Fungal Spore Concentrations Research Articles

On the results of the aeropalinospore monitoring of urban air: some features of inside and inter-seasonal variability of lower fungi spores level

Public health risks associated with molds include sensitization, allergic symptoms, irritation and/or toxicity. Sensitization to fungal allergens often occurs in patients who are hypersensitive to other groups allergens, including plant pollen. Both plants and molds are characterized by active growth in warm seasons, in temperate latitudes from April to October, which determines the presence of pollen grains of plants and mold spores in the atmospheric air during this period. This determines the needs in monitoring activity aimed to biogenic pollutants evaluation in the air of large cities where many people live compactly. The report presents the monitoring results of Alternaria, Cladosporium and other lower fungi spores in the air of Samara city in 2015 - 2020. It has been established that for the air environment of Samara, lower fungi cannot be considered as the predominant source of allergens. The high concentration of fungal spores is most often caused by fungi of Alternaria genus, which leads to the development of sensitization in 27.7% of children and 14.6% of adults in the region. The results of aeropalinospore monitoring demonstrated the lesser significance of Cladosporium genus fungi as a risk factor, or an allergens source for Samara city (Middle Volga region).

Seasonal variations of microbes in particulate matter obtained from Dhaka City in Bangladesh

ABSTRACT The present study, for the first time, evaluated the seasonal variation of PM10-associated bacterial and fungal concentrations at four locations (CARS premises, Doyel Chattar, Postogola, and Chittagong Road) in Dhaka, Bangladesh. In this study, PM10 samples were collected four times on 20.3 × 25.4 cm irradiated glass fibre filter from November 2018 to August 2019. The concentrations of total airborne bacteria (14,073 ± 8,897 CFU/m3) were found to be significantly higher (one-way ANOVA; p < 0.05) in Chittagong Road, which is known for traffic congestion, than that of the other locations. The total airborne bacterial concentrations occurred in the following descending order: winter>spring>summer>rainy. Bacillus spp. and Staphylococcus spp. were found to be the dominant species present in PM10 particles. Based on Pearson correlation analysis and stepwise multiple-regression analysis, relative humidity was found to be the most important variable controlling the concentrations of total airborne bacteria. Common fungi such as Aspergillus, Penicillium, Cladosporium and Fusarium genera were identified in the PM10 samples. The highest fungal concentration (1,974 ± 1,173 CFU/m3) was found at Chittagong Road. The total fungal spore concentrations occurred in the following descending order: summer>spring>winter>rainy. From correlation analysis and stepwise regression analysis, the temperature was found to be the most important variable influencing the concentrations of fungi in PM10 samples. A dose-rate estimation study revealed that the children were more vulnerable compared to adults with respect to exposure to bacterial and fungal dose rates. The present study has enormous implications considering the health hazards the bacterial and fungal communities pose to humans.

Seasonal Variation and Size Distribution in the Intramural Fungal Spore Concentration of Residential House in Bengaluru and their role in Respiratory Allergy

Indoor airborne fungal spores are known to have a significant role in the etiology of respiratory allergies. With the objective of identifying the indoor aeromycoflora and subsequently test the identified fungi on patients of respiratory allergy, investigations were carried out for a period of one year from March 2016 to February 2017 in the bed-room of suspected fungal allergy patient. We studied the seasonal variation and size distribution of fungal spore load in the bedroom of an old residential cum commercial area in north Bengaluru, Karnataka, India. During the period, weekly Petri plate exposures of Martin’s Rose-Bengal Streptomycin agar media revealed a total of 1120 fungal colony forming units (CFUs). The samplings illustrates highest number of CFUs species in winter. Aspergillus niger exhibited the highest prevalence followed by Penicillium chysogenum and Candida tropicalis. The study comprises the first molecular characterization of a rare, new strain of Candida tropicalis isolated from the bedrooms. This sequence has been submitted to the GeneBank and accession number received for the same.

