostigmata and Oribatida), Collembola (Agrenia bidenticulata), Tardigrada (Eutardigrada) and Rotifera (Bdelloidea). The most taxa-rich site, both for pollen and invertebrates, was Platåfjellet, characterized by open landscape dominated by small cryptogams, mainly lichens and mosses, and sparse patches of vascular plants. Even though our sampling was short-term, we found diverse taxa belonged to native and alien species, indicating that both local and long-range transport shape aeroplankton composition and seeding of Arctic habitats. Long-term aerobiological monitoring in diverse ecosystems of Svalbard is needed to understand spatio-temporal influence of aeroplankton on ecosystems. [ABSTRACT FROM AUTHOR]

Fungal fragments are abundant immunoreactive bioaerosols that may outnumber the concentrations of intact spores in the air. To investigate the importance of Alternaria fragments as sources of allergens compared to Alternaria spores, we determined the levels of Alternaria spores and Alt a 1 (the major allergen in Alternaria alternata spores) collected on filters within three fractions of particulate matter (PM) of different aerodynamic diameter: (1) PM >10 , (diameter>10 μm); (2) PM 2.5-10 (2.5–10μm); (3) PM 2.5 (0.12–2.5 μm). The airborne particles were collected using a three stage high-volume ChemVol cascade impactor during the Alternaria sporulation season in Poznań, Poland (30 d between 6 July and 22 September 2016). The quantification of Alt a 1 was performed using the enzyme-linked immunosorbent assay. High concentrations of Alt a 1 were recorded during warm and dry d characterized by high sunshine duration, lack of clouds and high dew point values. Atmospheric concentrations of Alternaria spores correlated significantly (r = 0.930, p < 0.001) with Alt a 1 levels. The highest Alt a 1 was recorded in PM 2.5-10 (66.8 % of total Alt a 1), while the lowest in PM 2.5 (<1.0 %). Significantly more Alt a 1 per spore (>30 %) was observed in PM 2.5-10 than in PM >10. This Alt a 1 excess may be derived from sources other than spores, e.g. hyphal fragments. Overall, in outdoor air the major source of Alt a 1 are intact Alternaria spores, but the impact of other fungal fragments (hyphal parts, broken spores, conidiophores) cannot be neglected, as they may increase the total atmospheric Alt a 1 concentration. Image 1 • Alt a 1 (major allergen of Alternaria) was quantified in different air fractions. • Alternaria spores and Alt a 1 levels correlated significantly (r = 0.930, p < 0.001). • The highest Alt a 1 level was detected in PM 2.5-10 , while the lowest in PM 2.5 • Significantly more Alt a 1 per spore (31.3 %) was observed in PM 2.5-10 than in PM >10. • Spores are the main source of Alt a 1, but the impact of hyphae cannot be neglected. [ABSTRACT FROM AUTHOR]

The concentration of fungal spores in the air is traditionally considered as a proxy of allergen exposure. However, in vitro experiments have shown that the allergenicity of Alternaria spores varies depending on ecophysiological and developmental factors. Despite the potential clinical significance of these findings, it has never been verified in outdoor environments. This study, therefore, aims to investigate variability in the amount of the major allergen (Alt a 1) released from Alternaria spores in outdoor air. During the 3-year monitoring study (2014–2016), the median seasonal allergenicity of Alternaria spores exceeded 8.6 × 10−3 pg Alt a 1/spore. The most allergenic spores were collected during the driest and the most polluted season (with respect to seasonal concentrations of ozone, sulphur dioxide, and particulate matter). Within the season, daily spore allergenicity ranged from 2.4 to 34.7 × 10−3 pg Alt a 1/spore (5th-95th percentile). No repeatable effects of weather and pollution on short-term variations in Alternaria spore allergenicity were found. However, during the episodes when high-potency spores were recorded, the air masses arrived from eastern directions. Contrary, the spores with the lowest allergenicity were related to western winds. This suggests that factors such as source area (habitat types) and species diversity could be responsible for the varying exposure to Alternaria allergens. Our findings show that high and low-potency spores are recorded in the air; therefore, the airborne concentrations of fungal spores alone may not be sufficient to provide allergy sufferers and healthcare professionals with information about allergen exposure. [ABSTRACT FROM AUTHOR]

