Biomonitoring Of Allergenic Pollen In Western Romania And Relationships With Meteorological Variables

BIOMONITORING OF ALLERGENIC POLLEN IN WESTERN ROMANIA AND RELATIONSHIPS WITH METEOROLOGICAL VARIABLES

Nicoleta IANOVICI

1Department of Biology and Chemistry, University of Timisoara, Romania

Corresponding author e-mail: [anonimizat]

Received 5 November 2015; accepted 2015

ABSTRACT

The analysis of the airborne pollen content concerned 20 taxa, whose pollen has allergenic properties and occurs in large quantities in the air of Timisoara: Alnus, Corylus, Populus, Betula, Poaceae, Rumex, Plantago, Urtica,Chenopodiaceae and Artemisia. Analysis of the pollen count in Timisoara was performed on the basis of the data collected in the year 2009. Ambrosia, Urticaceae and Poaceae reached the highest airborne pollen concentrations in Timisoara. The relationships between allergenic pollen concentration and environmental factors were assessed using multiple linear regressions.

KEY WORDS: phenology, biomonitoring

INTRODUCTION

The environmental sensitivity of many plant life cycles reflects different life-history strategies in natural and agricultural areas (Wilczek et al, 2010). Plant phenology models are important tools in a wide range of issues such as agricultural practices, forestry and aerobiology. Phenology is a major bio-indicator of climate change impact on ecosystems and helpful in prediction of the impact of global warming (Schleip et al, 2006). Plant phenology include reproductive events such as flowering, fruiting, seed dispersal and germination. Flowering phenology is a critical stage of development that strongly influences reproductive success of plants (Faur et al, 2003a). The timing, duration and intensity of flowering may be affected by some biotic factors. Several climatic parameters such as temperature, precipitation, irradiance, soil nutrient concentration and other variables can trigger flowering in different taxa (Bustamante & Búrquez, 2008; Forrest & Miller-Rushing, 2010). As many authors have observed, the aerobiological processes (emission, dispersion, transport, deposition of pollen grains) are affected by the meteorological variables (Cecchi et al, 2010).

In Romania, at the Department of Biology of the West University of Timisoara, continuous pollen biomonitoring has been carried out since 1999. This type of work was started by Faur & Ianovici (2001). The results of the studies were published in numerous papers (Juhasz et al, 2001; Radišič et al, 2003; Faur et al, 2003b; Juhasz et al, 2004; Radisič et al, 2004; Juhasz et al, 2005; Ianovici, 2008a; Ianovici, 2008b; Ianovici et al, 2013a; Ianovici, 2014). The pollen spectrum show the distribution of frequently occurring taxa, particularly those having allergenic importance (Ianovici & Sîrbu, 2007; Ianovici, 2007c; Ianovici, 2008c). Airborne pollen content at Timisoara led us to identify the flowering plants that correspond to the three seasons corresponding to spring (12–23 weeks), summer (24–37weeks) and autumn (37–49weeks) (Ianovici, 2007b). The population with pollen allergy increases every year. An extremely high increase of patients allergic to Ambrosia was observed in the western part of Romania (Ianovici et al, 2009; Panaitescu et al, 2013; Ianovici et al, 2013b; Panaitescu et al, 2014; Leru et al, 2015). The symptoms of pollen allergy confirm a good correlation with the airborne pollen count (Obtułowicz et al, 1991; Florido et al, 1999; Ianovici, 2007a; Rodríguez et al, 2011; Ščevková et al, 2015].

The aim of the study was to analyse the pollen counts of selected allergenic taxa (20) in the air of Timisoara City (western Romania). Using data from 2009, the effect of climatic variables on pollen concentrations was examined with multiple regression analysis. The analysis was useful to detect which of the climatic variables had the strongest impact on onset and duration.

MATERIALS AND METHODS

Timisoara and its surroundings is located at an altitude of 86 m above sea level and characterized by arable lands and mixed forests. Many woody taxa are distributed in parks, alongside roads and cemeteries. The urban flora includes several plants used for ornamental purposes: Taxaceae/Cupressaceae and Pinaceae (Ianovici, 2007d; Ianovici, 2009). Herbaceous taxa occurs spontaneously in open areas, or it is cultivated in parks and private gardens (Ianovici, 2007e). Ambrosia artemisifolia and Artemisia vulgaris are cited as the more important species of the Timisoara City and are relatively common, especially bordering avenues and roads and could be considered the most relevant pollen sources for these types (Ianovici et al, 2013b).