Allergenic fungal spores in the air of urban parks

Urban green spaces, especially urban parks, are essential for the proper functioning of cities, but they can be a serious source of airborne fungal spores. Aerobiological monitoring was carried out in urban parks of different typology to estimate the risk associated with fungal spores for citizens. Volumetric method was applied with the use of portable Burkard Sampler. In the air of the studied parks, the most dominant spores are strong allergenic or considered as potentially allergenic. Cladosporium spores were found in enormous concentrations in all studied parks, and it affected the low biodiversity of fungal spores in the parks. Compared to Cladosporium, concentrations of Alternaria spores in the air were several dozen times lower, but still a risk for people who are allergic. The fungal spores spectra and their seasonal occurrence in each park were similar. The highest similarities in the patterns of the season were found in the case of Cladosporium, Alternaria, Epicoccum, and the lowest in the case of Torula and Drechslera type. Due to the fact that allergy sufferers are most often polysensitized, the period when they should limit long visits in the urban parks is July–August, when the concentration of allergenic fungal spores of many taxa is the highest.

Airborne fungal phytopathological spore assessment in three European vineyards from different bioclimatic areas

The most common fungal diseases of Vitis vinifera are powdery mildew (Erysiphe necator (Schw.) Burr.), grey mould (Botrytis cinerea Pers.) and downy mildew (Plasmopara viticola (Berk. and Curt.) Berk. and de Toni). Knowledge about the concentration of their spores in the atmosphere of the vineyard is important in order to ascertain the fungal load in the vineyard during the reproductive vine cycle. An aerobiological study was conducted in three vineyards across Europe: in North-Western Spain (Cenlle), South Spain (Montilla) and South-Eastern Poland (Rzeszow). During 2016, three Hirst-type spore traps sampled the airborne particles in each vineyard during the reproductive cycle of grapevine. The main goal of this study was the analysis and comparison of the spore concentrations in the three studied viticultural areas using different statistical tools. The most abundant spores in the vineyards atmosphere were Erysiphe necator. The highest fungal spore concentrations belonged to the North-western Spain zone, due to rainfall and temperature conditions were optimal for mould development in this area. In South Spain and South-eastern Poland, the daily spore peaks took place before than North Spain spore peaks. Average temperature, relative humidity and rainfall were the principal factors affecting the spore concentration in all zones. Redundancy Analysis showed high correlation between meteorological parameters and fungal spore concentrations.

Airborne fungal spore relationships with meteorological parameters and skin prick test results in Elazig, Turkey.

Since fungi spores have high concentrations in the atmosphere during most of the year, they have an important place in respiratory allergies. In this regard, the preparation of calendars showing fungi spore loads for residential areas has much importance in the treatment of the patients. The first aim of this study was to present the airborne fungal spore research results from Eastern Anatolia in Turkey. Then, the mold spores' relationships with the meteorological parameters and skin prick test results were also evaluated. The presence of fungal spores was investigated using a volumetric spore trap in 2018year. In this study, fungal spores within the atmosphere of the Elazığ city of Turkey was measured through the volumetric method, using a Lanzoni VPPS 2000 device (VPPS 2000 Lanzoni, Bologna, Italy), in 2018year. Annual data of temperature, humidity, precipitation and wind speed were used for comparing meteorological data with airborne fungal spore counts. In addition, 637 children who were admitted to a pediatric allergy clinic with allergic complaints were enrolled in the study. A total of 145,099 spores/m3 and 20 fungal taxa belonging to the molds were recorded. Ustilago was the predominant genus (18.10%), followed by Oidium (18.01%), Drechslera (12.82%), and Fusarium (11.60%), which were the most common fungal spores found in Elazig's atmosphere. The total mold spores in the atmosphere reached the highest level, with 28,153 spores/m3, in July (mid-summer). Moreover, we found a positive correlation between the mold spores and the temperature, but negative correlations with the humidity and wind speed. In the skin prick tests in the children with allergic complaints, we detected sensitization to Alternaria alternata in 4.4%, Cladosporium herbarum in 3.0%, Penicillium notatum in 1.4%, and Aspergillus fumigatus in 1.1%. Additionally, there was no correlation between fungal spore concentration in the atmosphere with fungal spores sensitization in the skin prick test. This study was the first aerofungal survey of the Eastern Anatolia region in Turkey; therefore, new information has been introduced in the field of aerobiology in Turkey.

