This study aimed to investigate the distribution characteristics, sensitization patterns and potential correlation of airborne pollen allergens of physician-diagnosed pollen-induced allergic rhinitis (PiAR) patients in Ordos city in grasslands region. This retrospective study enrolled 234 patients with confirmed PiAR. Skin prick tests (SPT) of 12 common pollen allergens were used to detect and analyze the correlation of pollen allergens. Kendall's tau-b correlation was performed. The LASSO regression model was used to select the most important variables. Multi-adjusted logistic regression was performed to predict the risk of Artemisia sensitization. Artemisia, sunflower and lambsquarters were the top three sensitizing pollen allergens, and the highest sensitization rate was for Artemisia (72.22%). The sensitization rate of weed-pollen was higher than that of tree-pollen. Kendall's tau-b correlation results showed a moderate (0.4< r<0.6) to strong (0.6<r< 0.8) correlation between tree and grass pollen allergens. Age sex adjusted logistic regression showed tree (birch, green ash) and weed (Japanese hop, lambsquarters, sunflower) and grass (corn) pollen allergic was risk factors for artemisia sensitization while age was a protective factor (all P＜0.05). Multivariate logistic regression showed that sunflower (OR=28.34[95%CI:6.166-130.263], P＜0.0001) and lambsquarters (OR=3.596[95%CI:1.06-12.204], P=0.0401) were risk factors for artemisia sensitization, especially in female PiAR. The positive correlation of SPT results indicated the co‑sensitization among common pollen allergens. Sunflower was the most significant independent risk factor for artemisia sensitization, and co-sensitization with lambsquarters would greatly increase the risk of sensitization to artemisia.

Airborne pollen has emerged as a critical environmental driver of allergic respiratory diseases, particularly under the accelerating influence of global climate change. This study investigates the short-term effects of daily airborne pollen concentrations on the incidence of allergic rhinitis (AR) and bronchial asthma (BA) in Lanzhou, a representative arid city in northwestern China. Utilizing outpatient visit data from a Class A tertiary hospital between April and October 2024, along with daily records of pollen concentrations, meteorological indicators, and air pollutant levels, we employed a Distributed Lag Non-linear Model (DLNM) to examine the non-linear and lagged relationships between pollen exposure and disease risk. Our findings reveal a significant association between elevated pollen levels and increased risks of both AR and BA, with the strongest effects observed within 1-3 days after exposure. Stratified analyses show that females and individuals aged 0-19 years are particularly susceptible. Moreover, health impacts were more pronounced during the late summer to autumn pollen season, likely due to the presence of highly allergenic species such as Artemisia and Chenopodiaceae. Thunderstorm events were also found to coincide with spikes in pollen concentrations and disease incidence, suggesting a potential link to thunderstorm-related allergic exacerbations. These results underscore the urgent need for region-specific pollen monitoring systems, early warning mechanisms, and targeted public health interventions to mitigate the burden of allergic respiratory diseases in vulnerable populations, particularly under increasingly volatile climatic conditions.

Introduction: In recent years, coastal cities like Dalian have experienced a notable rise in pollen-induced allergic rhinitis (PiAR). This trend highlights the urgent need to investigate how climatic changes and air pollution exacerbate this growing public health challenge. This study examines the combined effects of meteorological variables, air pollutants, and airborne pollen on weed PiAR symptoms in Dalian, a coastal city located in the warm temperate zone of China. Methods: Daily pollen concentrations were monitored from August to October 2023, concurrently with meteorological data and air quality indices. Clinical data, including symptoms and fractional exhaled nitric oxide (FENO) levels, were collected from 61 PiAR patients to evaluate the impact of environmental factors on allergy severity and airway inflammation. Results: Among meteorological variables, temperature exhibited a positive influence on the concentrations of total pollen, specifically that of Artemisia, Humulus, and Chenopodium pollen, while air pressure showed an inverse relationship. Regarding air pollutants, O3 concentration was positively associated with Artemisia pollen levels, whereas CO and NO2 were negatively associated. Statistical analysis demonstrated a strong positive correlation between daily weed pollen concentrations and the Combined Symptom and Medication Score (CSMS) (r = 0.81, p < 0.0001), as well as between weekly average pollen concentrations and the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) score (r = 0.95, p < 0.0001). Pollen exposure showed a significant immediate effect on CSMS at lag 0 (EE = 0.205, 95% CI: 0.076–0.334), while air pressure exhibited significant lagged and cumulative effects during lag days 0–5 (EE = 0.815, 95% CI: 0.337–1.293). Notably, the interaction between temperature and air pressure was also statistically significant (p < 0.001). Additionally, FENO levels in PiAR patients significantly rose during the peak weed pollen season (p < 0.001), indicating elevated airway inflammation. Conclusion: This study highlights the complex interplay between meteorological factors, air pollutants, and pollen in exacerbating allergic symptoms. The findings underscore the need for integrated environmental and clinical management strategies to mitigate the burden of PiAR in urban settings.

