Daily Pollen Counts Research Articles

Annual and intradiurnal variation of dominant airborne pollen and the effects of meteorological factors in Çeşme (Izmir, Turkey).

In this present study, airborne pollen in Çeşme was investigated between February 17, 2012 and February 17, 2014 using the volumetric method. Çeşme, one of Turkey's most important tourism centers, which attracts numerous local and foreign tourists each year, is a district of Izmir, a province in the western part of Turkey. During the 2-year study, 12,905 pollen grains belonging to 64 taxa (33 arboreal, 31 non-arboreal plants) were detected. However, the 2-year data results revealed that the taxa with the pollen concentration more than 4% in the atmosphere were Cupressaceae/Taxaceae (4268 pollen, 33.07%), Olea europaea (1614 pollen grains, 12.51%), Pinaceae (1085 pollen grains, 8.41%), Quercus spp. (1081 pollen grains, 8.38%), Pistacia spp. (743 pollen grains, 5.76%), and Poaceae (557 pollen grains, 4.32%), all of which comprised 72.44% of the total count. The relationship between the daily pollen counts belonging to these six taxa and the hourly average temperature (°C), daily precipitation (mm), relative humidity (%), and wind speed (km/h) was assessed using the Spearman correlation test, and significant results were determined. During the study, the intradiurnal distribution of the aforementioned pollen varied. The highest pollen concentration was detected between 11:00 a.m. and 6:00 p.m. (first year 30.3%; second year 30.1%).

Biogeographical drivers of ragweed pollen concentrations in Europe

The drivers of spatial variation in ragweed pollen concentrations, contributing to severe allergic rhinitis and asthma, are poorly quantified. We analysed the spatiotemporal variability in 16-year (1995–2010) annual total (66 stations) and annual total (2010) (162 stations) ragweed pollen counts and 8 independent variables (start, end and duration of the ragweed pollen season, maximum daily and calendar day of the maximum daily ragweed pollen counts, last frost day in spring, first frost day in fall and duration of the frost-free period) for Europe (16 years, 1995–2010) as a function of geographical coordinates. Then annual total pollen counts, annual daily peak pollen counts and date of this peak were regressed against frost-related variables, daily mean temperatures and daily precipitation amounts. To achieve this, we assembled the largest ragweed pollen data set to date for Europe. The dependence of the annual total ragweed pollen counts and the eight independent variables against geographical coordinates clearly distinguishes the three highly infected areas: the Pannonian Plain, Western Lombardy and the Rhone-Alpes region. All the eight variables are sensitive to longitude through its temperature dependence. They are also sensitive to altitude, due to the progressively colder climate with increasing altitude. Both annual total pollen counts and the maximum daily pollen counts depend on the start and the duration of the ragweed pollen season. However, no significant changes were detected in either the eight independent variables as a function of increasing latitude. This is probably due to a mixed climate induced by strong geomorphological inhomogeneities in Europe.

Pollen exposure and hospitalization due to asthma exacerbations: daily time series in a European city

Exposure to pollen can contribute to increased hospital admissions for asthma exacerbation. This study applied an ecological time series analysis to examine associations between atmospheric concentrations of different pollen types and the risk of hospitalization for asthma in London from 2005 to 2011. The analysis examined short-term associations between daily pollen counts and hospital admissions in the presence of seasonal and long-term patterns, and allowed for time lags between exposure and admission. Models were adjusted for temperature, precipitation, humidity, day of week, and air pollutants. Analyses revealed an association between daily counts (continuous) of grass pollen and adult hospital admissions for asthma in London, with a 4–5-day lag. When grass pollen concentrations were categorized into Met Office pollen ‘alert’ levels, ‘very high’ days (vs. ‘low’) were associated with increased admissions 2–5 days later, peaking at an incidence rate ratio of 1.46 (95%, CI 1.20–1.78) at 3 days. Increased admissions were also associated with ‘high’ versus ‘low’ pollen days at a 3-day lag. Results from tree pollen models were inconclusive and likely to have been affected by the shorter pollen seasons and consequent limited number of observation days with higher tree pollen concentrations. Future reductions in asthma hospitalizations may be achieved by better understanding of environmental risks, informing improved alert systems and supporting patients to take preventive measures.