Palynology from ground zero of the Chicxulub impact, southern Gulf of Mexico

Palynological analysis of Site M0077A in the Chicxulub impact crater has yielded a record of the immediate Cretaceous/Paleogene (K/Pg) recovery from ground zero of the end-Cretaceous mass extinction, followed by a record of the Paleocene–Eocene Thermal Maximum (PETM) and later Ypresian (Eocene), including the Early Eocene Climatic Optimum (EECO). Eight specimens of the dinoflagellate cyst Trithyrodinium evittii have been observed near the base of the K/Pg transitional unit; these likely represent a post-impact dinoflagellate disaster recovery assemblage deposited within several days following the impact, although the possibility that some or all of the T. evittii specimens are reworked Maastrichtian cysts cannot be fully excluded. Despite high-resolution sampling of the lowermost Paleocene successions, the oldest identifiable terrestrial palynomorphs observed in the Site M0077A core, two specimens of Deltoidospora fern spores, occur at least ∼200,000 years after the impact. Other than these occurrences, the Paleocene section is nearly barren in terms of palynomorphs, likely a result of poor preservation of organic material combined with a long recovery time for vegetation in the vicinity of the crater. Pollen and fungal spore concentrations spike in an anoxic dark shale deposited during the PETM around 56 Ma, with a diverse pollen assemblage indicating the presence of a coastal shrubby tropical forest in the geographic vicinity, likely in the Yucatán Peninsula to the south. In the marine realm, this interval is characterized by thermophilic assemblages of dinoflagellate cysts. Stratigraphically constrained cluster analysis identified four statistically robust sample clusters in the lower Eocene successions, with Malvacipollis spp. and Milfordia spp. abundances driving the highest average dissimilarity between clusters. A second notable spike in palynological concentrations above the PETM section may represent another early Eocene hyperthermal event. Pollen and plant spore concentrations generally increased during the EECO, associated with increases in terrestrial input during basin infilling.

Airborne fungal spore concentration in an industrial township: distribution and relation with meteorological parameters

Bioaerosols are reported to affect human health and cause chronic inflammation to the respiratory system, leading to its temporary or permanent damage. This study aims to perform the qualitative assessment of ambient air of Barrackpore, an industrial township of West Bengal, India, by analysing the airborne fungal spore diversity for two consecutive years. The spores of ambient air were trapped using Burkard 7-day volumetric sampler from June 2014 to May 2016. The association of major fungal taxa with environmental parameters was analysed by Spearman’s rank correlation coefficient and multiple regression analysis to identify the significant predictors. The daily average ambient fungal spore concentration was 3526.38 ± 2709.32 spores m−3. Ascospore, basidiospore, Periconia and Aspergillus/Penicillium spp. accounted for more than 65% of observed fungi, resulting in the major fungal taxa. A significant association of dominant fungi with meteorological parameters and air pollutants was observed. Additionally, stepwise multiple regression analysis pointed out that dewpoint, wind speed, particulate matter with an aerodynamic diameter ≤ 2.5(PM2.5) and atmospheric nitrogen dioxide concentration (NO2) are the significant predictors for dominant fungi. Analysis of daily ambient fungal spore concentration and determining their environmental determinants will give an insight into the ambient air quality of the residential area of Barrackpore, for the first time. The acquired data can be used to evaluate the health impact on the residents of an unevaluated industrial township of India.