Abstract Ambrosia artemisiifolia L. (common ragweed) is an invasive species in Europe that produces highly allergenic pollen with substantial health impacts. Recently, populations showing aberrant floral morphotypes, characterised by bracteate racemes and strongly reduced or absent staminate heads, have been observed, particularly at field margins. The causes of these abnormalities remain unclear, although the involvement of pathogens has been suggested. We hypothesised that aberrant populations differ from typical ones in both the amount of airborne pollen released and the spectrum of other bioparticles, including potential phytopathogens. To test this, spore traps were installed at three heights (0, 50, and 150 cm) above both typical and aberrant populations, and the captured airborne bioparticles were analysed. Pollen concentrations were markedly reduced above aberrant populations, consistent with their feminised floral structures. Differences were also observed in the composition and abundance of airborne fungal spores, with several phytopathogenic taxa, such as Cryptophyllachora, Albugo, and Puccinia, occurring more frequently above aberrant stands. These findings provide the first aerobiological evidence of distinct airborne particle profiles associated with the aberrant morphotype, highlighting possible links with phytopathogens. Further work, including tissue-level pathogen detection, will be required to confirm causal relationships.

Rotapollen Sampler: An affordable, portable, and programmable rotorod-style device for measuring airborne pollen concentrations

Natural disasters (including heatwaves, wildfires, hurricanes, floods, earthquakes and volcanic eruptions) significantly impact respiratory health, posing heightened risks to vulnerable populations such as individuals with pre-existing conditions, children, and the elderly. This review explores the complex relationship between natural catastrophes and respiratory health, emphasising the roles of chemical pollutants, biocontaminants and meteorological factors. Epidemiological evidence highlights alarming trends, including increased asthma exacerbations, COPD hospitalisations and respiratory infections following these events. During heatwaves, elevated ozone levels and emissions from power generation for air conditioning exacerbate respiratory conditions, while fine and ultrafine particulate matter, particularly during dust storms and wildfires, emerge as a major contributor to respiratory morbidity and mortality. Volcanic eruptions release hazardous gases, corrosive minerals and plumes of particles and dust into the atmosphere, which exacerbate symptoms in individuals with pre-existing respiratory conditions. Thunderstorms often increase airborne pollen and mould concentrations, triggering episodes of thunderstorm asthma. Earthquake-damaged buildings are significant sources of dust, worsening respiratory symptoms among affected populations. Floods are the origin of mould proliferation, responsible for asthma and other respiratory diseases. First responders, such as firefighters, face acute and potentially chronic respiratory issues due to prolonged exposure to chemical pollutants and biocontaminants during rescue operations. Marginalised communities disproportionately bear the brunt of these health impacts due to systemic vulnerabilities and limited adaptive capacities. This review underscores the escalating respiratory health threats posed by natural disasters amid ongoing climate change. An integrated approach is needed to address these challenges through improved understanding, targeted interventions, and proactive measures to mitigate risks.