大分大学医学部 (大分県由布市挟間町) におけるスギ花粉飛散予測の検証

We investigated the accuracy of the prediction of Japanese cedar-pollen dispersion at the Oita University Faculty of Medicine Complex for use in future prediction models. We compared the predicted and actual total pollen counts per year, the initial day of pollen scattering, and the daily pollen counts from 2005 to 2014. Total pollen counts per year were predicted by the amount of sunshine in the Hita area, which was considered to be the source of pollen in our previous study, during the previous July. The initial day of pollen scattering was predicted using the variation pattern in air temperature. Daily pollen counts were predicted by performing a multivariate analysis using the type-II quantification method. The differences between the actual and predicted total pollen counts per year increased after 2011. The correlation coefficient between the total pollen count and the amount of sunshine duration in the Hita area during the previous July greatly decreased in the same period, and was surpassed by the correlation coefficient for the Nakatsu area. We speculated that the primary source of pollen had moved from the Hita refion to the Nakatsu region. The average difference between the predicted and actual initial day of pollen scattering was 3.2 days. This difference was decreased when we reanalyzed the data using the Nakatsu area as the source of pollen. With regard the prediction of the daily pollen counts, the overall accuracy was 60%-70%, but the accuracy for the full-scale scattering period was 40%-60%. Our results suggest that the prediction of atmospheric Japanese cedar-pollen dispersion must be routinely reviewed. In addition, when estimating total pollen counts and the initial day of pollen scattering, it is necessary to consider the pollen source area. This method must be examined further for its accuracy in predicting the daily pollen counts.

Regional and seasonal variation in airborne grass pollen levels between cities of Australia and New Zealand.

Although grass pollen is widely regarded as the major outdoor aeroallergen source in Australia and New Zealand (NZ), no assemblage of airborne pollen data for the region has been previously compiled. Grass pollen count data collected at 14 urban sites in Australia and NZ over periods ranging from 1 to 17 years were acquired, assembled and compared, revealing considerable spatiotemporal variability. Although direct comparison between these data is problematic due to methodological differences between monitoring sites, the following patterns are apparent. Grass pollen seasons tended to have more than one peak from tropics to latitudes of 37°S and single peaks at sites south of this latitude. A longer grass pollen season was therefore found at sites below 37°S, driven by later seasonal end dates for grass growth and flowering. Daily pollen counts increased with latitude; subtropical regions had seasons of both high intensity and long duration. At higher latitude sites, the single springtime grass pollen peak is potentially due to a cooler growing season and a predominance of pollen from C3 grasses. The multiple peaks at lower latitude sites may be due to a warmer season and the predominance of pollen from C4 grasses. Prevalence and duration of seasonal allergies may reflect the differing pollen seasons across Australia and NZ. It must be emphasized that these findings are tentative due to limitations in the available data, reinforcing the need to implement standardized pollen-monitoring methods across Australasia. Furthermore, spatiotemporal differences in grass pollen counts indicate that local, current, standardized pollen monitoring would assist with the management of pollen allergen exposure for patients at risk of allergic rhinitis and asthma.

A contribution to the knowledge of Cupressaceae airborne pollen in the middle west of Spain

This study investigates the pollen of Cupressaceae in the atmosphere of Salamanca during the years 2000–2007. Annual variations in the concentration of pollen in the atmosphere were analysed by the volumetric method using Hirst spore trap. From a quantitative point of view, Cupressaceae is the third most abundant airborne taxa in the city of Salamanca where it constitutes 11 % of the total pollen content as a mean value, displaying an increase in its atmospheric pollen index during the 8 years studied. This pollen type was mainly detected in the atmosphere during winter season, with an atmospheric pollen season registered between late January and June and maximum concentrations detected in late February and early March. The intradiurnal pattern reached a higher hourly concentration peak in the central hours of the day. Cupressaceae pollen concentrations exceeded known thresholds on more days in the last 4 years studied. The correlations obtained between daily pollen counts and different meteorological parameters showed that the airborne presence of this pollen type is positively associated with temperature during winter months. The results could be useful to improve the knowledge of this pollen type in the atmosphere and to prevent symptoms of allergic reactions in pollen-sensitive people.

Allergy test: Seasonal allergens and performance in school

Seasonal pollen allergies affect approximately 1 in 5 school age children. Clinical research has established that these allergies result in large and consistent decrements in cognitive functioning, problem solving ability and speed, focus and energy. However, compared to air pollution, the impact of pollen and seasonal allergies on achievement in schools has received less attention from economists. Here, I use data on daily pollen counts merged with school district data to assess whether variation in the airborne pollen that induces seasonal allergies is associated with performance on state reading and math assessments. I find substantial and robust effects: A one standard deviation in ambient pollen levels reduces the percent of 3rd graders passing ELA assessments by between 0.2 and 0.3 standard deviations, and math assessments by between about 0.3 and 0.4 standard deviations. I discuss the empirical limitations as well as policy implications of this reduced-form estimate of pollen levels in a community setting.

