Evaluation of the efficiency of the Coriolis air sampler for pollen detection in South Europe

The Coriolis δ air sampler is a new volumetric air sampler, dedicated to outdoor monitoring of airborne biological particles, including pollen and spores. In the present work, the performance of the Coriolis in the collection of pollen grains was evaluated in comparison with a Hirst spore trap, the most frequently used trap in aerobiological studies, in two cities of South Europe, Evora (Portugal) and Córdoba (Spain). Both concentration values are compared, and statistical analysis was carried out. The present study indicated that, in general, pollen counts for all taxa detected with the Hirst trap were higher than those detected with the Coriolis δ in both cities. In Córdoba, significant differences were detected for all taxa except for Cupressus, Olea and Pinus, while in Evora significant differences were noted for all except Pinus and Poaceae. Differences were particularly marked in species flowering during April and May. In spite of theses differences, Spearman correlation test results showed that the relationship between Hirst and Coriolis curves was always positive and significant (p > 0.01). Regards to the number of detected taxa, the results showed greater diversity for the Hirst sampler in both cities.     

Status of airborne spores and pollen in a coir factory in Kerala,India

The prevalence of airborne fungal spores and pollen grains in the indoor and outdoor environments of a coir factory in Thiruvananthapuram district of Kerala state, India was studied using the Burkard Personal Sampler and the Andersen 2-stage Sampler for 2 years (September 1997 to August 1999). The concentration of pollen grains was remarkably lower than that of fungal spores (ratio of 1:28). There was no large difference in the concentrations and types of fungal spores between the indoor and outdoor environments, with 26 spore types found to be present indoors and 27 types outdoors; of these, 22 were common to both the environments. Aspergillus/Penicillium, Cladosporium, ‘other basidiospores’ and ascospores were the dominant spore types. The total spore concentration was highest in February and lowest in September, and it was significantly higher in 1998–1999 than in 1997–1998. Twenty viable colony-forming types were isolated from inside the coir factory. The most dominant viable fungi isolated were Penicillium citrinum, Aspergillus flavus and Aspergillus niger. The total pollen concentration was higher in the outdoor environment of the coir factory than indoors, with 15 and 17 pollen types, respectively. Grass and Cocos nucifera pollen types were dominant. The dominant spore and pollen types trapped in the two environments of the coir factory are reportedly allergenic and, consequently, workers are at risk of catching respiratory/allergic diseases.     

Fern spore and pollen airspora profile of Singapore

Monitoring atmospheric fern spore and pollen loads in Singapore was initiated in June 1990. Aside from the more numerous fungal spores, fern spores and pollen grains made up 6.2–8.6% and 4.4–5.4% of the total airspora sampled, respectively. The most frequently encountered fern spores, in descending order, were those of Nephrolepis auriculata, Dicranopteris linearis, Stenochlaena palustris, Asplenium nidus, Pteridium aquilinum, and Dicranopteris curranii. For pollen grains, the most frequently encountered, in descending order, were Elaeis guineensis, Casuarina equisetifolia, Acacia auriculiformis, Kyllingia polyphylla, Podocarpus, and Poaceae pollen grains. Seasonal patterns for individual fern spore or pollen types were discernible despite the relatively uniform tropical climate in Singapore. The fern spore and pollen calendar for the period 1991–1995 was compared to that of 2005–2006 as a follow-up study to keep abreast with the rapidly changing landscape of Singapore. Diurnal patterns showing a late morning to afternoon peak period were seen in fern spores, while the peak period was in the morning for pollen types studied with the exception to oil palm pollen. Additionally, association between fern spore and pollen counts and local meteorological conditions were also analyzed and found to be highly correlated. This study has thus identified the fern spores and pollen airspora components, and determined the calendars, as well as diurnal profiles of the Singapore airspora and provides invaluable information for allergy studies by highlighting the trigger sources present in the environment.     