The commercial realization of hybrid wheat (Triticum aestivum L.) is a major technological challenge to sustainably increase food production for our growing population in a changing climate. Despite recent advances in cytoplasmic- and nuclear-based pollination control systems, the inefficient outcrossing of wheat's autogamous florets remains a barrier to hybrid seed production. There is a pressing need to investigate wheat floral biology and enhance the likelihood of ovaries being fertilized by airborne pollen so breeders can select and utilize male and female parents for resilient, scalable, and cost-effective hybrid seed production. Advances in understanding the wheat genomes and pangenome will aid research into the underlying floral organ development and fertility with the aim to stabilize pollination and fertilization under a changing climate. The purpose of this position paper is to highlight priority areas of research to support hybrid wheat development, including (1) structural aspects of florets that affect stigma presentation, longevity, and receptivity to airborne pollen, (2) pollen release dynamics (e.g., anther extrusion and dehiscence), and (3) the effect of heat, drought, irradiation, and humidity on these reproductive traits. A combined approach of increased understanding built on the genomic resources and advanced trait evaluation will deliver to robust measures for key floral characteristics, such that diverse germplasm can be fully exploited to realize the yield improvements and yield stability offered by hybrids.

A 15-year survey of pollen aeroallergens in North Texas.

This study investigated airborne pollen concentrations in the Posof District of Ardahan Province during 2020 and 2021. The significance of the study lies in the region’s location on the Georgian border and its transitional position between the Eastern Anatolia and Black Sea regions, which influence its vegetation and pollen composition. Pollen sampling was conducted using Hirst-type volumetric 7-day pollen and spore trap, identifying 39 taxa-21 woody and 18 herbaceous. The dominant pollen taxa were Pinaceae (37.18%), Betula (14.55%), Poaceae (9.35%), Cupressaceae/Taxaceae (7.26%), and Urticaceae (7.04%). The highest pollen concentrations were recorded in May, indicating a seasonal peak. Taxonomic pollen diversity in Posof showed similarities to both Black Sea and Eastern Anatolian regions. Spearman’s correlation analysis revealed a positive correlation between mean daily temperature and wind speed with pollen concentrations, whereas relative humidity showed a negative correlation. Due to the region’s geographical and climatic conditions, the onset dates of identified pollen types were delayed by 2–4 weeks compared to similar studies. This delay is attributed to altitude and specific meteorological conditions, particularly lower spring temperatures, persistent snow cover, and delayed warming, which collectively postpone plant phenology and pollen release. The findings contribute to understanding airborne pollen dynamics in Posof and provide valuable data for regional aerobiological studies.

This study investigates the composition, abundance, and seasonal variability of airborne pollen in Siirt, a transitional region between the Irano-Turanian and Mediterranean phytogeographical zones in southeastern Türkiye. The main objective was to assess pollen diversity and its relationship with meteorological parameters over a two-year period (2022-2023). Airborne pollen was collected using a Hirst-type volumetric pollen and spore trap; a total of 18,666 pollen grains/m3 belonging to 37 taxa were identified. Of these, 70.67% originated from woody taxa and 29.33% from herbaceous taxa. Peak concentrations occurred in April, with the lowest levels in December. The dominant taxa, all exceeding 1% of the total, were Pinaceae (31.00%); Cupressaceae/Taxaceae (27.79%); Poaceae (18.42%); Moraceae (4.23%); Amaranthaceae (2.42%); Urticaceae (2.13%); Quercus (1.55%); Fabaceae (1.29%); and Rumex (1.02%). Spearman's correlation analysis revealed significant relationships between daily pollen concentrations and meteorological variables such as temperature, humidity, precipitation, and wind speed. These findings highlight that both climatic conditions and the surrounding vegetation, shaped by regional land cover, play a crucial role in determining pollen dynamics. In conclusion, this study provides the first aerobiological baseline for Siirt and contributes valuable data for allergy-risk forecasting and long-term ecological monitoring in southeastern Türkiye.