Abstract Due to the urban heat island effect, the time of plant pollination might markedly vary within the area of a city. However, existing pollen forecasts do not reflect the spatial variations in the pollen release time within a heterogeneous urban environment. The main objective of this study was to model the spatial pattern of flowering onset (and thus the moment of pollen release) in silver birch (Betula pendula Roth.) in Poznań (Western Poland) using land surface temperature (LST) data and in situ phenological observations. The onset of silver birch flowering was observed at 34 urban and rural sites (973 trees) in Poznań from 2012 to 2014. Forty-four thermal variables were retrieved from MODerate Resolution Imaging Spectroradiometer (MODIS) data. To predict the spatio-temporal distribution of B. pendula flowering onset dates in a city, the ordinary and partial least squares, support vector machine and random forest regression models were applied. The models' performance was examined by an internal repeated k -fold cross-validation and external validation with archival phenological data (2010). Birch flowering began significantly earlier in the urban sites compared to the rural sites (from −1.4 days in 2013, to −4.1 days in 2012). The maximum March LST difference between the urban and rural sites reached 2.4 °C in 2013 and 4.5 °C in 2012. The random forest model performed best at validation stage, i.e. the root mean square error between the predicted and observed onset dates was 1.461 days, and the determination coefficient was 0.829. A calibrated model for predicting the timing of flowering in a heterogeneous city area is an important step in developing a fine-scale forecasting system that can directly estimate pollen exposure in places where allergy sufferers live. Importantly, by incorporating only pre-flowering thermal data into the model, location-specific allergy forecasts can be delivered to the public before the actual flowering time. Graphical abstract Unlabelled Image Highlights • Birch flowering onset was modelled by machine learning at fine spatial scale (1 km). • In situ flowering data were combined with land surface temperature (LST) data. • LSTs were obtained using Landsat and MODIS remote sensing satellite data. • The random forest model showed the highest quality (R2 = 0.829, RMSE = 1.461 days). • Developed model accurately predicts the flowering onset in heterogeneous city areas. [ABSTRACT FROM AUTHOR]

Introduction: The role of long-distance transported (LDT) Ambrosia pollen in inducing new sensitization and affecting sensitization rates in Artemisia-sensitized patients is unclear. Aim: The aim of this study was to estimate the degree of cross-sensitization to Ambrosia/Artemisia allergens in citizens of Poznan (Western Poland). This area is covered by extensive Artemisia populations but does not currently have local Ambrosia populations. Material and methods: Sera of 119 patients were tested by fluoroenzyme immunoassay (CAP-FEIA system) against pollen allergen extracts of Artemisia vulgaris and Ambrosia artemisiifolia, an allergenic component of A. vulgaris (nArt v 1), and an allergenic component of A. artemisiifolia (nAmb a 1). Skin prick tests (SPTs, n = 86) were performed with pollen allergen extracts of A. vulgaris and A. artemisiifolia. Artemisia and Ambrosia pollen in ambient air was collected (1996-2013) by a Hirst type volumetric trap sited at roof level (33 m). Results: The SPT showed that the prevalence of sensitization to Ambrosia and Artemisia pollen exceeded 3.5%, and 10.5%, respectively. The measurements of IgE in blood serum (CAP-FEIA) revealed that among Ambrosia-sensitized patients 90.1% (20/22 patients) were concomitantly sensitized to Artemisia. 59.1% (13/22) of these patients reacted to nArt v 1, suggesting primary sensitization to Artemisia pollen. Only 2 (9.1%) patients were mono-sensitized to Ambrosia pollen extract, but surprisingly not to nAmb a 1. Conclusions: The LDT Ambrosia pollen had a negligible effect on the rate of sensitization to Ambrosia allergens in Poznan and did not increase the prevalence of sensitization to Artemisia pollen in this region. However, the majority of patients showing hypersensitization to Artemisia pollen might also present symptoms during elevated episodes of LDT of Ambrosia pollen. [ABSTRACT FROM AUTHOR]