Airborne pollen was monitored throughout the year. Airborne pollen were monitored using Lanzoni pollen trap. The sampling airflow rate was 10 l/min. Pollen was caught on a 24 mm wide transparent tape coated by a thin film of silicon oil. The tape was mounted on a cylinder rotating at a speed of 2 mm per hour. A complete rotation of the cylinder took seven days. Weekly tape strips were cut into 7 pieces, each 48 mm in length. Each piece corresponded to one day sampling. They were then mounted and stained in glycerine jelly mixed with basic fuchsine. Identification of the pollen was done by light microscopy, at a magnification of x 400. Pollen concentration was expressed as the daily average of pollen grains per cubic meter of air. A small fraction, of airborne pollen flora remained unidentified. Due to the difficulty on distinguishing some pollen of species belonging to the same family, because of its similar morphology, it is common to aggregate them by the family names (Sousa et al, 2010).

All statistical tests were performed using the software package SPPS. The multiple regression analysis was performed in order to determine how much of total variance in pollen counts can be explained by meteorological variables. A total of nine meteorological factors were selected for this investigation (table 1).

Table 1. The meteorological variables according to months (2009)

RESULTS AND DISCUSSIONS

A total of 23 pollen taxa, of these 16 taxa arboreal and 7 non-arboreal, were identified during 2009. The number of pollens in the atmosphere from herbaceous taxa was highest during summer (June to October) whereas pollens from woody taxa dominated during spring (February to May). Types representing arboreal pollen were reached the highest values during April. A maximum concentration of non-arboreal taxa was recorded in August. The richness of the pollen types varied throughout the year. The maximum number of pollen types was registered in April (18 types).

The twenty pollen taxa were then subjected to analyses. The pollen of these plants also cause the majority of pollinosis in Europe. Multiple regression analysis was performed in order to identify the major variables likely to influence the dynamic of the airpollen. Multiple linear regression is a commonly used method in environmental sciences. The aim was not to develop predictive model, but rather to give information on types of factors that might be controlling dispersion of each pollen species. Tables 4 show the statistically multiple linear regressions for airpollen. Only the highest values of the statistically significant correlation coefficients were selected.

Table 2 summarizes the descriptive statistics and analysis results. For Urticaceae, meteorological parameters explained 43.25% of the total variance. The most important agents influencing the Urticaceae pollen count (in multiple regression) are atmospheric pressure, daily average relative humidity, near-surface soil temperature, sunshine hours and daily average wind speed. Among the meteorological parameters analysed, daily average relative humidity was the one that most influenced the pollen airborne concentrations. Mean daily average temperature and near-surface soil temperature also showed to have some influence on the pollen dispersion. Pollen concentrations of species examined showed significant associations with mean daily average temperature (Populus, Juglans, Pinaceae, Poaceae, Ambrosia, Plantago), daily average relative humidity (Corylus, Taxaceae/Cupressaceae, Betula, Carpinus, Salix, Ulmus, Fraxinus, Populus, Juglans, Quercus, Pinaceae, Poaceae, Urticaceae, Plantago), near-surface soil temperature (Alnus, Corylus, Salix, Ulmus, Fraxinus, Populus, Poaceae, Urticaceae, Plantago), sunshine hours (Tilia, Urticaceae), nebulosity (Carpinus, Pinaceae), atmospheric pressure (Taxaceae/Cupressaceae, Ulmus, Urticaceae), daily average wind speed (Betula, Carpinus, Ulmus, Fraxinus, Urticaceae), daily maximum wind speed (Alnus, Carpinus, Ulmus, Fraxinus) and quantities of precipitations (Tilia). Average wind speeds were found to be more important than maximum wind speeds. Amounts of rain were not found to be significant. The best associations were found between daily values of concentration and temperature. Artemisia, Rumex and Chenopodiaceae/Amaranthaceae were found not to be associated with weather variables.