Lanzhou, an industrial city in northwestern China, is prone to air pollution due to its unique valley basin topography. The incidence of otolaryngologic diseases is closely related to the air quality. Based on air-quality data and outpatient data from an otolaryngology clinic within a hospital in Lanzhou during 2014‒2022, we analyzed the statistical relationships between the concentrations of six common air pollutants and the number of outpatient visits for common otolaryngologic inflammatory diseases using a generalized additive model. We used the results to discuss the potential role of urban airborne pollen in contributing to allergic rhinitis, and we also examined the variability of the relationship between air pollutants and otolaryngologic diseases under anthropogenic interventions using periods before and during the COVID-19 outbreak. Rising concentrations of CO, NO2, PM2.5, PM10, and SO2 in Lanzhou led to an increase in the number of outpatient visits for otolaryngologic inflammatory diseases, and the impact patterns were different for different genders and different diseases. In terms of gender, CO, NO2, and SO2 had a significantly greater impact on the number of visits for otolaryngologic inflammatory disease for males than for females, while PM2.5 and PM10 had a more significant impact on the female population. The number of outpatient visits for acute otitis media and allergic rhinitis also increased with increasing concentrations of the above five pollutants, while airborne pollen was an important trigger for high incidences of allergic rhinitis in July and August. In addition, during the period of lockdown and control due to the COVID-19 pandemic, there was a decrease in the relative risk of the five aforementioned pollutants with respect to the occurrence of inflammatory otolaryngologic disorders. The effect of these pollutants on such disorders was reduced compared with that observed during the pre-pandemic period, indicating that effective air pollution control is an important measure that can be implemented to reduce the occurrence of otolaryngologic inflammatory diseases and protect residents. This study reveals the occurrence pattern of otolaryngologic diseases and their relationships with air pollutants in Lanzhou, which is important for the prevention of otolaryngologic diseases and the formulation of air pollution control strategies.

BackgroundChildhood asthma is a prevalent chronic respiratory disease globally. Airborne pollen is a known environmental trigger, but the impact of different pollen types on pediatric asthma remains unclear. Seasonal and geographic pollen variations, influenced by climate change, may affect asthma patterns. A comprehensive review is needed to clarify these associations and guide prevention strategies.MethodsRelevant literature on the association between airborne pollen and asthma in children was retrieved from CNKI, Wanfang Data, VIP, CBM, Web of Science, PubMed, Cochrane and Embase at home and abroad from the establishment of the database to March 1, 2025. EndNote X8 and Excel 2021 were used for data management and screening, while Stata 15 was used for statistical analysis.ResultsA total of 9 articles were included in this meta-analysis, from 2007 to 2024, with a total sample size of 87,270 children. The pooled analysis showed that airborne pollen exposure was significantly associated with the risk of childhood asthma (OR = 1.23, 95% CI: 1.13–1.33, P < 0.001). Subgroup analysis showed that the combined effect size of tree pollen exposure was OR = 1.56 (95% CI: 0.99–2.12, P < 0.001), and the effect size of grass and weed pollen exposure was OR = 1.06 (95% CI: 1.01–1.12, P < 0.001). The comprehensive effect size of literature considering air pollutants and climatic factors was OR = 1.35 (95% CI: 1.20–1.50, P = 0.034), while literature not considering these factors was OR = 1.08 (95% CI: 1.06–1.10, P = 0.156). Age subgroup analysis showed that the effect size for preschool children was OR = 1.31 (95% CI: 0.53–2.09, P = 0.156), and for school-age children was OR = 1.52 (95% CI: 1.32–1.73, P = 0.298). Sensitivity analysis and Egger's test showed no significant publication bias.ConclusionAirborne pollen is a notable risk factor for childhood asthma, and tree pollen exposure may be more dangerous than grass and weed pollen exposure. When atmospheric pollutants and meteorological conditions are considered, the association between airborne pollen and childhood asthma is more pronounced. The evidence is insufficient to support a significant age-related difference between pollen and asthma.

Objective: Airborne pollens are significant triggers of allergic rhinitis, atopic conjunctivitis, and asthma. The present study aimed to examine the patterns, quantities, and dynamic changes of airborne pollens in Phitsanulok, lower northern Thailand, during three periods, November 2006 to October 2007, August 2013 to July 2014, and August 2022 to July 2023. Materials and Methods: In 2006 to 2007, airborne pollens were collected using a Rotorod sampler positioned 1.5 to 2 meters above ground. In 2013 to 2014 and 2022 to 2023, pollens were collected using a Burkard seven-day volumetric spore trap positioned 15 meters above ground. The exposed rods and slides were stained for microscopic analysis. Meteorological data were also obtained. Results: Monthly airborne pollen counts ranged from 48 to 304 grains/m³ in 2006 to 2007, 28.1 to 110.8 grains/m³ in 2013 to 2014, and 60.7 to 151.7 grains/m³ in 2022 to 2023. Peaks occurred in February, May, and August in 2006 to 2007, December in 2013 to 2014, and February and December in 2022 to 2023. Wild grass and cultivated grass were the most and second most common pollen, respectively, across all three periods, with variations in the pollen types ranked third to tenth. Total annual rainfall from 2013 to 2014 was the lowest among the three periods. The highest temperatures and lowest humidity levels, recorded in April 2013 to 2014 and 2022 to 2023, corresponded to low pollen levels. Conclusion: The average monthly pollen count during 2022 to 2023 was lower than that recorded in 2006 to 2007 but slightly higher than in 2013 to 2014. Wild grass was the predominant pollen type over the 16-year period, with levels considered a high allergic risk.