The invasive alien species Ambrosia artemisiifolia (common or short ragweed) is increasing its range in Europe. In the UK and the Netherlands, airborne concentrations of Ambrosia pollen are usually low. However, more than 30 Ambrosia pollen grains per cubic metre of air (above the level capable to trigger allergic symptoms) were recorded in Leicester (UK) and Leiden (NL) on 4 and 5 September 2014. The aims of this study were to determine whether the highly allergenic Ambrosia pollen recorded during the episode could be the result of long distance transport, to identify the potential sources of these pollen grains and to describe the conditions that facilitated this possible long distance transport. Airborne Ambrosia pollen data were collected at 10 sites in Europe. Back trajectory and atmospheric dispersion calculations were performed using HYSPLIT_4. Back trajectories calculated at Leicester and Leiden show that higher altitude air masses (1500 m) originated from source areas on the Pannonian Plain and Ukraine. During the episode, air masses veered to the west and passed over the Rhône Valley. Dispersion calculations showed that the atmospheric conditions were suitable for Ambrosia pollen released from the Pannonian Plain and the Rhône Valley to reach the higher levels and enter the airstream moving to northwest Europe where they were deposited at ground level and recorded by monitoring sites. The study indicates that the Ambrosia pollen grains recorded during the episode in Leicester and Leiden were probably not produced by local sources but transported long distances from potential source regions in east Europe, i.e. the Pannonian Plain and Ukraine, as well as the Rhône Valley in France. [ABSTRACT FROM AUTHOR]

The aim of the study was to determinate whether Artemisia campestris was present in the vicinity of 8 pollen monitoring stations in Poland by examining temporal variations in daily average airborne Artemisia pollen data recorded by Hirst type volumetric traps. Three day moving averages of airborne Artemisia pollen were examined by Spearman's rank correlation test. Results show that Artemisia pollen seasons in Poland generally display similar unimodal patterns (correlation coefficients r > 0.900; P < 0.05). The only exception was the Artemisia pollen concentration noted in the outskirts of Poznań (Morasko), where the bimodal pattern was revealed. Correlations between Artemisia pollen data recorded at Poznań-Morasko and the other Polish sites were the lowest in the investigated dataset; this was particularly noticeable in the second part of pollen season (r ~0.730). We show that the typical bimodal pattern in Artemisia pollen seasons, which is characteristic of the presence of both A. vulgaris (first peak) and A. campestris (second peak), does not occur at the majority of sites in Poland and is restricted to the outskirts of Poznań. In fact, it was noted that the pollen monitoring site in Poznań-Centre, just 8 km from Morasko, only exhibited one peak (attributed to A. vulgaris). This shows that the influence of A. campestris on airborne pollen season curves is limited and can be largely disregarded. In addition, this study supports previous records showing that the spatial distribution of airborne Artemisia pollen within a city (urban-rural gradient) can vary markedly, depending on the species composition. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agrobotanica is the property of Polish Botanical Society / Polskie Towarzystwo Botaniczne and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agrobotanica is the property of Polish Botanical Society / Polskie Towarzystwo Botaniczne and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There has only been one study on the ecology of testate amoebae from Amazonian peatlands, despite Amazonia being a biodiversity hotspot of global importance. During analysis of litter samples from Aucayacu peatland, western (Peruvian) Amazonia, we discovered a testate amoeba with a distinct morphology unlike any other species reported previously. We describe a new species, Arcella peruviana , based on its distinct morphology, compare it to morphologically similar species and provide information about its ecology. This new species is characterised by a distinct cruciform aperture (diameter ranges between 12 and 17 μm) which is slightly invaginated. The test is small (height 43–57 μm) and polygonal in cross-section. Our discovery suggests the existence of an unknown diversity of testate amoebae in Amazonia. The absence of the new Arcella species in more intensively-sampled regions supports the view that protists have restricted distributions. [ABSTRACT FROM AUTHOR]