Spatial differentiation of airborne arboreal pollen in Lublin (Poland)

The study compared the occurrence of airborne pollen of 7 arboreal taxa (<em>Corylus</em>, <em>Alnus</em>, Cupressaceae/Taxaceae, <em>Populus</em>, <em>Fraxinus</em>, <em>Betula</em> and <em>Carpinus</em>) during the period 2007–2009 from two sites in Lublin city, SE Poland. The sites differed in the character of building development and surrounding vegetation. Pollen monitoring was conducted by the volumetric method using two Hirst-type samplers. Daily and intradiurnal pollen counts were determined. For all the taxa, Spearman’s test revealed statistically significant positive correlations between daily pollen fluctuations at two sites. Nevertheless, the Mann–Whitney <em>U</em>-test showed differences for Cupressaceae/Taxaceae, <em>Fraxinus</em>, <em>Populus</em> and <em>Corylus</em> between sites. The intradiurnal pattern of pollen concentration was characterized by high variation. Cupressaceae/Taxaceae and <em>Populus</em>, clearly differed in hourly pollen concentrations at both sites. Moreover, in the case of <em>Betula</em> and <em>Alnus</em> it was shown that a part of pollen recorded in Lublin can originate from long-distance transport. High pollen concentrations can be expected at different hours of the day. The lowest average pollen concentrations at both sites were found during morning hours at 5 and 6 a.m. Based on the obtained results, it can be concluded that data from a single pollen-sampling device are not representative of some taxa in the particular districts of the city. Average data obtained from at least two pollen samplers could provide optimum results.

Correlating regional aeroallergen effects on internet search activity.

To investigate the correlation between the change in regional aeroallergen levels and Internet search activity related to allergies. A retrospective time series analysis using a graphical analytical approach and statistical modeling was used. Tertiary academic hospital setting. There were no specific enrolled subjects. Data from Google Trends were obtained (google.com/trends) for the following search terms: "allergy," "allergies," "pollen," "runny nose," "congestion," and "post nasal drainage." Daily pollen and mold spore count data were obtained for the same period from throughout Texas. Graphical analysis, correlation, and autoregressive integrated moving average (ARIMA) were employed to assess the relationship between aeroallergens on Google search activity. A strong positive correlation was observed between observed pollen counts and search activity for the terms "allergies" (r pollen = 0.798), "allergy" (r pollen = 0.781), and "pollen" (r pollen = 0.849). Symptom term searches were weakly correlated with pollen and mold counts. Also, ARIMA modeling supported the relationships indicated by the correlations. Search activities for surrogate terms such as "allergy," "allergies," and "pollen" correlate strongly with observed pollen counts but not mold counts. These data demonstrate the usefulness of Google Trends search data in assessing regional disease burdens and offer insight into how the public seeks information about their own illness.

Plants remember past weather: a study for atmospheric pollen concentrations of Ambrosia, Poaceae and Populus

After extreme dry (wet) summers or years, pollen production of different taxa may decrease (increase) substantially. Accordingly, studying effects of current and past meteorological conditions on current pollen concentrations for different taxa have of major importance. The purpose of this study is separating the weight of current and past weather conditions influencing current pollen productions of three taxa. Two procedures, namely multiple correlations and factor analysis with special transformation are used. The 11-year (1997–2007) data sets include daily pollen counts of Ambrosia (ragweed), Poaceae (grasses) and Populus (poplar), as well as daily values of four climate variables (temperature, relative humidity, global solar flux and precipitation). Multiple correlations of daily pollen counts with simultaneous values of daily meteorological variables do not show annual course for Ambrosia, but do show definite trends for Populus and Poaceae. Results received using the two methods revealed characteristic similarities. For all the three taxa, the continental rainfall peak and additional local showers in the growing season can strengthen the weight of the current meteorological elements. However, due to the precipitation, big amount of water can be stored in the soil contributing to the effect of the past climate elements during dry periods. Higher climate sensitivity (especially water sensitivity) of the herbaceous taxa (Ambrosia and Poaceae) can be definitely established compared to the arboreal Populus. Separation of the weight of the current and past weather conditions for different taxa involves practical importance both for health care and agricultural production.