In multiple regression analysis, significant associations between the pollen counts and daily average relative humidity, mean daily average temperature and near-surface soil temperature were noted. The multiple regression showed strong associations with daily average relative humidity for 14 taxa, while for 9 taxa a association was noted with the near-surface soil temperature. The other values here are the regression coefficients. More interesting for our understanding and interpretation are the unstandardized coefficients (B).These indicates that for every unit increase in explanatory variables (apart from daily max. wind speed), the model predicts a decrease in pollen concentrations for Alnus, Corylus, Taxaceae/Cupressaceae, Betula, Carpinus, Salix, Ulmus, Fraxinus, Populus, Juglans, Quercus. For the pollen types who appear in the summer season-early fall season (Pinaceae, Tilia, Poaceae, Ambrosia, Urticaceae, Plantago), significant effects of the variables are mostly positive (increasing concentrations). The results indicate that mean daily average temperature is a powerful predictor of Ambrosia pollen. Daily average wind speed make a significant contribution to the explanation of variance in Urticaceae pollen concentrations. It has been observed that there is not a clear relationship between the amount of pollen collected in the air and the meteorological variables. Taking into account regression results, the fluctuations of concentrations pollen types were better explained in some cases (Urticaceae, Fraxinus, Ulmus, Poaceae).

Fig.1. Alnus type Fig.2. Corylus type

Fig.3. Carpinus type Fig.4. Betula type

Fig.5. Taxaceae/Cupressaceae type Fig.6. Ulmus type

Fig.7. Fraxinus type Fig.8. Populus type

Fig.9. Salix type Fig.10. Quercus type

Fig.11. Pinaceae type Fig.12. Juglans type

Fig.13. Tilia type Fig.14. Chenopodiaceae/Amaranthaceae type

Fig.15. Urticaceae type Fig.16. Plantago type

Fig.17. Rumex type Fig.18. Poaceae type

Fig.19. Artemisia type Fig.20. Ambrosia type

Fig. 3. Pollen richness (R) as number of pollen types

Fig.4.

.

Looking at the p-value of the t-test for each predictor, we can see that each weather variables contributes to the model, but not equally and not to the same pollen types.

The seasonal cycle of plants is influenced to the greatest extent by temperature, photoperiod and precipitation. Timing developmental occurrence to coincide with favourable seasonal conditions is critical for plant growth, survival and reproduction. Responses of plant involve cellular, metabolic, morphological or developmental changes that require time to complete (Wilczek et al, 2010).

Water availability may determine the duration of the growing season and thus can have important effects on the relationship between phenology and fitness (Franks et al. 2007).

Plants make use of several cues that serve as reliable indicators of season and thus resource availability, of which light and temperature are usually most important in temperate plant species (Wilczek et al, 2010). In particular spring development in the mid latitudes depends especially on temperature in winter and spring. In temperate environments, optimum ambient temperatures for growth are rarely exceeded (Schaber & Badeck, 2002). Growth and development rates typically increase with ambient temperatures up to some optimum or maximum, and then decline as warming continues. Ambient temperature is a seasonal cue that cycles annually in temperate climates following patterns of day length and insolation (Wilczek et al, 2010). Regression analysis showed that rainfall and maximum temperature were the most important variables in Mediterranean areas, while both maximum and minimum temperatures prior to flowering were the most weighty meteorological parameters in Eurosiberian areas (García-Mozo et al, 2006).

Light quantity contributes to plant growth and development, but day length can also serve as an important developmental cue. Increasing day duration indicates the arrival of spring. Declining photoperiods are a reliable indicator of the end of the growing season (Bohlenius et al, 2006; Savolainen et al, 2007). Day length can also serve as an powerful indication for the appropriate timing of flowering and fruiting with respect to seasonal patterns of temperature and precipitation (Wilczek et al, 2010). Timisoara presents a pollen spectrum similar to those of nearby localities, in which many pollen types are represented, the long tails indicating long flowering periods. According to the literature and aerobiological and ecological data (Bartkovă-Ščevkowă, 2003; Laaidi et al, 2003; Makra et al, 2004; Peternel et al, 2005), temperature and average relative humidity are the environmental factors which most strongly affects the generative and vegetative development and the occurrence of pollen in air (Kasprzyk, 2008). The resulting regression analysis is only an approximate indication of which variables are useful for predicting pollen counts (Makra et al, 2004).

Identifying, quantifying and biomonitoring of allergenic pollen may contribute to: targeting specific preventive measures, assessing the role played by the allergens in sensitization, directing immediate and future therapeutic plans, directing production of allergenic extracts and vaccines according to the presence of allergophytes in a certain area, producing plant pollen calendars which show the dynamics of pollen and anemophilous plants, the management of parks and green areas.