Background. In Central Europe, hazel (Corylus sp.) pollen is considered to be an important aeroallergen in early spring. Objective. This study examines hazel pollen levels in Poznań, western Poland, and the clinical relevance of this aeroallergen in the city. Methods. Corylus pollen data (1996-2010) were obtained by volumetric spore trap located near the centre of Poznań. Clinical data (2006-2010), i.e. skin prick test (SPT) and allergen-specific IgE measurements (asIgE), were supplied by the Allergy Diseases Diagnostic Centre in Poznań. Results. Mean diurnal hazel pollen concentrations peaked around 14:00-16:00 when mean bi-hourly pollen concentrations were ~60 P m(-3). Onset of the hazel pollen season varied up to 87 days annually, and was significantly (r=-0.647; p<0.01) related to mean maximum temperature during late December. SPT data revealed that ~11% of allergy patients had positive skin reactions to Corylus pollen allergens, and most of these (94.4%) reacted to pollen allergens from other members of the Betulaceae family - alder or birch. Of those sensitized, 53% suffered from atopic dermatitis. Of patients examined for serum asIgE, 26.0% had asIgE measurements in classes 5 and 6. Conclusions. Hazel pollen has a detrimental effect on the allergic population of Poznań, with more than half of those sensitised to hazel pollen allergens showing symptoms of atopic dermatitis. Hazel pollen concentrations reach levels recognized as being able to induce allergy symptoms, especially in the afternoon and early evening when many people are returning home from work. The cross-reactivity with other members of the Fagales order also increases the allergenic potential of hazel pollen. [ABSTRACT FROM AUTHOR]

Birch (Betula) pollen seasons were examined in relation to meteorological conditions in Poznań (1996–2010). Birch pollen grains were collected using a volumetric spore trap. An alternate biennial cycle of birch pollen season intensity was noticed in Poznań. The main factors influencing birch pollen season intensity were average daily minimum temperatures during the second fortnight of May and the month of June one year before pollination as well as the intensity of the pollen season of the previous year. Most of the pollen grains are recorded during the first week of the season; the number of pollen grains recorded at this time is positively correlated with mean maximum temperature and negatively correlated with daily rainfall. The significant effect of rainfall in reducing the season pollen index was noticed only during weak pollen seasons (season pollen index < mean). In addition, mean daily maximum temperature during the first two weeks of the birch pollen season markedly influences its duration. No significant trends in duration and intensity of the pollen season were recorded, however, a slight tendency towards early pollination was observed (−0.4 days/year, p = 0.310). [ABSTRACT FROM AUTHOR]

Introduction: Platanus is an ornamental tree commonly planted in the cities. In recent years the number of plane trees in Poznan has markedly increased. Because of the high allergenicity of plane tree pollen, the current tendency to plant a lot of young Platanus trees in Poznan seems to be disturbing. Aim: The main aim of this study was to prepare a map presenting zones of the highest allergic risk of plane tree pollen in Poznan. Material and methods: Daily average Platanus pollen counts (2005-2009) were collected in Poznan by two volumetric pollen traps located both in the city center and on the outskirts of Poznan. The field study of the distribution of Platanus trees in Poznan was conducted during three years (2008-2010). Results:The Platanus pollen season usually starts atthe end of April and lasts for about 3 weeks. The highest pollen level was observed in the city center between 14.00 and 16.00 h. Trace quantities of pollen were detected on the outskirts of Poznan. Over 50 Platanus populations with a number of trees > 20 have been found mainly in the city center. The total number of specimens exceeded 1500, including 448 mature regularly flowering trees. Conclusions: Plane tree pollen exceeded the risk concentrations (> 50 P/m3) only for few days, however during the intensive pollen season the pollen level can easily reach very high values. On the outskirts of Poznan, the pollen level is too low to induce allergic reactions. In recent years, over 1000 of new Platanus trees have been planted. Pre-sumably, along with maturation of these young specimens, the exposure to plane pollen in the city will also increase. [ABSTRACT FROM AUTHOR]