Evaluation of the fungal activity of Beauveria bassiana, Metarhizium anisopliae and Paecilomyces lilacinus as biocontrol agents against root-knot nematode, Meloidogyne incognita on cowpea

BackgroundIn the current years, nematotoxic or antagonistic compounds for example, toxins, enzymes, or compounds derived from the metabolites of fungal culture filtrates have greatly increased.ObjectiveThis research was designed to evaluate two fungi, Beauveria bassiana and Metarhizium anisopliae, commonly used only as bio-insecticides in Egypt for their nematicidal potential compared to Paecilomyces lilacinus, one of the most important fungi parasitizing on eggs of root-knot nematode, Meloidogyne incognita.ResultsThe tested fungi either as filtrate or spore affected egg hatching and survival of second stage juveniles at different degrees according to fungal filtrate dilution and spore concentration and exposure period under in vitro study. Under screen house conditions, the tested fungi as filtrates or spores were used to control root-knot nematode on cowpea. The overtopped significant results were gained with P. lilacinus filtrate at standard dilution and recorded the highest mean overall percentages nematode reduction (84.5%). The second rank was obtained by B. bassiana culture filtrate, where it significantly reduced all nematode numbers with a mean of 81.1% at standard dilution. M. anisopliae caused 78.5% as a mean percentages nematode reduction followed by other dilutions and untreated check. When using spore concentrations, the overtopped significant results were gained with P. lilacinus at the highest spore concentration (1 × 108) and recorded the highest mean percentages nematode reduction (85.3%). The second rank was obtained by M. anisopliae, where it reduced all nematode numbers as an average of 83.6%. B. bassiana caused 77.1% as a mean percentages nematode reduction at the highest spore concentration. At all cases, all treatments significantly promoted plant growth and yield criteria and these increases were positively proportional to the filtrate dilution or spore concentration higher than the untreated plants.ConclusionsIt can be concluded that B. bassiana, M. Anisopliae, and P. lilacinus as antagonistic fungi proved to be efficient against root-knot nematode, incognita infecting cowpea as they reduced nematode criteria which subsequently improved plant growth and yield of cowpea.

Airborne fungal spore concentration in some selected indoor and outdoor sites: Threats of respiratory problems

Airborne fungal spore concentration in some selected indoor and outdoor sites: Threats of respiratory problems

The fluctuations of airborne fungal components in western Romania

Outdoor regional concentrations of airborne fungal spores and fungal fragments were measured using the 7-day Lanzoni sampler. The daily and intradiurnal fluctuations recorded during the monitored period have been studied. The multiple regression analysis was performed in order to determine how much of the total variance in these concentrations could be explained by meteorological parameters. Daytime periodicity statistically significant was established only in a few cases. As the relative importance of the weather factors varied, they could not be ranked according to their effect.

Fungal bio-aerosol in multiple micro-environments from eastern India: source, distribution, and health hazards

Health hazards associated with bio-aerosol is gaining immense importance in recent time. However, studies linking the probable source characterization of bio-aerosol, and their potential effect as respiratory ailments on the local people are extremely rare over the Indian subcontinent as well as in global perspective. To fill our knowledge gap, we have conducted a 3-year study on fungal bio-aerosol characterization, possible source segregation, identification of health hazardous fungal species and their role in causing allergy from seven different micro-environments over a semi-rural site of lower Indo-Gangetic Plain, West Bengal, India. The result showed the highest fungal spore concentration as well as spore diversity in the crop field (4477 ± 1343 spores m−3) and the lowest in the classroom (1994 ± 651 spores m−3). Ascospore, basidiospore, Cladosporium, and Aspergilli group were the primary indoor spores. The marker species for the crop field were Curvularia and Drechslera, whereas Ganoderma was for the factory environment. Source profile of the fungal spore of different micro-environments indicates the domination of outdoor species, whereas enclosed micro-environments have been dominated with spores of indoor origin. Aspergillus, Curvularia, Penicillium, and Rhizopus oryzae showed maximum correlation with the local allergic rhinitis and asthmatic patients. In skin prick test, Aspergillus sp., contributing a maximum percentage of the total culturable fungi, was found to be an expected potent allergic candidate in both non-asthmatic and asthmatic patients, as well. This study will directly help the inhabitants to avoid the hazardous fungal sensitization in different micro-environments.