Comparative particle recoveries by the retracting rotorod,rotoslide and Burkard spore trap sampling in a compact array

An array comprising 4 intermittent (retracting) rotorods, 3 (swingshield) rotoslides and one Burkard (Hirst) automatic volumetric spore trap was operated on an urban rooftop during 70 periods of 9, 15 or 24 hours in late summer. Standard sampling procedures were utilized and recoveries of pollens as well as spores ofAlternaria, Epicoccum, Pithomyces andGanoderma species compared. Differences between paired counts from each sampler type showed variances increasing with levels of particle prevalence (and deposition). In addition, minimal, non-random, side-to-side and intersampler differences were noted for both impactor types. Exclusion of particles between operating intervals by rotoslides and rotorods was virtually complete. Spore trap recoveries for all particle categories, per m³, exceeded those by both impactors. The greatest (7-fold) difference was noted for the smallest type examined (Ganoderma). For ragweed pollen, an overall spore trap/impactor ratio approached 1.5. Rain effects were difficult to discern but seemed to influence rotoslides least. Overall differences between impactors were quite small but generally favored the rotoslide in this comparison. Our data confirm the relative advantages of suction traps for small particles. Both impactors and spore traps are suited to pollen and large spore collection, and, with some qualification, data from both may be compared.     

Summer airborne mycoflora of Timişoara (Romania) and relationship to meteorological parameters

The present aeromycological investigation was undertaken to study atmospheric fungal spores in Timi?oara (western Romania). This study was carried out using a Hirst type volumetric sampler. The study revealed the existence of a rich airborne mycoflora. The atmospheric fungal spores were classified and evaluated into three groups (‘major’, ‘minor’ and ‘sporadic’) depending upon their catch percentage in the air. Cladosporium/Fusarium/Leptosphaeria-group, Alternaria, Helminthosporium airborne fungal spores and airborne fungal fragments regularly recorded (frequency 100% of days). Cladosporium accounted for 81.09% of the outdoor fungal spores. The airborne fungal fragments have been identified as abundant in our geographic area. Spearman’s correlations were applied to meteorological parameters and airborne fungal spore concentrations. In addition, correlations were calculated between the fungal spore concentrations and the meteorological variables from the previous day. A total of eleven weather factors were selected for this investigation. Following Spearman’s correlations, I identified two patterns of behaviour: most of the airborne fungal spores prefer cloudiness, lower near-surface soil temperature, lower atmospheric pressure, higher relative humidity and precipitation (pattern A) while other spore concentrations favour increased sunshine, higher near-surface soil temperature and dry conditions (pattern B). The behaviour of some fungal spores during the warm season has proven unclear (pattern C). This study demonstrates the need for investigations throughout the year and the evaluation with complementary statistical methods, regarding the correct interpretation of airborne mycoflora relationships with meteorological parameters.     

Risk of pollen allergy in Nerja (southern Spain): a pollen calendar

An aeropalynological study was carried out in the atmosphere of the city of Nerja (southern Spain) during a period of 4 years (2000–2003), using a Hirst type volumetric pollen trap. An annual pollen index of 59,750 grains, on average, was obtained with 80–85% of the total pollen recorded from February to May, with Pinus, Olea, Urticaceae, Cupressaceae, Quercus and Poaceae being the principal pollen producers in abundance order. A total of 29 pollen types that reached a 10-day mean equal to or greater than 1 grain of pollen per m³ of air is reflected in a pollen calendar. The results were compared with those obtained for nearby localities and a correlation analysis was made between the daily fluctuations of the main pollen types and total pollen, and meteorological parameters (temperature, rainfall and hours of sun). The daily, monthly and annual values reached by the most important pollen types from an allergenic point of view (Olea, Urticaceae and Poaceae) confirms Nerja as a high-risk locality for the residents and the numerous tourists who visit the area.     