The objectives of this paper are to ascertain the main factors involved in the phenological mechanism of alder flowering in Central Europe by understanding the influence of the main meteorological parameters, the North Atlantic Oscillation (NAO) effect and the study of the Chill and Heat requirements to overcome dormancy. Airborne pollen (1995-2007) was collected in Poznań (Poland) by means a volumetric spore trap. Temperatures for February, and January and February averages of the NAO are generally key factors affecting the timing of the alder pollen seasons. Chilling accumulation (which started in Poznań at the beginning of November, while the end took place during the month of January) of 985 CH with a threshold temperature of -0.25°C, followed by 118 GDD°C with a threshold temperature of 0.5°C, were necessary to overcome dormancy and produce the onset of flowering. The calculated dormancy requirements, mean temperatures of the four decades of the year, and January and February average NAO index recorded during the period belbre flowering, were used to construct linear and multiple regression models in order to forecast the start date of the alder pollen seasons Its accuracy was tested using data from 2007, and the difference between the predicted and observed dates ranged from 3-7 days. [ABSTRACT FROM AUTHOR]

Artemisia pollen grains are important aeroallergens worldwide. The amount of allergenic proteins produced by pollen, or pollen allergenicity, is regulated by both genes and the environment. As a result, even closely related plant taxa may release pollen with distinctly different allergen contents. Here, we determined the variability in atmospheric exposure to the major Artemisia pollen allergen, Art v 1, during the pollination seasons of two common species, i.e., A. vulgaris (early flowering species) and A. campestris (late flowering species), in Poznań, Poland (2013–2015). Artemisia pollen grains were collected using Hirst-type volumetric trap, while Art v 1 was collected by a two-stage cascade impactor (PM 10 and PM >10 air fractions) and quantified by immunoenzymatic analysis. The results showed that daily Art v 1 levels correlated significantly with mean daily concentrations of Artemisia pollen (from r = 0.426 to r = 0.949, depending on air fraction and peak of the season). Significant differences were observed between 1) the median pollen allergenicity in different seasons (from 2.5 to 4.7 pg Art v 1/pollen) and 2) the median pollen allergenicity in different peak periods of the season (from 1.8 to 6.7 pg Art v 1/pollen). During the late peak (flowering of A. campestris), the median pollen allergenicity was significantly higher (on average by 63%, p < 0.05) than that during A. vulgaris flowering. The highest mean seasonal pollen allergenicity was observed during the wettest season, while the lowest was observed during the driest season (from July–August). In summary, our study showed distinct differences in Artemisia pollen allergenicity, that were not only related to daily and seasonal variability, which may exceed 800% and 80%, respectively but also noticeable when two common Artemisia species were compared. Therefore, we argue that variability in pollen allergenicity (both seasonal and species-specific) should be considered in future studies assessing pollen exposure. Unlabelled Image • Art v 1 in the PM >10 air fraction accounted for 86% of the total Art v 1 level. • The daily Art v 1 and Artemisia pollen concentration were significantly correlated. • Seasonal Artemisia pollen allergenicity varied from 2.5 to 4.7 pg Art v 1/pollen. • High seasonal pollen allergenicity was observed during the wet and warm seasons. • Pollen allergenicity increased by 63% during the A. campestris flowering period. [ABSTRACT FROM AUTHOR]