Particulate matter modifies the association between airborne pollen and daily medical consultations for pollinosis in Tokyo

Pollen from Japanese cedar (sugi) and cypress (hinoki) trees is responsible for the growing prevalence of allergic rhinitis, especially pollinosis in Japan. Previous studies have suggested that air pollutants enhance the allergic response to pollen in susceptible individuals. We conducted a time-stratified case-crossover study to examine the potential modifying effects of PM2.5 and suspended particulate matter (SPM) on the association between pollen concentration and daily consultations for pollinosis. A total of 11,713 daily pollinosis cases (International Classification of Diseases, ICD-10, J30.1) from January to May, 2001–2011, were obtained from a clinic in Chiyoda, Tokyo. Daily pollen counts and the daily mean values of air pollutants (PM2.5, SPM, SO2, NO2, CO, and O3) were collected from monitoring stations across Tokyo. The effects of pollen were stratified by the level of PM2.5 and SPM to examine the interaction effect of pollen and particulate pollutants. We found a statistically significant interaction between pollen concentration and PM2.5/SPM. On days with a high level of PM2.5 (>95th percentile), an interquartile increase in the mean cumulative pollen count (an average of 28 pollen grains per cm2 during lag-days 0 to 5) corresponded to a 10.30% (95%CI: 8.48%–12.16%) increase in daily new pollinosis cases, compared to 8.04% (95%CI: 7.28%–8.81%) on days with a moderate level of PM2.5 (5th–95th percentile). This interaction persisted when different percentile cut-offs were used and was robust to the inclusion of other air pollutants. A similar interaction pattern was observed between SPM and pollen when a less extreme cut-off for SPM was used to stratify the effect of pollen. Our study showed the acute effect of pollen was greater when the concentration of air particulate pollutant, specifically PM2.5 and SPM, was higher. These findings are consistent with the notion that particulate air pollution may act as an adjuvant that promotes allergic disease (i.e. pollinosis).

The effects of the current and past meteorological elements influencing the current pollen concentrations for different taxa.

BackgroundIt is an important issue to separate the current and past components of the meteorological parameters influencing the current pollen concentration for different taxa. For this purpose a new statistical procedure, factor analysis with special transformation is introduced. The data set used covers an 11-year period (1997–2007) including daily pollen counts of 19 taxa and 4 climate variables (mean temperature, precipitation amount, global solar flux and relative humidity).ResultThe taxa examined can be classified into three groups, namely arboreal deciduous (AD), arboreal evergreen (AE) and herbaceous (H) taxa. It was found that a better comparison can be established if the taxa are separated within each group according to the starting month of their pollen season. Within the group of AD taxa, Alnus, Populus and Ulmus are marked by a late summer – early autumn peak of the role of past meteorological elements exceeding the role of the current ones almost all over the pollen-free period. For Juglans, Morus, Platanus and Quercus, the major weights of the current meteorological elements in the spring and early summer show the most characteristic contribution to the pollen production. For AE taxa, the picture is no clear. For H taxa, the curves of Cannabis, Plantago, Rumex and Urtica indicate the most equalized course of weights. Ambrosia, Artemisia and Chenopodiaceae comprise the highest weights of the past weather conditions of all taxa until at least three months before the start of the pollination. Interactions between the phyto-physiological processes and the meteorological elements are evaluated.ConclusionSeparation of the weight of the current and past weather conditions for different taxa involves practical importance both for health care and agricultural production.

Magnitude of efficacy measurements in grass allergy immunotherapy trials is highly dependent on pollen exposure

BackgroundThe objective was to evaluate the association between grass pollen exposure, allergy symptoms and impact on measured treatment effect after grass sublingual immunotherapy (SLIT)-tablet treatment.MethodsThe association between grass pollen counts and total combined rhinoconjunctivitis symptom and medication score (TCS) was based on a post hoc analysis of data collected over six trials and seven grass pollen seasons across North America and Europe, including 2363 subjects treated with grass SLIT-tablet or placebo. Daily pollen counts were obtained from centralized pollen databases. The effect of treatment on the relationship between the TCS and pollen counts was investigated, and the relative difference between grass SLIT-tablet and placebo as a function of average grass pollen counts was modelled by linear regression.ResultsThe magnitude of treatment effect based on TCS was greater with higher pollen exposure (P < 0.001). The relative treatment effect in terms of TCS for each trial was correlated with the average grass pollen exposure during the first period of the season, with predicted reduction in TCS = 12% + 0.35% × pollen count (slope significantly different from 0, P = 0.003; R2 = 0.66). Corresponding correlations to the entire grass pollen season and to the peak season were equally good, whereas there was a poor correlation between difference in measured efficacy and pollen exposure during the last part of the season.ConclusionsIn seasonal allergy trials with grass SLIT-tablet, the observed treatment effect is highly dependent on pollen exposure with the magnitude being greater with higher pollen exposure. This is an important relationship to consider when interpreting individual clinical trial results.