Atmospheric pollen and fungal spores in Hamilton in 1972 estimated by the Hirst automatic volumetric spore trap

A knowledge of the atmospheric pollen and fungal spores is necessary for the diagnosis and management of extrinsic rhinitis and asthma. The Hirst automatic volumetric spore trap has been used for the first time in Canada to identify the quantitative and seasonal incidence of these particles. The trap is easy to operate and has several advantages over the previously used gravity samplers. Tree, grass and ragweed pollens occurred in short, well-defined seasons. Fungal spores greatly outnumbered pollen by 120 to one, and occurred in long, ill-defined seasons. They included large numbers of small basidiospores and ascospores which have previously not been detected in Canada. The latter have not been considered as potential allergens; their clinical importance requires investigation.     

Airborne pollen and spores on the Arctic island of Jan Mayen

A survey of airspora collected on Jan Mayen, an isolated North Atlantic island (71°N, 8°30′W), using a Burkard seven-day volumetric trap from 24th April to 31th August, 1988, revealed only very small concentrations. A total of 10 different pollen types were recorded, constituting a seasonal sum of 29 pollen grains. The local pollen season was confined to July, with Oxyria digna and Salix as the most numerous pollen types recorded. Exotic pollen grains, namely Betula, Pinus and Castanea type, were recorded in three periods during June and July. Studies of back trajectories indicate North America and/or Iceland and Greenland as possible source areas for the Betula pollen. There were more diatoms than pollen in the local airspora. Fungal spores mainly occurred in late July and August. Cladosporium constituted less than 5% of the total seasonal sum of fungal spores, while basidiospores contributed nearly 12%. The highest diurnal average of Cladosporium was 27 spores m^?3 air. The seasonal maximum of unidentified fungal spores reached a diurnal average of 639 spores m^?1 air on 27th August.     

Selected airborne allergenic fungal spores and meteorological factors in Szczecin,Poland, 2004–2006

Airborne fungal spore concentrations in Szczecin, Poland, were studied between 2004 and 2006 with the objective of determining a seasonal variation in the concentrations of selected fungal spore types in relation to meteorological parameters. The presence of spores of five taxa, namely, Cladosporium, Ganoderma, Alternaria, Leptosphaeria and Didymella, was recorded using a volumetric method (Hirst type). Fungal spores were present in the air in large numbers during the summer, with the highest concentrations recorded mainly in June, July and August. The peak concentrations of two of the studied spore types, Ganoderma and Alternaria, occurred in August, while the concentrations of Cladosporium, Leptosphaeria and Didymella spores were the highest in July. Multiple regression analysis was performed for three fungal seasons—2004, 2005 and 2006. Spore concentration was found to be positively correlated with the minimum temperature. For some spore types, there was also a significant correlation between concentrations, relative humidity and rain.     

Relationship between indoor and outdoor airborne fungal spores, pollen, and (1→3)-β-D-glucan in homes without visible mold growth

In this exploratory study, indoor and outdoor airborne fungal spores, pollen, and (1→3)-β-D-glucan levels were determined through long-term sampling (24-h) using a Button Personal Inhalable Aerosol Sampler. The air samples were collected in five Cincinnati area homes that had no visible mold growth. The total count of fungal spores and pollen in the collected samples was conducted under the microscope and Limulus Amebocyte Lysate (LAL) chromogenic assay method was utilized for the determination of the (1→3)-β-D-glucan concentration. For the combined number concentration of fungal spores and pollen, the indoor and outdoor geometric mean values were 573 and 6,435 m⁻³, respectively, with a geometric mean of the Indoor/Outdoor (I/O) ratio of .09. The geometric means of indoor and outdoor (1→3)-β-D-glucan concentrations were .92 and 6.44 ng m⁻³, respectively, with a geometric mean of the I/O ratio equal to .14. The I/O ratio of (1→3)-β-D-glucan concentration was found to be marginally greater than that calculated based on the combined number concentration of fungal spores and pollen. This suggests that (1→3)-β-D-glucan data are affected not only by intact spores and pollen grains but also by the airborne fragments of fungi, pollen, and plant material, which are ignored by traditional enumeration methodologies. Since the (1→3)-β-D-glucan level may elucidate the total exposure to fungal spores, pollen, and fungal fragments, its I/O ratio may be used as a risk marker for mold and pollen exposure in indoor environments.     