Birch trees are abundant in central and northern Europe and are dominant trees in broadleaved forests. Birches are pioneer trees that produce large quantities of allergenic pollen efficiently dispersed by wind. The pollen load level depends on the sizes and locations of pollen sources, which are important for pollen forecasting models; however, very limited work has been done on this topic in comparison to research on anthropogenic air pollutants. Therefore, we used highly accurate aerial laser scanning (Light Detection and Ranging—LiDAR) data to estimate the size and location of birch pollen sources in 3-dimensional space and to determine their influence on the pollen concentration in Poznań, Poland. LiDAR data were acquired in May 2012. LiDAR point clouds were clipped to birch individuals (mapped in 2012–2014 and in 2019), normalised, filtered, and individual tree crowns higher than 5 m were delineated. Then, the crown surface and volume were calculated and aggregated according to wind direction up to 2 km from the pollen trap. Consistent with LIDAR data, hourly airborne pollen measurements (performed using a Hirst-type, 7-day volumetric trap), wind speed and direction data were obtained in April 2012. We delineated 18,740 birch trees, with an average density of 14.9/0.01 km2, in the study area. The total birch crown surface in the 500–1500 m buffer from the pollen trap was significantly correlated with the pollen concentration aggregated by the wind direction (r = 0.728, p = 0.04). The individual tree crown delineation performed well (r2 ≥ 0.89), but overestimations were observed at high birch densities (> 30 trees/plot). We showed that trees outside forests substantially contribute to the total pollen pool. We suggest that including the vertical dimension and the trees outside the forest in pollen source maps have the potential to improve the quality of pollen forecasting models. [ABSTRACT FROM AUTHOR]

Large-scale synoptic conditions are able to transport considerable amounts of airborne particles over entire continents by creating substantial air mass movement. This phenomenon is observed in Europe in relation to highly allergenic ragweed (Ambrosia L.) pollen grains that are transported from populations in Central Europe (mainly the Pannonian Plain and Balkans) to the North. The path taken by atmospheric ragweed pollen often passes through the highly industrialised mining region of Silesia in Southern Poland, considered to be one of the most polluted areas in the EU. It is hypothesized that chemical air pollutants released over Silesia could become mixed with biological material and be transported to less polluted regions further North. We analysed levels of air pollution during episodes of long-distance transport (LDT) of ragweed pollen to Poland. Results show that, concomitantly with pollen, the concentration of air pollutants with potential health-risk, i.e. SO 2 , and PM 10 , have also significantly increased (by 104% and 37%, respectively) in the receptor area (Western Poland). Chemical transport modelling (EMEP) and air mass back-trajectory analysis (HYSPLIT) showed that potential sources of PM 10 include Silesia, as well as mineral dust from the Ukrainian steppe and the Sahara Desert. In addition, atmospheric concentrations of other allergenic biological particles, i.e. Alternaria Nees ex Fr. spores, also increased markedly (by 115%) during LDT episodes. We suggest that the LDT episodes of ragweed pollen over Europe are not a "one-component" phenomenon, but are often related to elevated levels of chemical air pollutants and other biotic and abiotic components (fungal spores and desert dust). Image 1 • Long-distance transport (LDT) of ragweed pollen is a common phenomena in Europe. • LDT episodes are associated to increased levels of SO 2 , PM 10 and Alternaria spores. • Alternaria spores are released concomitantly with pollen from agricultural sources. • SO 2 /PM 10 mixes with the plume of pollen over industrialised regions of Southern Poland. • Mineral dust originated from the Sahara is also present during LDT episodes. [ABSTRACT FROM AUTHOR]