Height and hourly variations in the concentration of airborne pollen grains and fungal spores in Sosnowiec (Poland)

The aim of the work was to compare the qualitative and quantitative composition of aeroplankton in Sosnowiec (Poland) at three heights. The research was conducted on July 3rd, 4th and 5th, 2018 with the help of three Burkard spore traps: one stationary and two portable ones. The analyses were carried out at an altitude of 83 m, 15 m and at the ground level. Aerobiological data was recorded every hour and the collected pollen grains and fungal spores were determined later on. The relationships between individual meteorological conditions and different features of the alder pollen season were determined using Spearman’s rank correlation coefficients. The research has shown that the greatest fluctuations in the daily pollen count occurred at the lowest measuring point, i.e. at the ground level. The largest part of the determined palynomorphs were fungal spores, the most numerous of which was Cladosporium, followed by Alternaria, Epicoccum and Botrytis. Statistical analysis showed that the highest concentrations of fungal spores and plant pollen grains were influenced by wind speed, maximum gust of wind and solar radiation.

Fungal Diseases in Two North-West Spain Vineyards: Relationship with Meteorological Conditions and Predictive Aerobiological Model

Grey mould, powdery mildew, and downy mildew are the most frequent fungal diseases among vineyards worldwide. In the present study, we analysed the influence of the fungi causing these diseases (Botrytis, Erysiphe, and Plasmopara, respectively) on two viticulture areas from North-western (NW) Spain during three growth seasons (2016, 2017, and 2018). The obtained results showed the predominant concentration of the Botrytis airborne spores, mainly from the beginning of the Inflorescence emerge phenological stage (S-5) until the end of the Flowering phenological stage (S-6). Erysiphe and Plasmopara airborne spore peak concentrations were more localised around Flowering (S-6) and Development of fruits (S-7) phenological stages. We applied a Spearman’s correlation test and a Principal Component Analysis to determine the influence of the meteorological parameters on the concentration of airborne spores. Taking into account the variables with the highest correlation coefficient, we developed multiple regression models to forecast the phytopathogenic fungal spore concentrations. The Botrytis model regression equation explained between 59.4–70.9% of spore concentration variability. The Erysiphe equation explained between 57.6–61% and the Plasmopara explained between 39.9–55.8%. In general, we found better prediction results for mean daily concentrations than sporadic spore peaks.

Artificial neural models of concentrations of fungal spores in the airfor aerobiological research

This article describes in detail an advanced statistical method, the artificial neural network, and the possibilities for its application in aerobiological analyses. The study and models involve the concentration of fungal spores in the air and their relationship with various biological and environmental factors. The author hopes that this work will contribute to a wider use of this method not only in the study of spores but also the concentration of pollen grains.

Development of fungal spore staining methods for flow cytometric quantification and their application in chlorine-based disinfection.

Fungal contamination in drinking water has been becoming a hot topic. The routine enumeration method of fungal spores is heterotrophic plate counts (HPC). However, this method is time-consuming and labor-intensive and there is also the difficulty of enumerating viable but non-culturable cells. In this study, a rapid, simple and accurate method for quantifying fungal spores and discriminating their viability in water was established using flow cytometry (FCM) combined with fluorescence dyes. The optimal staining conditions are as follows: spores suspensions are sonicated at 495W for 5min as pretreatment, and then 10μL of SYBR Green I (100×) and 30mM Ethylene diamine tetraacetic acid are added to a 500μL water sample, which incubate at 35°C for 20min in dark. The concentration of fungal spores measured by FCM was highly correlated with HPC results and microscope observations, with correlation coefficient of 0.996 and 0.988, respectively. This staining method can be widely applied to the enumeration and viability evaluation of fungal spores. In addition, chlorine-based inactivation of three genera of fungal spores was assessed by plating and FCM. The result showed that all three genera of fungal spores lost culturability firstly and then membrane integrity decreased, preliminarily revealing the inactivation mechanism. The inactivation rate constants of membrane damage varied in the following order: chlorine dioxide>chlorine>chloramine. This study concluded that FCM is an appropriate and alternative tool to detect fungal spores' viability and can be used for evaluating the fungal inactivation by disinfectants.