CONCLUSIONS

The objective of this study was to examine the relationships between environmental factors and pollen concentrations. Some pollen types recorded during this study could be involved in allergenic pollinosis. This is a preliminary study and effects of meteorological variables on pollen counts could not be clearly identified with the evaluation of one-year data yet.

REFERENCES

Bustamante E., Burquez A. 2008. Effects of Plant Size and Weather on the Flowering Phenology of the Organ Pipe Cactus (Stenocereus thurberi). Annals of Botany. 102: 1019–1030.

Faur A, Ianovici N. 2001. Biologic pollution with grasses’s in the South-West of Romania, Annals of West University, ser. Biology, 3-4: 1-6.

Faur A., Ianovici N., Sinitean A. 2003a. Phenoecology studies on some anemophile ligneous Magnoliatae from Timișoara, Annals of West University of Timișoara, ser. Biology, 5-6: 17-24.

Faur A., Ianovici N., Sinitean A. 2003b. Airbiological study on the Hamamelidae (Amentiferae) pollen in the West Plain, Annals of West University of Timișoara, ser. Biology, 5-6: 1-10.

Florido JF, Delgado PG, de San Pedro BS, Quiralte J, de Saavedra JM, Peralta V, Valenzuela LR. 1999. High levels of Olea europaea pollen and relation with clinical findings. Int Arch Allergy Immunol. 119 (2):133-137.

Forrest J., Miller-Rushing A.J. 2010. Introduction. Toward a synthetic understanding of the role of phenology in ecology and evolution. Phil. Trans. R. Soc. B. 365, 3101–3112.

Ianovici N. 2007a. Airborne Rumex pollen in the atmosphere of Timișoara, Romania, Annals of West University of Timisoara, Series of Chemistry, 16 (4): 133-140.

Ianovici N. 2007b. Quantitative aeropalinology in the atmosphere of Timisoara City, Romania,  Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, Agriculture, 63: 417-423.

Ianovici N. 2007c. Calendarul polenului aeropurtat pentru Timișoara, România, Lucrări Științifice. Seria Agronomie, 50 (2): 337-342.

Ianovici N. 2007d. Aerobiological monitoring of Pinaceae pollen in Timisoara over five years, Annals of West University of Timisoara, Series of Chemistry, 16 (4): 125-132.

Ianovici N. 2007e. The principal airborne and allergenic pollen species in Timișoara, Annals of West University of Timișoara, ser. Biology, 10: 11-26.

Ianovici N. 2008a. Urticaceae pollen concentration in the atmosphere of western Romania, Lucrări științifice, Seria Horticultură, 51: 125-130

Ianovici N. 2008b. Airborne Poaceae pollen in urban environment for 2000-2004, Analele Universitatii din Craiova – Agricultură, Montanologie, Cadastru, XXXVIII(B): 224-230.

Ianovici N. 2008c. The analysis of daily concentrations of airborne pollen in the West and Southwest of Romania, Scientific Annals of ‘‘Alexandru Ioan Cuza’’ University of Iasi. (New Series), Section 2. Vegetal Biology, LIV (2), 73-78.

Ianovici N. 2009. Aerobiological monitoring of Taxaceae/Cupressaceae pollen in Timisoara, Journal of Horticulture, Forestry and Biotechnology, 13: 163-170.

Ianovici N. 2014. 15 years of research on invasive and allergenic plant: Ambrosia artemisiifolia. International Conference "Practice and Experience in Environmental Protection" Ecomediu, 12th edition, Arad, pp.85-88.

Ianovici N., Birsan M.V., Tudorică D., Balița A. 2013a. Fagales pollen in the atmosphere of Timișoara, Romania (2000-2007), Annals of West University of Timișoara, ser. Biology, 16 (2), 115-134

Ianovici N., Bunu C., Marusiac L. 2009. Ambrosia artemisiifolia in Romania, Journal of Romanian Society of Alergollogy and Clinical Immunology, 6 (4): 146.

Ianovici N., Panaitescu Bunu C., Brudiu I. 2013b. Analysis of airborne allergenic pollen spectrum for 2009 in Timișoara, Romania, Aerobiologia, 29 (1): 95-111.

Ianovici N., Sîrbu C. 2007. Analysis of airborne ragweed (Ambrosia artemisiifolia L.) pollen in Timișoara, 2004, Analele Universității din Oradea, Fascicula Biologie, XIV: 101-108.