Airborne pollen might be transported over thousands of kilometres, which has important ecological, evolutionary and clinical consequences. The long-distance transport (LDT) of birch (Betula sp.) pollen has been described in detail for northern Europe. However, a comprehensive analysis of this transport from other European regions is lacking. This study focused on the post-seasonal LDT of birch pollen to Poland (central Europe), with special attention paid to determining potential source areas of pollen and describing the causal mechanism favouring LDT episodes. Pollen monitoring (1997–2016) was conducted in Poznań and Rzeszów (500 km away from each other) using volumetric traps. The LDT episodes were characterized by analysing the (1) bi-hourly backward air mass trajectories using the Hybrid Single Particle Lagrangian Integrated Trajectory model (HYSPLIT); (2) sea level pressure (SLP) and 500 hPa geopotential height (z500) anomalies; and (3) patterns of the Enhanced Vegetation Index to determine the birch flowering time along the moving air mass trajectories. The potential locations of birch populations within broadleaved forests were estimated with GLOBCOVER data. Finally, the movement of pollen emitted from potential source areas was simulated using the HYSPLIT dispersion model. LDT episodes were mainly recorded in the first fortnight of May. The main source areas of pollen to Poland were western Russia, Belarus and to a lesser extent the eastern Baltic republics and the Scandinavian Peninsula. In most cases, a high-pressure centre located over Scandinavia and an elevated z500 over Germany-Denmark-Sweden favoured pollen transport. On average, the post-seasonal LDT episodes of birch pollen to Poland occur almost every year (Poznań) or every second year (Rzeszów). The episodes are highly variable in time; thus, the pollen concentration may unexpectedly cause allergy symptoms in sensitized patients. In some cases, these episodes may be extremely severe, thereby prolonging and strengthening the exposure to birch pollen allergens. Unlabelled Image • Airborne birch pollen transport from distant sources occurred almost every year. • Long-distant transport (LDT) episodes occurred mainly in the first fortnight of May. • A high pressure centre over Scandinavia favoured the LDT of birch pollen to Poland. • Potential pollen source areas were located primarily in western Russia. • LDT caused a clinically relevant extension of the birch pollen season in Poland. [ABSTRACT FROM AUTHOR]

• Quantification of starch in ambient air by laser spectroscopy bioaerosol monitoring. • Insights into atmospheric processes via high temporal resolution data. • Identification of sources of airborne particles. • Notable amounts of airborne starch are related to cereal grain storage facilities. Considerable amounts of starch granules can be present in the atmosphere from both natural and anthropogenic sources. The aim of this study is to investigate the variability and potential origin of starch granules in ambient air recorded at six cities situated in a region with dominantly agricultural land use. This is achieved by using a combination of laser spectroscopy bioaerosol measurements with 1 min temporal resolution, traditional volumetric Hirst type bioaerosol sampling and atmospheric modelling. The analysis of wind roses identified potential sources of airborne starch (i.e., cereal grain storage facilities) in the vicinity of all aerobiological stations analysed in this study. The analysis of the CALPUFF dispersion model confirmed that emission of dust from the location of storage towers situated about 2.5 km north of the aerobiological station in Novi Sad is a plausible source of high airborne concentrations of starch granules. This study is important for environmental health since it contributes body of knowledge about sources, emission, and dispersion of airborne starch, known to be involved in phenomena such as thunderstorm-triggered asthma. The presented approach integrates monitoring and modelling, and provides a roadmap for examining a variety of bioaerosols previously considered to be outside the scope of traditional aerobiological measurements. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Exposure to allergens is pivotal in determining sensitization and allergic symptoms in individuals. Pollen grain counts in ambient air have traditionally been assessed to estimate airborne allergen exposure. However, the exact allergen content of ambient air is unknown. We therefore monitored atmospheric concentrations of birch pollen grains and the matched major birch pollen allergen Bet v 1 simultaneously across Europe within the EU-funded project HIALINE (Health Impacts of Airborne Allergen Information Network). Pollen count was assessed with Hirst type pollen traps at 10 l min−1 at sites in France, United Kingdom, Germany, Italy and Finland. Allergen concentrations in ambient air were sampled at 800 l min−1 with a Chemvol® high-volume cascade impactor equipped with stages PM > 10 μm, 10 μm > PM > 2.5 μm, and in Germany also 2.5 μm > PM > 0.12 μm. The major birch pollen allergen Bet v 1 was determined with an allergen specific ELISA. Bet v 1 isoform patterns were analyzed by 2D-SDS-PAGE blots and mass spectrometric identification. Basophil activation was tested in an FcɛR1-humanized rat basophil cell line passively sensitized with serum of a birch pollen symptomatic patient. Compared to 10 previous years, 2009 was a representative birch pollen season for all stations. About 90% of the allergen was found in the PM > 10 μm fraction at all stations. Bet v 1 isoforms pattern did not vary substantially neither during ripening of pollen nor between different geographical locations. The average European allergen release from birch pollen was 3.2 pg Bet v 1/pollen and did not vary much between the European countries. However, in all countries a >10-fold difference in daily allergen release per pollen was measured which could be explained by long-range transport of pollen with a deviating allergen release. Basophil activation by ambient air extracts correlated better with airborne allergen than with pollen concentration. Although Bet v 1 is a mixture of different isoforms, its fingerprint is constant across Europe. Bet v 1 was also exclusively linked to pollen. Pollen from different days varied >10-fold in allergen release. Thus exposure to allergen is inaccurately monitored by only monitoring birch pollen grains. Indeed, a humanized basophil activation test correlated much better with allergen concentrations in ambient air than with pollen count. Monitoring the allergens themselves together with pollen in ambient air might be an improvement in allergen exposure assessment. [Copyright &y& Elsevier]

