The variability of pollen concentrations at two stations in the city of Wrocław in Poland In the original publication of the article, the SPIn values in Tables 1 and 4 were incorrectly published. The correct Tables 1 and 4 are given below.

Rapid pollen rupture and release of pollen cytoplasmic granules upon hydration of allergenic grass and weed species commonly found in subtropical regions Abstract Airborne pollen is an important and potent source of allergens. Allergenic protein components located in the cytoplasm of pollen, so-called pollen cytoplasmic granules, are released upon contact with moisture, thereby inducing allergic symptoms. However, few studies have compared factors affecting pollen rupture and protein release from allergenic pollen. This study investigated the dynamics of pollen rupture and protein release upon hydration using common allergenic grass and weed species in subtropical regions. The three factors examined were incubation time, incubating solution, and pollen age after shedding. We found that pollen rupture and protein release occurred rapidly upon contact with solutions. The highest amount of protein was released within 15 min after incubation. As expected, pollen rupture increased as incubation time increased. Fresh pollen had higher rupture percentage and released a higher amount of protein than aged pollen. Rainwater caused more rupture and triggered more protein release than other tested solutions. The dynamics of rupture and the amount of released protein were drastically different among species. In conclusion, incubation time, incubating solution, and age of pollen significantly affected the amount of pollen rupture and protein release from allergenic pollen. This information provided better understanding of factors involving the release of allergenic protein from pollen in relation to its internal and external conditions, which could affect its allergenicity.

Ultraviolet light measurements (280–400 nm) acquired from stratospheric balloon flight to assess influence on bioaerosols Abstract Viable microorganisms collected from the Earth’s upper atmosphere are mysterious considering the intensely biocidal ultraviolet (UV) light conditions dominating rarefied air. Historically, most investigations examining the relationship between bioaerosols and UV conditions in the upper atmosphere have relied upon model-generated data. To address the shortage of in situ UV measurements in the upper troposphere and lower/middle stratosphere, we flew a meteorological balloon equipped with a UV radiometer and other core environmental sensors. The balloon payload launched from Illinois, USA, on October 6, 2018, and acquired UVA (315–400 nm) + UVB (280–315 nm) measurements for ~ 2 h up to 30.9 km. Above the atmospheric boundary layer, UVA + UVB values registered around 6 mW cm−2, results that were largely consistent with Tropospheric Ultraviolet–Visible model predictions. Performed in a low-cost, reusable manner with commercially available instruments, we show that reliable UV flux data can be acquired with meteorological balloon payload systems. This short communication provides relevant UVA + UVB results for aerobiology and astrobiology studies evaluating the survivability of microorganisms in the upper atmosphere.

Effect of the Mediterranean crops in the airborne pollen spectrum Abstract The impact of pollen grains as an allergenic factor is an important object of study. Various statistical analyses have been used to describe the behaviour of anemophilous plants, including certain Mediterranean cultivars (Olea europaea, Vitis vinifera, etc.). The main aims of this study are to define the pollen spectrum within an agricultural area and the effects of meteorological parameters and to examine whether Spearman’s correlation and ReDundancy Analysis (RDA) provide similar information. Aerobiological sampling was conducted using a Hirst-type volumetric spore trap from January 2015 to August 2018 in the Montilla mountains, in the south of the province of Córdoba, in an agricultural area close to a small city. In this location, the effect of ornamental plants is reduced and the cultivar effect becomes more important. Taking into account the average percentage for all years, the most abundant pollen types were Olea, Quercus, Poaceae, Urticaceae, Urtica membranacea, Vitis, Plantago, Pinus and Amaranthaceae. Due to the climatic characteristics of the study area, the meteorological parameters with most influence were temperature and dew point. The pollen spectrum in the study zone is caused by the agricultural use of the land, increasing the concentrations of some allergenic pollen types and decreasing the diversity of airborne pollen types. The RDA analysis gives a better explanation of the complex relationship between meteorological parameters and airborne pollen release and dispersion compared with the Spearman’s correlation.

Relationship between airborne pollen and skin prick test results in Elazığ, Turkey Abstract This study investigated the relationship between the types of pollen in the air and sensitization to pollen in a skin prick test in allergic children. The pollen in the atmosphere of Elazığ city was measured between June 2013 and June 2014. The study included 520 children with allergic complaints. In the atmosphere of Elazığ city, pollen belonging to a total of 38 taxa was identified, including 20 woody plants and 18 herbaceous plants. The annual pollen integral of 108,313 pollen day/m3 from the 38 taxa was identified. The most common pollen detected was woody plants (76.4%), weeds (14.1%), Poaceae (Gramineae) (9.1%), and unidentified plants (0.4%). The skin prick test in allergic children found that they were most commonly sensitized to mixture of grasses and cereals (43.8%), weed (14.1%), tree mixture I (10.1%), and tree mixture II (7.9%). There was no direct relationship between the frequency of pollen types in the atmosphere and the sensitization frequency to pollen, as identified by the skin prick test in allergic patients. We believe that the data from this study will provide new information to other researchers and clinicians in the evaluation of allergic diseases.

Enabling self-management of pollen allergies: a pre-season questionnaire evaluating the perceived benefit of providing local pollen information Abstract The Australian AusPollen Partnership provides respiratory allergy patients with accurate, relevant and localised pollen information via smartphone Apps. This study aims to evaluate public perceptions of need and benefit of providing local pollen information. Individuals aged 18 years and older were contacted through AusPollen Smartphone Apps (Brisbane, Sydney, Canberra and Melbourne), Australian Society for Clinical Immunology and Allergy, Asthma Australia and social media. A pilot questionnaire was developed in consultation with partner organisations, including select questions drawn from the National Young People and Asthma Survey. The questionnaire consisted of four sections: participant demographics, allergic rhinitis and asthma symptoms, symptom management and App utility. One hundred and twenty-seven people completed the survey, of whom 53% had access to local pollen information. Most (97%) participants without access to local pollen information indicated that they wanted such a service. Pollen information was most commonly perceived by participants to be useful for prevention and avoidance as well as preparation and planning. This preliminary study identified a public demand for local pollen information. Users identified practical ways in which pollen information assisted them. Publicised pollen concentrations and forecasts have the potential to improve awareness of allergy triggers and empower patient self-management, reducing symptoms and burden of disease.