Airborne pollen and spores’ deposition in alveolar tissues as a tool in drowning forensic diagnosis

We report the results of a histological study of lung samples where an unusual quantity of airborne pollen and fungal spores was found in drowned rats. Pollen and spores were found in lungs of drowned rats but not in the post-mortem submerged ones. Another control group consisting of rats that underwent 60 min exposure to a highly pollen-loaded atmosphere also recorded negative for the presence of pollen or fungal spores. Pollen types coincided with plants growing at the surrounding gardens flowering during the days of the experiment, performed during spring, that were detected by the aerobiological trap located at the city. The pollen observed at the lower airways’ tissues were Chenopodiaceae, Cupressus, Ericaceae, Jasminum, Olea europaea, Plantago, Pinus, Poaceae, Quercus and Urticaceae. Regarding fungal spores Alternaria, Aspergillus, Cladosporium cladosporoides, Cladosporium herbarum, Leptosphaeria, Polythrincium and Phitomyces. Pollen and spores’ penetration into deeper regions of the respiratory tract is an unusual phenomenon not happening in regular breathing conditions. Our results revealed that these particles appeared in a significant number in lung samples of drowned animals probably pushed down from upper airways by the force of water inhalation during drowning. Their presence into alveolar spaces offer a useful forensic evidence in doubtful drowning autopsies, favoured by the characteristic of the sporopollenin (pollen wall) and chitin (fungal spore wall) resistance. Moreover, the presence of these particles in alveoli areas of drowned bodies can help forensics to obtain information about pre-mortem dates and places.

     

A seven-day volumetric spore trap for use within buildings

The Burkard Volumetric spore trap, designed to operate for seven days continuously in the field, was modified to sample still air within buildings. The efficiency with which spores of Lycopodium clavatum and Agaricus bisporus were trapped at two rates of suction was determined. Spore distribution within traces and deposition on surfaces not beneath the orifice were assessed. In an appendix catches of four spore types by the Hirst and Burkard (field model) spore traps operating over mown grass were compared.     

Artificial neural network model of the relationship between <Emphasis Type="Italic">Betula</Emphasis> pollen and meteorological factors in Szczecin (Poland)

Birch pollen is one of the main causes of allergy during spring and early summer in northern and central Europe. The aim of this study was to create a forecast model that can accurately predict daily average concentrations of Betula sp. pollen grains in the atmosphere of Szczecin, Poland. In order to achieve this, a novel data analysis technique—artificial neural networks (ANN)—was used. Sampling was carried out using a volumetric spore trap of the Hirst design in Szczecin during 2003–2009. Spearman’s rank correlation analysis revealed that humidity had a strong negative correlation with Betula pollen concentrations. Significant positive correlations were observed for maximum temperature, average temperature, minimum temperature and precipitation. The ANN resulted in multilayer perceptrons 366 8: 2928-7-1:1, time series prediction was of quite high accuracy (SD Ratio between 0.3 and 0.5, R > 0.85). Direct comparison of the observed and calculated values confirmed good performance of the model and its ability to recreate most of the variation.     

Hourly predictive artificial neural network and multivariate regression tree models of <Emphasis Type="Italic">Alternaria</Emphasis> and <Emphasis Type="Italic">Cladosporium</Emphasis> spore concentrations in Szczecin (Poland)