Intradiurnal variation of predominant airborne fungal spore biopollutants in the Central European urban environment.

Fungal spores are an important cause of allergic respiratory diseases worldwide. However, little is known about the intradiurnal pattern of spore concentrations of different fungal spore types in the air of the urban area. In this study, we evaluated bihourly variation in spore concentration of eight predominant fungal spore types in the atmosphere of Bratislava city (Agrocybe, Alternaria, Cladosporium, Coprinus, Exosporium, Epicoccum, Ganoderma, Leptosphaeria) with the aim to understand the relationships between the spore concentrations against associated environmental variables. Spore samples were collected using a Hirst-type volumetric aerospore trap from January to December 2016. Alternaria, Cladosporium, Epicoccum and Exosporium peaked during the daytime period between 10:00 and 16:00, while for Agrocybe, Ganoderma, Coprinus and Leptosphaeria, the nighttime peaks (20:00 and 04:00) were observed. Effect of a complex of environmental variables on bihourly concentrations of selected airborne fungal spore taxa was evaluated through multiple regression analysis. Air temperature, wind speed, sunshine duration and precipitation were positively associated with daytime spore types, while the association with nighttime spores was negative. In contrast, relative air humidity influenced negatively Exosporium daytime spore type but positively the Leptosphaeria nighttime spore type. Moreover, a circadian cycle of light and darkness was considered as an important predictor of nighttime spore levels. Among the atmospheric pollutants, PM10 was positively associated with all analysed daytime spores, while except for Leptosphaeria, O3 was negatively associated with nighttime spore types. NO2 and PM10 had mixed effects on nighttime spore levels. In general, air temperature, PM10 and wind speed were environmental parameters with great influence on airborne fungal spore concentration, being present in eight, seven and four regression models, respectively. Constructed regression models which the best explained variation in fungal spore concentrations were those for Ganoderma (R2 = 0.38) and Alternaria (R2 = 0.31).

Assessment of Airborne Fungal Spores in a tertiary care hospital in South Western Nigeria

TPS 752: Respiratory effects and allergies, Exhibition Hall, Ground floor, August 27, 2019, 3:00 PM - 4:30 PM Background/Aim: Increasing evidences show that exposure to indoor fungal spores has resulted in increased prevalence of hospital-acquired infections. This study aimed to determine the burden of airborne fungi species in the indoor environments of a tertiary hospital in South Western Nigeria. Methods: Air samples were collected in the dry (January–April) and raining (June-September) seasons from four categories of wards viz; surgery (8 wards), obstetrics/gynecology (5 wards), medical (8 wards) and paediatric (6 wards). Air samples were collected using a two-stage Anderson sampler at a flow rate of 15L/min for 15 minutes in the morning (8:00-11:00) and evening (13:00-16:00) hours over a 3-day period. A total of 966 air samples were cultured each on Potato-dextrose agar (PDA) and Sabouraud-dextrose agar (SDA) and incubated at 25°C for 7-10 days. Total fungi count (TFC) was presented in colony-forming unit per cubic meter (CFU/m3) and compared to recommended concentration of fungal spores in hospital air (≤ 25CFU/m3). Analysis was performed using t-test and ANAOVA at p<0.05. Results: Majority, 930 (96.3%) and 934 (96.7%) of the samples were positive for fungi on PDA and SDA respectively. In both seasons, the paediatric wards recorded the highest mean TFC on PDA (dry:38.33 ± 30.41CFU/m3; raining:44.78 ± 40.16CFU/m3,p<0.05) and SDA (dry:48.22 ± 33.17CFU/m3; raining:52.00 ± 36.76CFU/m3) while the surgery wards had the least TFC on PDA (dry:28.40 ± 21.37 CFU/m3; raining:32.77 ± 29.95CFU/m3) and SDA (dry:42.70 ± 19.44 CFU/m3; raining:39.44 ± 29.61CFU/m3). The mean TFC in each ward was above the recommended concentration of 25CFU/m3. The most frequent occurring fungal species was Aspergillus spp. constituting about 30.5% of the total isolates. Conclusions: This study revealed high fungal contamination in the wards. The presence of Aspergillus spp. pose great threat to immunocompromised patients. Therefore, periodic survey and efficient ventilation system are necessary to prevent possible hospital-acquired infections.