Seasonal variability in abundance and diversity of airborne pollen grains in the foothills of the Western Himalayas

Hybrids offer a promising approach to improve crop performance because the progeny are often superior to their parent lines and they outyield inbred varieties. A major challenge in producing hybrid progeny in wheat, however, lies in the inefficient fertilization of maternal parent ovaries by airborne pollen from male donor lines. This is often attributed to suboptimal synchronization of male and female flowering, as delayed pollination can result in reproductive failure due to female stigma deterioration. To test this accepted dogma, we examined the seed set capacity of six male-sterile (MS) cultivars, each varying in the onset of stigma deterioration. To mimic a hybrid seed production scenario, MS cultivars were grown during two consecutive field seasons, and open pollination was allowed up to 15 d after flowering of the female parent using a blend of seven male fertile cultivars with varying flowering times. Detailed analysis of the temporal and spatial distribution of hybrid seed set along the spike across the six MS cultivars showed that seed production remained remarkably stable during the pollination window tested. These findings suggest sustained receptivity of stigma to pollen across all tested MS cultivars throughout the entire time course. We therefore conclude that stigma longevity does not represent a limiting factor in hybrid wheat seed production, and that breeding efforts should prioritize the study of other female traits, such as enhanced access to airborne pollen.

Associations between airborne pollen, pollen-related allergic rhinitis and blood pressure: A systematic review and meta-analysis.

Comparative study of airborne pollen in Shipai area of Guangzhou City from 1986 to 1987 and 2021 to 2022

Airborne pollen monitoring depends on the precise and reproducible detection of pollen. In Europe, the volumetric Hirst standardized approach served as the baseline for the traditional method for pollen monitoring networks, requiring highly skilled technicians and which is a labor-intensive job. That is why there is a need for new automatic methodologies to solve those problems. This study evaluates and compares the technical characteristics of various automated pollen detection systems available on the market, providing a snapshot of the current state of technology. Particle size resolution, aspiration volume, storage capacity for high-definition particle pictures, and real-time data transfer were among the principal attributes of the systems examined. Our findings reveal that each system features unique advantages and limitations, with significant correlations between pollen concentrations detected by automatic systems and the manually operated Hirst sampler, especially with the Hund BAA-500 and Swisens Poleno devices. However, current systems require further enhancements in their classification algorithms and the development of comparable datasets for improved functionality. While this review provides an overview of the current scenario, the field is rapidly evolving, with continuous improvements and the potential for new players in the market.Graphical abstract

Over the past few decades, the detection of airborne pathogens in various indoor and outdoor settings has emerged as a crucial area of research and development. Bioaerosols, stemming from natural or industrial sources and comprising airborne organisms or their fragments, pose potential public and industrial health risks. Hence, there is a growing emphasis on achieving early and dependable detection methods for these pathogens across different environments. This project investigates some possibilities for developing cost-effective “first alert” technology capable of detecting airborne bacteria, fungi and pollen in real time. The proposed approach shows significant promise as an initial alert system capable of alerting users to the possible presence of pathogens or allergens in the air, allowing for the timely implementation of personal protective measures. Although the device cannot differentiate between specific types of bacteria, fungi or pollen, it effectively collects and retains them in a liquid sample. This allows for their precise characterization to be conducted in the nearest laboratory. Subsequently, decisions regarding the retention or removal of protective equipment can be made based on the laboratory results, with further guidance sought from public health specialists as needed.Graphical abstract

Comparison of airborne pollen and total stellate hair counts for six years between two sites in Sapporo