A study was made of the link between time of day, weather variables and the hourly content of certain fungal spores in the atmosphere of the city of Szczecin, Poland, in 2004–2007. Sampling was carried out with a Lanzoni 7-day-recording spore trap. The spores analysed belonged to the taxa Alternaria and Cladosporium. These spores were selected both for their allergenic capacity and for their high level presence in the atmosphere, particularly during summer. Spearman correlation coefficients between spore concentrations, meteorological parameters and time of day showed different indices depending on the taxon being analysed. Relative humidity (RH), air temperature, air pressure and clouds most strongly and significantly influenced the concentration of Alternaria spores. Cladosporium spores correlated less strongly and significantly than Alternaria. Multivariate regression tree analysis revealed that, at air pressures lower than 1,011 hPa the concentration of Alternaria spores was low. Under higher air pressure spore concentrations were higher, particularly when RH was lower than 36.5%. In the case of Cladosporium, under higher air pressure (>1,008 hPa), the spores analysed were more abundant, particularly after 0330 hours. In artificial neural networks, RH, air pressure and air temperature were the most important variables in the model for Alternaria spore concentration. For Cladosporium, clouds, time of day, air pressure, wind speed and dew point temperature were highly significant factors influencing spore concentration. The maximum abundance of Cladosporium spores in air fell between 1200 and 1700 hours.     

Aeroallergens in northern and southern provinces of Thailand

An aeroallergen survey in two provinces, Chiangmai in the northern and Songkhla in the southern part of Thailand which are 1 500 km apart, was done in 1986 and 1987 using a rotorod sampler. The five most common pollen types and mold spores were: Chiangmai: Mold spores: Cladosporium, rust, Fusarium, Nigrospora, 1-celled spore. Pollen grains: Mimosa, wild grasses, Urticaceae, Cyperaceae, tetrad pollen. Songkhla: Mold spores: Cladosporium, rust, Nigrospora, Papularia, 1-celled spore. Pollen grains: Casuarina, Mimosa, Urticaceae, Cyperaceae, wild grass. There were definite differences in the amount and frequency of occurrences of aeroallergens between these two provinces. Furthermore, some specific pollen and mold spores, such as tetrads and Mimosa pollen, were found only in Chiangmai, and Casuarina pollen and Papularia spores only in Songkhla. These findings might be caused by the differences in geography, plantation and meteorological data.     

First results of a study on airborne sporomorps in Budapest,Hungary

The first results of an aerobiological study, with the help of a Burkard spore trap in Hungary, are reported. A pollen calendar of 1989 is presented. Out of the total identified sporomorphs, the most relevant 16 types of pollen and 10 of fungal spores are reported. We have pointed out, that in Budapest Ambrosia and Artemisia pollen and some fungal spores are particularly responsible for the long lasting allergies to pollen and spores in the autumn. The pollen frequencies and the symptom scores of patients of the Pediatrics (Semmelweis Medical School, Budapest) showed a good correlation. Weekly reports are published in a newspaper and in television.     

The aerobiological results from the 1994 cruise of the Urania (cnr) on the Adriatic. I. Pollen and spore counts on the Mediterranean sea as compared to mainland Italia

In July 1994, we were able to collect airborne fungal spores and pollen grains over the Adriatic Sea from the upper deck of the Oceanographic Ship Urania (CNR). The biological particles were collected using a modified Lanzoni VPPS 1000 sampler (operating at a flux of 10 LPM), on glycerine-gelatine coated microscopic slides. Not only were the airborne concentrations of different organisms estimated, their viability was also tested with a 1% TTC solution. Particles were collected for 60 min (i.e. a volume of 600 liters of air sampled) at every 2 h from 0600–2100 h. Up to 689 pollen grains/m³ and an impressive 48 990 spores/m³ were collected daily. Forty-two fungal taxa were identified and the most abundant spores collected were Cladosporium (82.6%), Smuts (4.8%), Ascospores (2.8%), Basidiospores (2.1%) andAlternaria (1.7%). 20 pollen taxa were identified, and the dominant pollen were Urticaceae (57.9%), Graminaceae (20.7%), Fagaceae (2.4%), Plantaginaceae (1.4%), Pinaceae (1.3%) and Eucalyptus (1.1%). The most abundant captures were done at 0800 and 1000 h (17.8 and 16.7% respectively) and at 1400 and 1600 h (13.2 and 13.8% respectively). Pollen viability per species ranged from 0 to 100%, but for the most abundant taxa, it ranged from 3.8 to 75%, and averaged 27.7%. Maximum viability was found at 0800 and 1200 h. Pollen concentrations were of the same order of magnitude as the ones found on the mainland (Brindisi, Chieti, Matera). However, its specificity was evident. Future work should therefore look more at the pollen transport process which should account for this different assemblage of pollen.     