Spatio-temporal monitoring and modelling of birch pollen levels in Belgium Abstract In Belgium, ~ 10% of the people is estimated to suffer from allergies due to pollen emitted by the birch family trees. Timely information on forthcoming pollen exposure episodes using a forecasting system can allow patients to take preventive measures. To date, the only available information on pollen concentrations in Belgium comes from five stations that monitor daily airborne birch pollen concentrations, but real-time and detailed spatial information is lacking. Pollen transport models can both quantify and forecast the spatial and temporal distribution of airborne birch pollen concentrations if accurate and updated maps of birch pollen emission sources are available and if the large inter-seasonal variability of birch pollen is considered. Here we show that the SILAM model driven by ECMWF ERA5 meteorological data is able to determine airborne birch pollen levels using updated maps of areal fractions of birch trees, as compared to the pollen observations of the monitoring stations in Belgium. Forest inventory data of the Flemish and Walloon regions were used to update the default MACCIII birch map. Spaceborne MODIS vegetation activity combined with an updated birch fraction map and updated start and end dates of the birch pollen season were integrated into SILAM. The correlation (R2) between SILAM modelled and observed time series of daily birch pollen levels of 50 birch pollen seasons increased up to ~ 50%. The slopes of the linear correlation increased on average with ~ 60%. Finally, SILAM is able to capture the threshold of 80 pollen grains m−3 exposure from the observations.

Concentration and size distribution of microbial aerosol in the historical objects in Kraków as a potential health risk and biodeterioration factor Abstract Historical facilities such as churches, crypts, libraries and museums are crucial for preserving cultural heritage but at the same time, they are frequently visited tourist objects and working environment. The aim of this study was to assess whether there are differences in the concentration and size distribution of bacterial and fungal aerosol in the mentioned groups of historical objects in Kraków, as well as to determine if there is tendency for seasonal fluctuations of bioaerosol concentrations, and what environmental parameters affect them most significantly. The concentrations of bacterial and fungal aerosol were measured in ten historical objects—churches, crypts, libraries and museums—using a six-stage Andersen impactor. Microbiological analyses were accompanied by measurements of particulate matter (PM10, PM4, PM2.5 and PM1) and microclimatic parameters. The results showed that the studied objects differ in terms of bioaerosol levels, but the differences were not drastic and in terms of bacterial aerosol concentrations the objects can be arranged as follows: churches > libraries > museums > crypts, while for fungal aerosol the order would be: churches > museums > crypts > libraries. The concentrations of bioaerosol did not exceed the safety levels for human exposure, but the levels suggesting possible threat of biodeterioration and the presence of internal source of contamination were exceeded in nearly all sites. The share of respirable fraction of bioaerosol was high (42.1–90.5% for bacteria and 80.7–94.7% for fungi). Bioaerosol concentration was most significantly associated with indoor temperature, and the impact of particulate matter was only moderate.

Study of the immunological changes associated with Aspergillus infection among ceramic workers Abstract Ceramic workers are exposed to high levels of respirable dust that contains high microbial levels such as Aspergillus. It is recommended to consider fungal exposure in ceramic industry as a hazardous problem. This work aimed to study the impact of occupational exposure to high environmental concentrations of Aspergillus on the immune parameters related to the respiratory system in ceramic workers. Serum levels of total IgE, intercellular adhesion molecule-1 (ICAM-1), alpha 1-antitrypsin (α1AT), and tumor necrosis factor alpha (TNF-α) were assessed in 40 ceramic workers and 56 matched controls. Statistical analysis revealed that the levels of total IgE and ICAM-1 were higher in both non-smoker and smoker ceramic workers compared to their controls. While TNF-α was significantly lower in non-smoker ceramic workers compared to non-smoker controls. In addition, ceramic workers with sputum negative PCR for Aspergillus had lower TNF-α than those with positive PCR. α1AT levels did not differ significantly among the examined groups. These changes were not correlated to the duration of exposure. In conclusion, occupational exposure to Aspergillus may cause different effects on immunological parameters related to respiratory problems in ceramic workers.

Pollen season identification for three pollen taxa in Thessaloniki, Greece: a 30-year retrospective analysis Abstract To examine the applicability of the recently proposed criteria by the European Academy of Allergy and Clinical Immunology (EAACI) for pollen season (PS) definition, we applied them to a 30-year time series of daily concentrations of cypress (Cupressaceae), olive (Oleaceae), and grass (Poaceae) airborne pollen from a Mediterranean city, Thessaloniki, Greece. These criteria led to PS definition for every year in the case of grasses, but they did not result to a defined pollen season in each year for 10% of the examined period in the case of cypress (Cupressaceae) and even for 60% in the case of olive (Oleaceae). Application of the EAACI thresholds to data series of Thessaloniki shows the need for an accurate analysis and revision of the symptom thresholds for PS definition for olive and cypress in the Mediterranean area. Given that the PS, as defined after the EAACI criteria, corresponds to only the part of the PS inducing allergy symptoms, a different term ‘allergy symptom-inducing pollen season’ is proposed so as to avoid confusion but also make clear that, depending on the purpose of the study, different criteria may be used for PS definition.