A comparative study on the effects of altitude on daily and hourly airborne pollen counts

The concentration of pollen grains in the air was studied using two aerobiological volumetric Hirst-type spore traps, one at ground level and the other at a height of 16 m on a terrace. The study was carried out between 2009 and 2011, from March to June in Badajoz (SW Spain). Intradiurnal and daily pollen counts were compared with both, different meteorological parameters and the distribution of local pollen sources. Forty-six pollen types were identified and 89 % of the total grains corresponded to Quercus, Poaceae, Olea, Pinaceae and Plantago pollen types, in descending order. The mean height ratio of the daily pollen count was 1.02. Significant correlations were observed when comparing daily pollen counts for predominant pollen types at both levels. The comparisons have shown significant differences in the daily pollen count between the two samplers in the case of Olea and Pinaceae, but not for Quercus, Poaceae and Plantago. Similar results were obtained using the intradiurnal airborne pollen database. No significant correlation has been found between pollen count and the different meteorological parameters, showing no dependence on height. These differences of Olea and Pinaceae may be explained in part by the uneven distribution of the pollen sources and the disturbance by nearby buildings. The temporal variation patterns between the two sites were similar; however, taking into account the average of the data, the higher values were obtained first at the ground level and later at 16 m.

The associations between daily spring pollen counts and asthma emergency department visits syndrome in New York City

The associations between daily spring pollen counts and asthma emergency department visits syndrome in New York City

A side-by-side comparison of Rotorod and Burkard pollen and spore collections

BackgroundThe Rotorod sampler and Burkard spore trap are 2 devices commonly used to quantify airborne particles. ObjectiveTo evaluate the differences in collections between the 2 devices for a wide range of plant pollens and fungal spores. MethodsPollens and spores were collected simultaneously with each device on 167 days during a 1-year period. ResultsThe Burkard yielded significantly higher total and individual mold spore counts. It yielded statistically higher total grass, total weed, and Urticaceae daily pollen counts, although the absolute differences were small. Daily counts were positively correlated between the 2 devices for the most abundant pollens and mold spores. ConclusionThe Burkard spore trap collects many more mold spores than the Rotorod over a wide variety of species. The Burkard also yielded higher total grass, total weed, and Urticaceae daily pollen counts. Despite these differences, however, either device can be used to follow trends in the most abundant pollen and mold spores.

The effect of the meteorological factors on the Alnus pollen season in Lublin (Poland)

Alder pollen seasons and the effect of meteorological conditions on daily average pollen counts in the air of Lublin (Poland) were analysed. Alnus pollen grains reach very high concentrations in the atmosphere of this city during the early spring period and the parameters of pollen seasons were very different in the particular years studied. The pollen season lasted on average one month. The highest variation was observed for the peak value and the Seasonal Pollen Index (SPI). The pollen seasons, which started later, had shorter duration. Peak daily average pollen counts and SPI value were higher during the shorter seasons. Similarities in the stages of pollen seasons designated by the percentage method depended on the start date of the pollen season. Season parameters were mainly correlated with thermal conditions at the beginning of the year. Regression analysis was used to predict certain characteristics of the alder pollen season. The highest level of explanation of the variation in Alnus pollen season start and peak dates was obtained in the model using mean temperature in February. The obtained regression models may predict 82% of the variation in the pollen season start date, 73% of the variation in the duration, and 62% in the peak date.