The incidence of fungal spores in the ambient air and inside homes: Evidence from London

Little research has been carried out in London concerning fungal spore prevalence yet this information may help to elucidate geographical patterns of asthma and hay fever. Although many types of spore reach peak concentrations outdoors in late-summer, the incidences in the indoor environment may be more important through the winter because of heating and poor ventilation. Daily average concentrations of fungal spores in the ambient atmosphere were monitored with a Burkard volumetric spore trap on an exposed roof in North London from autumn 1991 until the summer of 1992. Indoor spore measurements were taken in 19 homes in the vicinity through the winter months, both by direct air sampling using a portable Burkard sampler and by dust culture. Trends in the occurrence and concentrations of fungal spores indoors and outdoors were examined. Relationships between the abundance of selected allergenic fungi and features of the houses were analysed including age of dwelling, dampness, cleanliness and presence of pets.Aspergillus andPenicillium were the most frequently occurring spore types in the homes. Overall, high spore incidence was associated with dampness and dust accumulation. The outdoor spore samples revealed generally low concentrations through the winter until March when concentrations of many types includingCladosporium, Epicoccum andAlternaria increased in abundance in response to the warmer weather. Even during the late-spring and early-summer, concentrations of most fungal spores were notably below those reported for rural sites.     

Comparisons of fungal spore distributions using air sampling at Worcester,England (2006–2010)

This study determined annual and monthly fluctuations in concentration of 20 fungal genera. The selection of taxa was made based upon their high frequency in the air as well as their well-known allergenic properties. Air samples were collected using a spore trap of Hirst design at an urban site where the trap continuously worked throughout a 5-year survey. Weather data were acquired from a meteorological station co-located with the air sampler. Influence of several meteorological parameters was then examined to reveal species–environment interactions and the potential location of fungal spore sources within the urban area. The maximum monthly sum of mean daily spore concentration varied between genera, and the earliest peaks were recorded for Pleospora sp. in April and Ustilago sp. in June. However, the majority of investigated spore types occurred in the greatest concentrations between August and September. Out of the 20 studied taxa, the most dominant genus was Cladosporium sp., which exceeded an allergenic threshold of 3000 s m^?3 40 times during very rainy years and twice as much during dry years. A Spearman’s rank test showed that statistically significant (p ≤ 0.05) relationships between spore concentration and weather parameters were mainly r _s  ≤ 0.50. Potential sources of spores at Worcester were likely to be localised outside the city area.     

Study of airborne fungal spores in Madrid, Spain

The concentration of fungal spores in the atmosphere of Madrid was recorded and analyzed for the year 2003. Airborne spores were sampled continuously with a Hirst-type spore trap located on the roof of a building of the School of Pharmacy, at about 8 m above ground level. Correlation between the mean daily spore concentrations and meteorological variables were explored by means of Spearman’s correlation analyses. Seventy spore types were identified, of which the most numerous were Cladosporium, Aspergillaceae (conidia), Coprinus, Agaricales (basidiospores), Ustilago (teliospores) and Pleospora (ascospores). These six types of spores represented more than 70% of the total. Cladosporium represented 41% of the total fungal spores, while Ustilago spores, the concentrations of which in May and June exceeded 47% of the monthly total spore count, constituted the second most important group. Spores reached their highest concentrations in the spring months, and in the autumn, mainly in October. A␣positive significant correlation was found between airborne spore counts and temperature and relative humidity. The results provide a picture of the spectrum of airborne fungal spores present in the atmosphere of Madrid and of the `peak' periods of their presence. Future studies will provide more detailed information on the seasonal dynamics of the spores most frequently found in the air as well as on the extent to which atmospheric conditions influence their release, dispersion and sedimentation processes.