Quantitative evaluation of bioaerosols in different particle size fractions in dust collected on the International Space Station (ISS).

Exposure to bioaerosols can adversely influence human health through respiratory tract, eye, and skin irritation. Bioaerosol composition is unique on the International Space Station (ISS), where the size distribution of particles in the air differs from those on Earth. This is due to the lack of gravitational settling and sources of biological particles. However, we do not understand how microbes are influenced by particle size in this environment. We analyzed two types of samples from the ISS: (1) vacuum bag debris which had been sieved into five different size fractions and (2) passively collected particles on a tape substrate with a passive aerosol sampler. Using quantitative polymerase chain reaction (qPCR), the highest concentration of fungal spores was found in the 106-150 μm-sized sieved dust particles, while the highest concentration of bacterial cells was found in the 150-250 μm-sized sieved dust particles. Illumina MiSeq DNA sequencing revealed that particle size was associated with bacterial and fungal communities and statistically significant (p = 0.035, p = 0.036 respectively). Similar fungal and bacterial species were found within the passive aerosol sample and the sieved dust samples. The most abundant fungal species identified in the aerosol and sieved samples are commonly found in food and plant material. Abundant bacterial species were most associated with the oral microbiome and human upper respiratory tract. One limitation to this study was the suboptimal storage conditions of the sieved samples prior to analysis. Overall, our results indicate that microbial exposure in space may depend on particle size. This has implications for ventilation and filtration system design for future space vehicles and habitats.

Logistic regression models for predicting daily airborne Alternaria and Cladosporium concentration levels in Catalonia (NE Spain).

Alternaria and Cladosporium are the most common airborne fungal spores responsible for health problems, as well as for crop pathologies. The study of their behavior in the air is a necessary step for establishing control and prevention measures. The aim of this paper is to develop a logistic regression model for predicting the daily concentrations of airborne Alternaria and Cladosporium fungal spores from meteorological variables. To perform the logistic regression analysis, the concentration levels are binarized using concentration thresholds. The fungal spore data have been obtained at eight aerobiological monitoring stations of the Aerobiological Network of Catalonia (NE Spain). The meteorological data used were the maximum and minimum daily temperatures and daily rainfall provided by the meteorological services. The relationship between the meteorological variables and the fungal spore levels has been modeled by means of logistic regression equations, using data from the period 1995-2012. Values from years 2013-2014 were used for validation. In the case of Alternaria, three equations for predicting the presence and the exceedance of the thresholds 10 and 30 spores/m3 have been established. For Cladosporium, four equations for the thresholds 200, 500, 1000, and 1500 spores/m3 have been established. The temperature and cumulative rainfall in the last 3days showed a positive correlation with airborne fungal spore levels, while the rain on the same day had a negative correlation. Sensitivity and specificity were calculated to measure the predictive power of the model, showing a reasonable percentage of correct predictions (ranging from 48 to 99%). The simple equations proposed allow us to forecast the levels of fungal spores that will be in the air the next day, using only the maximum and minimum temperatures and rainfall values provided by weather forecasting services.