Analysis of airborne allergenic pollen spectrum for 2009 in Timişoara, Romania

The objective of this investigation was to identify the overall pollen types and, more particularly, the allergenic pollen content in the investigated area and then to explore their seasonal variations. The measurement point was located in the Timisoara city, Romania. A Lanzoni volumetric trap was used for sample collection. Duration of the pollen season of allergenic plants and respective variation in airborne pollen concentration are presented in the pollen calendar for the year 2009. Among the identified pollen of 23 types, 20 were allergenic: Taxaceae/Cupressaceae, Alnus sp., Fraxinus sp., Betula sp., Corylus sp., Carpinus sp., Salix sp., Populus sp., Ulmus sp., Juglans sp., Quercus sp., Pinaceae, Tilia, Poaceae, Urticaceae, Chenopodiaceae/Amaranthaceae, Rumex sp., Plantago sp., Artemisia sp., Ambrosia sp. These species prevail throughout almost the entire pollen season, from February–October, accounting for 87.03 % of the total pollen count. The greatest diversity of pollen types is detected in the months of spring. The summer months were characterized mostly by non-arboreal pollen types. In late summer and early autumn, Ambrosia airpollen was the most abundant in the atmosphere. The relationships between pollen concentrations and nine meteorological parameters are presented too. To analyze the correlation between pollen data and variables, the Spearman rank correlation coefficient was used. The correlation analysis of daily pollen counts and meteorological parameters showed that arboreal pollen and non-arboreal pollen counts were significantly correlated with temperature. The prevalence of pollen sensitization resulted to be very high in our patients with respiratory symptoms.

Analysis of Chenopodiaceae-Amaranthaceae airborne pollen in Salamanca, Spain

Chenopodiaceae-Amaranthaceae pollen represents an allergenic risk for pollen-sensitive people. The aim of this study was to describe the Chenopodiaceae-Amaranthaceae pollen dynamics in the atmosphere of Salamanca (mid-west Spain) during the years 2000-2007. Measurements were performed by the volumetric method using a Burkard spore trap located in the urban centre at the height of 20 m above ground level. This pollen type was mainly detected in the atmosphere between late spring and late summer, with an Atmospheric Pollen Season (APS) registered between late May and early October and maximum concentrations detected in August. The intradiurnal pattern, calculated by means of 3 different methods, reached a higher hourly concentration percentage in the second half of the day. The correlations obtained between daily pollen counts and different meteorological parameters showed that the airborne presence of this pollen type is associated positively with temperature and negatively with rainfall and relative humidity. In terms of the known threshold (10-15 pollen/m^3), Chenopodiaceae-Amaranthaceae pollen concentrations were found to exceed this threshold on 1 day in the years 2002, 2005, and 2007, and on 12 days in 2006. The results can be utilised to prevent symptoms of allergic reactions to this pollen type and to improve quality of life during seasonal allergic diseases in Chenopodiaceae pollen-sensitive people.

NEW POLLEN INDEX FOR CHARACTERIZING POPULATION EXPOSURE TO AIRBORNE POLLEN LOAD AT DIFFERENT GEOGRAPHICAL LEVELS

Background and Aims: The ongoing spread of Ambrosia artemisiifolia in Europe is an increasing problem for human health and as an agricultural and non-agricultural weed. Hungarian Aerobiological Network (HAN) has monitored the airborne pollen of ragweed for 18 years, these data are a sound basis to create indicators to monitor the changes of the ragweed pollen season in time and space and the population exposure. Methods: HAN has 18 monitoring sites out of which 8 sites were selected being representative for the characteristic macroclimate types of the country. The relevant population was defined as the population living around the monitoring site in a circle of 17.5 km. The start and end of the pollen season (1% resp. 99% of cumulative daily pollen count) was defined, daily pollen concentration were categorised into 7 groups (0-9, 10-29, 30-99, 100-299, 300-499, ≥500 pollen grains/m3 resp. missing value). Two sub-indices were defined and computed by year. Rate of time of population exposure to pollen concentration categories (TR) and rate of population (PR) exposed to different categories of daily pollen concentration at selected monitoring sites during the pollen season TR(x) and PR(x) indicate, what percentage of the total population is exposed to a given pollen concentration category (x) in what percentage of days of the total pollen season. Results: Based on selected pollen data for 2010, 52.2% of the population was exposed to daily pollen concentration over 30 grains/m3 (evoking allergic symptoms in every patient) during 40.8% of days of the season (32 days). 3.7% of the population was exposed to ≥500 grains/m3 (extremely high category) for 4.8% of days. Conclusions: In the future the indices can be used to examine spatial differences and time trends. This project is supported by the New Hungary Development Plan (Project ID:TÁMOP-4.2.1/B-09/1/KMR-2010-0005).