Juhász I. E., Juhász M., Radišič P., Ianovici Nicoleta, Sikoparija B. 2005. Aerobiological Importance of Grasses in the DKMT Euroregion, The 12th Symposium On Analytical And Environmental Problems, 26 September 2005, Szeged, 144-148.

Juhasz M., Juhasz I.E., Gallovich E., Radisič P., Ianovici N., Peternel R., Kofol-Seliger A. 2004. Last year`s ragweed pollen concentrations in the southern part of the Carpathian Basin, The 11th Symposium on Analitical and Environmental problems, Szeged, 24 September 2004, 339-343.

Juhász M., Oravecz A., Radisic P., Ianovici N., Juhász I.E. 2001. Ragweed pollen pollution of Danube-Cris-Mures-Tisza Euroregion (DCMTE) – Proceeding of the 8th Symposium on Analytical and Environmental Problems, Szeged (Hungary), 210-215.

Leru P.M., Matei D., Ianovici N. 2015. Health impact of Ambrosia artemisiifolia reflected by allergists practice in Romania. A questionnaire – based survey, Annals of West University of Timișoara, ser. Biology, 18 (1), 43-54.

Obtułowicz K., Szczepanek K., Radwan J., Grzywacz M., Adamus K., Szczeklik A. 1991. Correlation between airborne pollen incidence, skin prick tests and serum immunoglobulins in allergic people in Cracowm, Poland, Grana, 30:1, 136-141.

Panaitescu Bunu C., Ianovici N.., Marusciac L., Cernescu L., Matis B., Muresan R., Balaceanu A. 2013. Impact of senzitization to Ambrosia pollen and to other inhaled allergens in the population of the Timisoara area, Journal of Romanian Society of Alergollogy and Clinical Immunology, 10 (2): 76-77.

Panaitescu C., Ianovici N., Marusciac L., Cernescu LD, Tamas PT, Lazarovicz RA. 2014. Sensitisation to Ambrosia pollen and other airborne allergens in the population of the Western region of Romania, ALLERGY. 69, 434.

Radišič P., Sikoparija B., Juhász M., Ianovici N. 2003. Betula pollen season in the Danube – Kris – Mures – Tisa Euroregion (2000-2002), Annals of Faculty Engineering Hunedoara – Journal of Engineering, I (2), 197-200.

Radisič P., Sikoparija B., Juhasz M., Ianovici N. 2004. Corylus airborne pollen in Danube-Kris-Mures-Tisa Euroregion, Central European Journal of Occupational and Environmental Medicine, 10 (1), 35-40.

Rodríguez D, Dávila I., Sánchez E., Barber D., Lorente F., Sánchez J. 2011. Relationship Between Airborne Pollen Counts and the Results Obtained Using 2 Diagnostic Methods: Allergen-Specific Immunoglobulin E Concentrations and Skin Prick Tests. J Investig Allergol Clin Immunol. 21(3): 222-228.

Ščevková J, Dušička J, Hrubiško M, Mičieta K. 2015. Influence of airborne pollen counts and length of pollen season length of selected allergenic plants on the concentration of sIgE antibodies on the population of Bratislava, Slovakia. Ann Agric Environ Med. 22(3): 451–455.

Schleip C., Menzel A., Estrella N., Dose V. 2006. The use of Bayesian analysis to detect recent changes in phenological events throughout the year. Agricultural and Forest Meteorology 141, (2-4): 179-191.

Wilczek A. M., Burghardt L. T., Cobb A. R., Cooper M. D., Welch S. M., Schmitt J. 2010. Genetic and physiological bases for phenological responses to current and predicted climates. Phil. Trans. R. Soc. B. 365, 3129–3147.

Sousa S. I. V., Martins F.G., Pereira M. C., Alvim-Ferraz M. C. M., Ribeiro H., Oliveira M., Abreu I. 2010. Use of Multiple Linear Regressions to Evaluate the Influence of O3 and PM10 on Biological Pollutants. Int. J. Civil Eng. Environ. Eng.2: 107–112.

Bio-monitoring results showed that a total of 20 allergenic pollen types were located in the air of the study area. Qualitative and quantitative analyses carried out using standard protocol in association with the comparison of reference slides and consulting the published literatures.

Many of the pollen grains found in the sampler were allergenic.

When observing the daily variations in pollen concentration in the air, there is a clear negative relationship with precipitation, as rain washes the pollen out of the atmosphere.