High Ambrosia pollen concentrations in Poland rather rarely come from the local sources. The aim of this study was to define the temporal and spatial differences of the high Ambrosia pollen concentrations by creating models for the pollen transport from the distant sources. This study was thought to determine the direction of the air masses inflow into Poland, carrying Ambrosia pollen, from areas of the bordering countries with the pollen concentrations higher than iSTOTEN_n Poland. Pollen and meteorological datasets at 8 monitoring sites in Poland, and daily pollen concentrations at 11 sites in the Czech Republic, 5 sites in Slovakia and 3 sites in Ukraine were analysed recently. Days with concentrations ≥10 Pollen/m3 and concurrent meteorological situations were analysed in great deal. The HYSPLIT model was applied to compute backward trajectories up to 4 days backward (96 h) and at three altitudes: 20, 500 and 1000 m above ground level (a.g.l.). High pollen concentrations occur most frequently when the air masses inflow into Poland from southerly (S, SE, SW, 44%) and easterly (E, 6%) directions and in no advection situations (25%). In years with the highest frequency of days over 10 Pollen/m3, the prevailing directions of the pollen influx into Poland were from the South (2004–2006, 2008, 2011) but in one year (2014) from the East. Trajectories for the studied period show that air masses come most frequently from Slovakia and the Czech Republic. Sometimes, the Ambrosia pollen transport happens from Ukraine. Unlabelled Image • Ambrosia pollen influx into Poland was studied. • Back trajectory analyses were performed for selected sites. • High Ambrosia pollen concentrations were associated with direction of air masses. • The most frequent pollen influx was observed from prevailing southerly direction. • In 2014 the pollen transport from the easterly direction dominated. [ABSTRACT FROM AUTHOR]

Background: Ambrosia artemisiifolia L. is a noxious invasive alien species in Europe. It is an important aeroallergen and millions of people are exposed to its pollen., Objective: The main aim of this study is to show that atmospheric concentrations of Ambrosia pollen recorded in Denmark can be derived from local or more distant sources., Methods: This was achieved by using a combination of pollen measurements, air mass trajectory calculations using the HYPLIT model and mapping all known Ambrosia locations in Denmark and relating them to land cover types., Results: The annual pollen index recorded in Copenhagen during a 15-year period varied from a few pollen grains to more than 100. Since 2005, small quantities of Ambrosia pollen has been observed in the air every year. We have demonstrated, through a combination of Lagrangian back-trajectory calculations and atmospheric pollen measurements, that pollen arrived in Denmark via long-distance transport from centres of Ambrosia infection, such as the Pannonian Plain and Ukraine. Combining observations with results from a local scale dispersion model show that it is possible that Ambrosia pollen could be derived from local sources identified within Denmark., Conclusions: The high allergenic capacity of Ambrosia pollen means that only small amounts of pollen are relevant for allergy sufferers, and just a few plants will be sufficient to produce enough pollen to affect pollen allergy sufferers within a short distance from the source. It is necessary to adopt control measures to restrict Ambrosia numbers. Recommendations for the removal of all Ambrosia plants can effectively reduce the amount of local pollen, as long as the population of Ambrosia plants is small.